definition of pre assignment

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Meaning of pre-assigned in English

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• It was unclear whether the bomber dropped its payload on its pre-assigned target .
• Each session had pre-assigned discussion topics , making it very unlikely that a debate would develop .
• Each client workstation copies the backup data to a preassigned location .
• accommodate
• accommodate someone with something
• administration
• arm someone with something
• hand something around
• hand something back
• hand something down
• hand something in
• re-equipment
• reassignment

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any of the rods that join the edge of a wheel to its centre, so giving the wheel its strength

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Where Assessment Comes First

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Pre-assessment: Where Teaching and Learning Begins

What is Pre-assessment? Pre-assessment is an action or strategy at the start of instruction that displays student’s incoming knowledge and skills and in turn informs teaching and learning. It can occur at the start of a lesson, the beginning of a unit, or the introduction of a new idea, concept or skill.

Why Should I Use It? Much of the emerging research on effective teaching and assessing confirms the value of starting where the students are in their sequence and cycle of learning as this is most likely to increase their success. John Hattie, in his research on Visible Learning, found that formative assessment has an effect size of .9, nearly at the top of the list. http://visible-learning.org/hattie-ranking-influences-effect-sizes-learning-achievement/

How Can I Use It? Pre-assessment is used to identify incoming knowledge, recognize misconceptions about a topic, raise student’s curiosity, and immediately engage them in new learning. It informs planning and guides next steps for the teacher and the learner. This may relate to complexity of content, alignment of instructional processes, resources, pacing, and grouping. If it makes sense to use a GPS when traveling then it also makes sense to use a pre-assessment when teaching to ensure everyone is on the right pathway to success.

Strategies Without Technology Corners: Select a position and provide an annotated defense based on prior learning. Entrance Slip: Students map what they know about a topic, respond to questions, or record their ideas. Predictions: Students predict the content and purpose of upcoming learning.

Strategies With Technology Padlet  can be used for brainstorming or displaying incoming knowledge. Lino is a type of electronic sticky note where students can post and sort their responses by category. Google Forms can create quick quizzes that provide data on each student’s knowledge. Plickers lets you poll your class as each student holds up a card displaying their answer. Cards can be scanned with your phone producing a class graph or individual student report.

Coming up in next:  Strategies for a purpose Followed by: Responding to the data

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Definition of 'preassign'

Preassign in british english.

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Pre-Assignment Period definition

Related to pre-assignment period.

Assignment Date means _____________________, 199___.

Lender Assignment Agreement means an assignment agreement substantially in the form of Exhibit D hereto.

Collateral Assignment Agreement has the meaning set forth in Section 9.05.

Assignment Amount with respect to a Bank Investor shall mean at any time an amount equal to the lesser of (i) such Bank Investor's Pro Rata Share of the Net Investment at such time and (ii) such Bank Investor's unused Commitment.

term assignment means, in relation to an employee, i. a term assignment within the meaning of the local collective agreement, or ii. where no such definition exists, a term assignment will be defined as twelve (12) days of continuous employment in one assignment

Qualified assignment agreement means an agreement providing for a qualified assignment within the meaning of section 130 of the United States Internal Revenue Code, United States Code Title 26, as amended from time to time;

prospective assignment means an assignment that is intended to be made in the future, upon the occurrence of a stated event, whether or not the occurrence of the event is certain;

Lease Assignment has the meaning set forth in Section 3.5(d).

Loan Assignment has the meaning set forth in the Purchase and Sale Agreement.

IP Assignment Agreement has the meaning set forth in Section 3.2(a)(iii).

Mortgage Assignment means an assignment of the Mortgage in recordable form, sufficient under the laws of the jurisdiction wherein the related Mortgaged Property is located to reflect the sale of the Mortgage.

Trademark Assignment Agreement has the meaning set forth in Section 2.01.

Patent Assignment Agreement means the Patent Assignment Agreement attached hereto as Exhibit G.

Intellectual Property Assignment Agreement means, with respect to each Specified Business, an agreement in form and substance reasonably acceptable to Seller and Buyer, providing for the assignment of the Transferred Intellectual Property Related to such Specified Business.

Assignment / job means the work to be performed by the Consultant pursuant to the Contract.

Lease Assignments means the assignments of real property leases and subleases by and between a member of the Nuance Group, as assignor, and a member of the SpinCo Group, as assignee, in each case as set forth on Schedule XII under the caption “Lease Assignments.”

Collateral Assignment means, with respect to any Contracts, the original instrument of collateral assignment of such Contracts by the Company, as Seller, to the Collateral Agent, substantially in the form included in Exhibit A hereto.

Assignment/Amendment We reserve the right to change this Service Agreement (including the price or to charge an additional fee) and to delegate any of Our obligations at Our sole discretion provided We give You thirty (30) days’ prior written notice of the changes. The changes will become effective thirty (30) days after We send You the notice. If You do not like the changes, You may cancel this Service Agreement. You may not change this Service Agreement or delegate any of Your obligations. Should certain terms or conditions in this Service Agreement be held to be invalid or unenforceable, the remainder of the terms and conditions in this Service Agreement shall remain valid. Transfer: This Service Agreement is not transferable by You. Responsibility for benefits owed to You: This is not an insurance policy; it is a Service Agreement. HomeServe will serve as Your point-of-contact for all questions or concerns. Our obligations under this Service Agreement are insured under a service contract reimbursement insurance policy. If We fail to pay or to deliver service on a claim within sixty (60) days after proof of loss has been filed, or in the event You cancel this Service Agreement and We fail to issue any applicable refund within sixty (60) days after cancellation, You are entitled to make a claim against the insurer, Virginia Surety Company, Inc., 000 Xxxx Xxxxxxx Xxxx., 11th Floor, Chicago, IL 60604, 0-000-000-0000. Our Liability: To the extent permitted by applicable law, (1) You agree that We and HomeServe, and both of our parents, successors, affiliates, approved technicians and our and their officers, directors, employees, affiliates, agents and contractors shall not be liable to You or anyone else for: (a) any actual losses or direct damages that exceed the lowest applicable per covered repair benefit limit set out above; or (b) any amount of any form of indirect, special, punitive, incidental or consequential losses or damages, including those caused by any fault, failure, delay or defect in providing services under this Service Agreement, and (2) these limitations and waivers shall apply to all claims and all liabilities and shall survive the cancellation or expiration of this Service Agreement. You may have other rights that vary from state to state. Arbitration: YOU, NAW AND HOMESERVE ALL AGREE TO RESOLVE DISPUTES ONLY BY FINAL AND BINDING ARBITRATION OR IN SMALL CLAIMS COURT as follows:

Assignment Agreements The following Assignment, Assumption and Recognition Agreements, each dated as of March 29, 2006, whereby certain Servicing Agreements solely with respect to the related Mortgage Loans were assigned to the Depositor for the benefit of the Certificateholders:

Trademark Assignment shall have the meaning specified in Section 3.2(c).

Permitted Loan Purchase Assignment and Acceptance means an assignment and acceptance entered into by a Lender as an Assignor and Holdings, the Borrower or any of the Subsidiaries as an Assignee, as accepted by the Administrative Agent (if required by Section 9.04) in the form of Exhibit F or such other form as shall be approved by the Administrative Agent and the Borrower (such approval not to be unreasonably withheld or delayed).

Charterparty Assignment means, in relation to a Ship, the deed of assignment of any Charterparty in favour of the Security Trustee, in such form as the Lenders may approve or require;

Collateral Assignments means, collectively, the Assignment of the Development Agreement, and the Assignment of Management Agreement, the Assignment of the Right to Receive Tax Credits, Capital Contributions and Partnership Interests, each in form and substance satisfactory to the Significant Bondholder and the Financial Monitor and as each may be amended or supplemented from time to time with the prior written consent of the Significant Bondholder.

Assignment Agreement means an Assignment and Assumption Agreement substantially in the form of Exhibit E, with such amendments or modifications as may be approved by Administrative Agent.

Long Term Supply Assignment means, in relation to an employee,

Patent Assignment each patent collateral assignment agreement pursuant to which an Obligor assigns to Agent, for the benefit of Secured Parties, such Obligor’s interests in its patents, as security for the Obligations.

ClinicalTrials.gov Results Data Element Definitions for Interventional and Observational Studies

Note : The term "clinical study" is used to refer to both interventional and observational studies. The term "participant" is used to refer to a human subject.

Note : Outcome measure information from the Protocol Section of the record will be copied into the Results Section the first time results are created.

• Not Applicable (only if Measure Type is "Number," "Count of Participants," or "Count of Units")
• Standard Deviation
• Standard Error
• Inter-Quartile Range
• 80% Confidence Interval
• 90% Confidence Interval
• 95% Confidence Interval
• 97.5% Confidence Interval
• 99% Confidence Interval
• Other Confidence Interval Level
• Geometric Coefficient of Variation (only when Measure Type is "Geometric Mean")
• Superiority
• Non-inferiority
• Equivalence
• Other (for example, single group or other descriptive analysis)
• Non-Inferiority or Equivalence ( legacy selection )
• Superiority or Other ( legacy selection )
• Chi-Squared
• Chi-Squared, Corrected
• Cochran-Mantel-Haenszel
• Fisher Exact
• Kruskal-Wallis
• Mantel Haenszel
• Mixed Models Analysis
• Regression, Cox
• Regression, Linear
• Regression, Logistic
• t-Test, 1-Sided
• t-Test, 2-Sided
• Wilcoxon (Mann-Whitney)

Serious Adverse Events: * A table of all anticipated and unanticipated serious adverse events, grouped by organ system, with the number and frequency of such events by arm or comparison group of the clinical study. ( See Adverse Events definition below ).

• Other (Not Including Serious) Adverse Events: Adverse events that are not Serious Adverse Events.
• Blood and Lymphatic System Disorders
• Cardiac Disorders
• Congenital, Familial and Genetic Disorders
• Ear and Labyrinth Disorders
• Endocrine Disorders
• Eye Disorders
• Gastrointestinal Disorders
• General Disorders
• Hepatobiliary Disorders
• Immune System Disorders
• Infections and Infestations
• Injury, Poisoning and Procedural Complications
• Investigations
• Metabolism and Nutrition Disorders
• Musculoskeletal and Connective Tissue Disorders
• Neoplasms Benign, Malignant and Unspecified (Including Cysts and Polyps)
• Nervous System Disorders
• Pregnancy, Puerperium and Perinatal Conditions
• Product Issues
• Psychiatric Disorders
• Renal and Urinary Disorders
• Reproductive System and Breast Disorders
• Respiratory, Thoracic and Mediastinal Disorders
• Skin and Subcutaneous Tissue Disorders
• Social Circumstances
• Surgical and Medical Procedures
• Vascular Disorders
• Yes: The principal investigator is an employee of the sponsor
• No: The principal investigator is not an employee of the sponsor
• The only disclosure restriction on the PI is that the sponsor can review results communications prior to public release and can embargo communications regarding study results for a period that is less than or equal to 60 days from the date that the communication is submitted to the sponsor for review. The sponsor cannot require changes to the communication and cannot unilaterally extend the embargo.
• The only disclosure restriction on the PI is that the sponsor can review results communications prior to public release and can embargo communications regarding study results for a period that is more than 60 days but less than or equal to 180 days from the date that the communication is submitted to the sponsor for review. The sponsor cannot require changes to the communication and cannot unilaterally extend the embargo.
• Other disclosure agreement that restricts the right of the PI to disclose, discuss, or publish study results after the study is completed
• Certify Initial Approval: Trial studies an FDA-regulated drug product (including a biological product) or device product that was not approved, licensed or cleared by FDA for any use before the Primary Completion Date of the trial, and the sponsor intends to continue with product development and is either seeking, or may at a future date seek, FDA approval, licensure, or clearance of the drug product (including a biological product) or device product under study.
• Certify New Use: Trial studies an FDA-regulated drug product (including a biological product) or device product that previously has been approved, licensed, or cleared, for which the manufacturer is the sponsor of the trial and for which an application or premarket notification seeking approval, licensure, or clearance of the use being studied (which is not included in the labeling of the approved, licensed, or cleared drug, product (including a biologic product) or device product) has been filed or will be filed within one year with FDA.
• Extension: Request, for good cause, an extension of the deadline for submitting results information

Note : If a responsible party who is both the manufacturer of the drug product (including a biological product) or device product studied in an applicable clinical trial and the sponsor of the applicable clinical trial submits a certification under "Certify New Use," that responsible party must submit such a certification for each applicable clinical trial that meets the following criteria: (1) the applicable clinical trial is required to be submitted in an application or premarket notification seeking approval, licensure, or clearance of a new use; (2) the applicable clinical trial studies the same drug product (including a biological product) or device product for the same use as studied in the applicable clinical trial for which the initial certification was submitted. [42 U.S.C. 282 (j)(3)(E)(v)(II) and 42 CFR 11.44(b)(3)]

Intervention Name(s) Definition: Provide the name of one or more drugs, biological products or devices to which the certification applies. For drugs use generic name; for other types of interventions provide a brief descriptive name. The name(s) entered should match Intervention Name(s) provided in the protocol section.

FDA Application Number(s) Definition: Provide at least one FDA application number (for example, NDA, BLA, or PMA number), if available, when Delay Results Type is "Certify Initial Approval" or "Certify New Use."

Requested Submission Date [*] ( Required when Delay Results Type is "Extension." ) Definition: Estimate of the date on which the clinical study results information will be submitted, if the Delay Results Type is "Extension".

Explanation [*] ( Required when Delay Results Type is "Extension." ) Definition: Description of the reason(s) why clinical study results information cannot be provided according to the deadline, with sufficient detail to justify good cause for the extension and to allow for the evaluation of the request. Such detail includes reason(s) for the extension and proposed requested submission date, steps that will be taken to meet the requested submission date, a description of mitigating steps to avoid future delay, and any other information needed to address the criteria in Section III of the NIH Good Cause Extension Request Process and Criteria document. Note that "pending publication" and delays in data analysis without sufficient explanation are not considered good cause for an extension. Limit: 999 characters.

Appeal Justification [*] ( Required for a responsible party to file an appeal regarding an NIH decision to deny a request to extend the deadline for submitting results information [for good cause] or grant an earlier deadline than specified in the extension request ) Definition: An explanation of the reason(s) why the initial decision to deny the GCE request or grant the GCE request with a shorter deadline than requested should be overturned or revised, with sufficient detail to allow for the evaluation of the appeal. Only provide further elaboration of the grounds for the request or highlight factors that justify an extension and why the initial decision was incorrect. Note that new bases for an extension request should not be presented for the first time in an appeal and will not be considered. Limit: 999 characters.

• The full study protocol and statistical analysis plan must be uploaded as part of results information submission, for studies with a Primary Completion Date on or after January 18, 2017. The protocol and statistical analysis plan may be optionally uploaded before results information submission and updated with new versions, as needed. Informed consent forms may optionally be uploaded at any time.
• Each document must include a cover page with the Official Title of the study, NCT number (if available), and date of the document.
• Uploaded study documents should be the most recent version reviewed by a human subjects protection review board (if applicable).
• Documents must be uploaded in Portable Document Format Archival (PDF/A) format. It is strongly encouraged that the PDF/A file also be consistent with the PDF Universal Accessibility (PDF/UA) format, to optimize accessibility.
• For each uploaded document, provide the following information.
• Study Protocol: The written description of the clinical study, including objective(s), design, and methods. It may also include relevant scientific background and statistical considerations (if the protocol document includes the statistical analysis plan, use "Study Protocol with SAP and/or ICF" option). Note: All amendments approved by a human subjects protection review board (if applicable), before the time of submission and that apply to all clinical trial Facility Locations must be included.
• Statistical Analysis Plan (SAP): The written description of the statistical considerations for analyzing the data collected in the study. Includes how data are analyzed, what specific statistical methods are used for each analysis, and how adjustments are made for testing multiple variables. If some analysis methods require critical assumptions, the written description should allow data users to understand how those assumptions were verified.
• Informed Consent Form (ICF): The final version of the legal document approved by a human subjects protection review board. It is written in lay language and describes, among other things, the study’s purpose, procedures, risks and potential benefits.
• Study Protocol with SAP and/or ICF: The study protocol that also includes a statistical analysis plan (SAP) and/or an informed consent form (ICF). Select one or both. Statistical Analysis Plan (SAP) Informed Consent Form (ICF)
• January 18, 2017:  Document updated with data element changes per the FDAAA 801 final rule (42 CFR Part 11).
• April 18, 2017:  Modified Outcome Measure Description definition to describe when the Description is required.
• June 29, 2017:  Added Document Upload Information data elements as Appendix 1 (A.1.).
• March 22, 2018: Clarified that Document Upload Information (Study Protocol, Statistical Analysis Plan, Informed Consent Form) should be the version reviewed by a human subjects protection review board (if applicable) and must include a cover page.
• June 27, 2018:  Minor editorial changes.
• October 1, 2020:  Increased field lengths.
• February 01, 2021:  Document updated for 8. Delayed Results.
• February 08, 2023:  Document updated for 8. Delayed Results.
• June 05, 2023:  Document updated for 1. Participant Flow.

Pre-assignment

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Pre-assignment of project team members can occur for a few reasons. Sometimes specific people are identified in an agreement with a customer or partner. Another reason for pre-assignment is to plan human resource management for the future or over multiple projects or activities. This is most likely when someone has skills or knowledge that are rare or in high demand. Some organization require pre-assignment as a way of determining whether it will be necessary to hire or contract for additional staff or to delay the project until the right staff will be available.

Pre-assignment is a potential technique used in the PMI process to acquire project teams .

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Definition of assignment

task , duty , job , chore , stint , assignment mean a piece of work to be done.

task implies work imposed by a person in authority or an employer or by circumstance.

duty implies an obligation to perform or responsibility for performance.

job applies to a piece of work voluntarily performed; it may sometimes suggest difficulty or importance.

chore implies a minor routine activity necessary for maintaining a household or farm.

stint implies a carefully allotted or measured quantity of assigned work or service.

assignment implies a definite limited task assigned by one in authority.

Examples of assignment in a Sentence

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'assignment.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

see assign entry 1

14th century, in the meaning defined at sense 1

Phrases Containing assignment

• self - assignment

Dictionary Entries Near assignment

Cite this entry.

“Assignment.” Merriam-Webster.com Dictionary , Merriam-Webster, https://www.merriam-webster.com/dictionary/assignment. Accessed 6 Jun. 2024.

Legal Definition

Legal definition of assignment, more from merriam-webster on assignment.

Nglish: Translation of assignment for Spanish Speakers

Britannica English: Translation of assignment for Arabic Speakers

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Created by the Great Schools Partnership , the GLOSSARY OF EDUCATION REFORM is a comprehensive online resource that describes widely used school-improvement terms, concepts, and strategies for journalists, parents, and community members. | Learn more »

In education, the term  assessment  refers to the wide variety of methods or tools that educators use to evaluate, measure, and document the academic readiness, learning progress, skill acquisition, or educational needs of students.

While assessments are often equated with traditional tests—especially the standardized tests  developed by testing companies and administered to large populations of students—educators use a diverse array of assessment tools and methods to measure everything from a four-year-old’s readiness for kindergarten to a twelfth-grade student’s comprehension of advanced physics. Just as academic lessons have different functions, assessments are typically designed to measure specific elements of learning—e.g., the level of knowledge a student already has about the concept or skill the teacher is planning to teach or the ability to comprehend and analyze different types of texts and readings. Assessments also are used to identify individual student weaknesses and strengths so that educators can provide specialized  academic support , educational programming, or social services. In addition, assessments are developed by a wide array of groups and individuals, including teachers, district administrators, universities, private companies, state departments of education, and groups that include a combination of these individuals and institutions.

While assessment can take a wide variety of forms in education, the following descriptions provide a representative overview of a few major forms of educational assessment.

Assessments are used for a wide variety of purposes in schools and education systems :

• High-stakes  assessments  are typically standardized tests used for the purposes of accountability—i.e., any attempt by federal, state, or local government agencies to ensure that students are enrolled in effective schools and being taught by effective teachers. In general, “high stakes” means that important decisions about students, teachers, schools, or districts are based on the scores students achieve on a high-stakes test, and either punishments (sanctions, penalties, reduced funding, negative publicity, not being promoted to the next grade, not being allowed to graduate) or accolades (awards, public celebration, positive publicity, bonuses, grade promotion, diplomas) result from those scores. For a more detailed discussion, see  high-stakes test .
• Pre-assessments  are administered before students begin a lesson, unit, course, or academic program. Students are not necessarily expected to know most, or even any, of the material evaluated by pre-assessments—they are generally used to (1) establish a baseline against which educators measure learning progress over the duration of a program, course, or instructional period, or (2) determine general academic readiness for a course, program, grade level, or new academic program that student may be transferring into.
• Formative  assessments  are in-process evaluations of student learning that are typically administered multiple times during a unit, course, or academic program. The general purpose of formative assessment is to give educators in-process feedback about what students are learning or not learning so that instructional approaches, teaching materials, and academic support can be modified accordingly. Formative assessments are usually not scored or graded, and they may take a variety of forms, from more formal quizzes and assignments to informal questioning techniques and in-class discussions with students.

Formative assessments are commonly said to be  for  learning because educators use the results to modify and improve teaching techniques during an instructional period, while summative assessments are said to be  of  learning because they evaluate academic achievement at the conclusion of an instructional period. Or as assessment expert Paul Black put it, “When the cook tastes the soup, that’s formative assessment. When the customer tastes the soup, that’s summative assessment.”

• Interim assessments   are used to evaluate where students are in their learning progress and determine whether they are on track to performing well on future assessments, such as standardized tests, end-of-course exams, and other forms of “summative” assessment. Interim assessments are usually administered periodically during a course or school year (for example, every six or eight weeks) and separately from the process of instructing students (i.e., unlike formative assessments, which are integrated into the instructional process).
• Placement assessments  are used to “place” students into a course, course level, or academic program. For example, an assessment may be used to determine whether a student is ready for Algebra I or a higher-level algebra course, such as an honors-level course. For this reason, placement assessments are administered before a course or program begins, and the basic intent is to match students with appropriate learning experiences that address their distinct learning needs.
• Screening assessments  are used to determine whether students may need specialized assistance or services, or whether they are ready to begin a course, grade level, or academic program. Screening assessments may take a wide variety of forms in educational settings, and they may be developmental, physical, cognitive, or academic. A preschool screening test, for example, may be used to determine whether a young child is physically, emotionally, socially, and intellectually ready to begin preschool, while other screening tests may be used to evaluate health, potential learning disabilities, and other student attributes.

Assessments are also designed in a variety of ways for different purposes:

• Standardized assessments  are designed, administered, and scored in a standard, or consistent, manner. They often use a multiple-choice format, though some include open-ended, short-answer questions. Historically, standardized tests featured rows of ovals that students filled in with a number-two pencil, but increasingly the tests are computer-based. Standardized tests can be administered to large student populations of the same age or grade level in a state, region, or country, and results can be compared across individuals and groups of students. For a more detailed discussion, see  standardized test .
• Standards-referenced or standards-based  assessments  are designed to measure how well students have mastered the specific knowledge and skills described in local, state, or national  learning standards . Standardized tests and high-stakes tests may or may not be based on specific learning standards, and individual schools and teachers may develop their own standards-referenced or standards-based assessments. For a more detailed discussion, see  proficiency-based learning .
• Common  assessments  are used in a school or district to ensure that all teachers are evaluating student performance in a more consistent, reliable, and effective manner. Common assessments are used to encourage greater consistency in teaching and assessment among teachers who are responsible for teaching the same content, e.g. within a grade level, department, or  content area . They allow educators to compare performance results across multiple classrooms, courses, schools, and/or learning experiences (which is not possible when educators teach different material and individually develop their own distinct assessments). Common assessments share the same format and are administered in consistent ways—e.g., teachers give students the same instructions and the same amount of time to complete the assessment, or they use the same scoring guides to interpret results. Common assessments may be “formative” or “summative .” For more detailed discussions, see coherent curriculum  and  rubric .
• Performance assessments  typically require students to complete a complex task, such as a writing assignment, science experiment, speech, presentation, performance, or long-term project, for example. Educators will often use collaboratively developed common assessments, scoring guides, rubrics, and other methods to evaluate whether the work produced by students shows that they have learned what they were expected to learn. Performance assessments may also be called “authentic assessments,” since they are considered by some educators to be more accurate and meaningful evaluations of learning achievement than traditional tests. For more detailed discussions, see authentic learning ,  demonstration of learning , and  exhibition .
• Portfolio-based  assessments  are collections of academic work—for example, assignments, lab results, writing samples, speeches, student-created films, or art projects—that are compiled by students and assessed by teachers in consistent ways. Portfolio-based assessments are often used to evaluate a “body of knowledge”—i.e., the acquisition of diverse knowledge and skills over a period of time. Portfolio materials can be collected in physical or digital formats, and they are often evaluated to determine whether students have met required learning standards . For a more detailed discussion, see  portfolio .

The purpose of an assessment generally drives the way it is designed, and there are many ways in which assessments can be used. A standardized assessment can be a high-stakes assessment, for example, but so can other forms of assessment that are not standardized tests. A portfolio of student work can be a used as both a “formative” and “summative” form of assessment. Teacher-created assessments, which may also be created by teams of teachers, are commonly used in a single course or grade level in a school, and these assessments are almost never “high-stakes.” Screening assessments may be produced by universities that have conducted research on a specific area of child development, such as the skills and attributes that a student should have when entering kindergarten to increase the likelihood that he or she will be successful, or the pattern of behaviors, strengths, and challenges that suggest a child has a particular learning disability. In short, assessments are usually created for highly specialized purposes.

While educational assessments and tests have been around since the days of the one-room schoolhouse, they have increasingly assumed a central role in efforts to improve the effectiveness of public schools and teaching. Standardized-test scores, for example, are arguably the dominant measure of educational achievement in the United States, and they are also the most commonly reported indicator of school, teacher, and school-system performance.

As schools become increasingly equipped with computers, tablets, and wireless internet access, a growing proportion of the assessments now administered in schools are either computer-based or online assessments—though paper-based tests and assessments are still common and widely used in schools. New technologies and software applications are also changing the nature and use of assessments in innumerable ways, given that digital-assessment systems typically offer an array of features that traditional paper-based tests and assignments cannot. For example, online-assessment systems may allow students to log in and take assessments during out-of-class time or they may make performance results available to students and teachers immediately after an assessment has been completed (historically, it might have taken hours, days, or weeks for teachers to review, score, and grade all assessments for a class). In addition, digital and online assessments typically include features, or “analytics,” that give educators more detailed information about student performance. For example, teachers may be able to see how long it took students to answer particular questions or how many times a student failed to answer a question correctly before getting the right answer. Many advocates of digital and online assessments tend to argue that such systems, if used properly, could help teachers “ personalize ” instruction—because many digital and online systems can provide far more detailed information about the academic performance of students, educators can use this information to modify educational programs, learning experiences , instructional approaches, and  academic-support strategies  in ways that address the distinct learning needs, interests, aspirations, or cultural backgrounds of individual students. In addition, many large-scale standardized tests are now administered online, though states typically allow students to take paper-based tests if computers are unavailable, if students prefer the paper-based option, or if students don’t have the technological skills and literacy required to perform well on an online assessment.

Given that assessments come in so many forms and serve so many diverse functions, a thorough discussion of the purpose and use of assessments could fill a lengthy book. The following descriptions, however, provide a brief, illustrative overview of a few of the major ways in which assessments—especially assessment results—are used in an attempt to improve schools and teaching:

• System and school accountability : Assessments, particularly standardized tests, have played an increasingly central role in efforts to hold schools, districts, and state public-school systems “accountable” for improving the academic achievement of students. The most widely discussed and far-reaching example, the 2001 federal law commonly known as the No Child Left Behind Act, strengthened federal expectations from the 1990s and required each state develop  learning standards   to govern what teachers should teach and students should learn. Under No Child Left Behind, standards are required in every grade level and  content area  from kindergarten through high school. The law also requires that students be tested annually in grades 3-8 and at least once in grades 10-12 in reading and mathematics. Since the law’s passage, standardized tests have been developed and implemented to measure how well students were meeting the standards, and scores have been reported publicly by state departments of education. The law also required that test results be tracked and reported separately for different “subgroups” of students, such as minority students, students from low-income households, students with special needs, and students with  limited proficiency in English . By publicly reporting the test scores achieved by different schools and student groups, and by tying those scores to penalties and funding, the law has aimed to close  achievement gaps  and improve schools that were deemed to be underperforming. While the No Child Left Behind Act is one of the most controversial and contentious educational policies in recent history, and the technicalities of the legislation are highly complex, it is one example of how assessment results are being used as an accountability measure.
• Teacher evaluation and compensation : In recent years, a growing number of elected officials, policy makers, and education reformers have argued that the best way to improve educational results is to ensure that students have effective teachers, and that one way to ensure effective teaching is to evaluate and compensate educators, at least in part, based on the test scores their students achieve. By basing a teacher’s income and job security on assessment results, the reasoning goes, administrators can identify and reward high-performing teachers or take steps to either help low-performing teachers improve or remove them from schools. Growing political pressure, coupled with the promise of federal grants, prompted many states to begin using student test results in teacher evaluations. This controversial and highly contentious reform strategy generally requires fairly complicated statistical techniques—known as  value-added measures   or  growth measures —to determine how much of a positive or negative effect individual teachers have on the academic achievement of their students, based primarily on student assessment results.
• Instructional improvement : Assessment results are often used as a mechanism for improving instructional quality and student achievement. Because assessments are designed to measure the acquisition of specific knowledge or skills, the design of an assessment can determine or influence what gets taught in the classroom (“teaching to the test” is a common, and often derogatory, phrase used to describe this general phenomenon). Formative assessments, for example, give teachers in-process feedback on student learning, which can help them make instructional adjustments during the teaching process, instead of having to wait until the end of a unit or course to find out how well students are learning the material. Other forms of assessment, such as standards-based assessments or common assessments, encourage educators to teach similar material and evaluate student performance in more consistent, reliable, or comparable ways.
• Learning-needs identification : Educators use a wide range of assessments and assessment methods to identify specific student learning needs, diagnose learning disabilities (such as autism, dyslexia, or nonverbal learning disabilities), evaluate language ability, or determine eligibility for specialized educational services. In recent years, the early identification of specialized learning needs and disabilities, and the proactive provision of educational support services to students, has been a major focus of numerous educational reform strategies. For a related discussion, see  academic support .

In education, there is widespread agreement that assessment is an integral part of any effective educational system or program. Educators, parents, elected officials, policy makers, employers, and the public all want to know whether students are learning successfully and progressing academically in school. The debates—many of which are a complex, wide ranging, and frequently contentious—typically center on how assessments are used, including how frequently they are being administered and whether assessments are beneficial or harmful to students and the teaching process. While a comprehensive discussion of these debates is beyond the scope of this resource, the following is a representative selection of a few major issues being debated:

• Is high-stakes testing, as an accountability measure, the best way to improve schools, teaching quality, and student achievement? Or do the potential consequences—such as teachers focusing mainly on test preparation and a narrow range of knowledge at the expense of other important skills, or increased incentives to cheat and manipulate test results—undermine the benefits of using test scores as a way to hold schools and educators more accountable and improve educational results?
• Are standardized assessments truly  objective  measures of academic achievement? Or do they reflect intrinsic biases—in their design or content—that favor some students over others, such wealthier white students from more-educated households over minority and low-income students from less-educated households? For more detailed discussions, see  measurement error and  test bias .
• Are “one-size-fits-all” standardized tests a fair way to evaluate the learning achievement of all students, given that some students may be better test-takers than others? Or should students be given a variety of assessment options and multiple opportunities to demonstrate what they have learned?
• Will more challenging and  rigorous   assessments lead to higher educational achievement for all students? Or will they end up penalizing certain students who come from disadvantaged backgrounds? And, conversely, will less-advantaged students be at an even greater disadvantage if they are not held to the same high educational standards as other students (because lowering educational standards for certain students, such as students of color, will only further disadvantage them and perpetuate the same cycle of low expectations that historically contributed to racial and socioeconomic  achievement gaps )?
• Do the costs—in money, time, and human resources—outweigh the benefits of widespread, large-scale testing? Would the funding and resources invested in testing and accountability be better spent on higher-quality educational materials, more training and support for teachers, and other resources that might improve schools and teaching more effectively? And is the pervasive use of tests providing valuable information that educators can use to improve instructional quality and student learning? Or are the tests actually taking up time that might be better spent on teaching students more knowledge and skills?
• Are technological learning applications, including digital and online assessments, improving learning experiences for students, teaching them technological skills and literacy, or generally making learning experiences more interesting and engaging? Or are digital learning applications adding to the cost of education, introducing unwanted distractions in schools, or undermining the value of teachers and the teaching process?

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Random Assignment in Psychology: Definition & Examples

Julia Simkus

Editor at Simply Psychology

BA (Hons) Psychology, Princeton University

Julia Simkus is a graduate of Princeton University with a Bachelor of Arts in Psychology. She is currently studying for a Master's Degree in Counseling for Mental Health and Wellness in September 2023. Julia's research has been published in peer reviewed journals.

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Saul Mcleod, PhD

Editor-in-Chief for Simply Psychology

BSc (Hons) Psychology, MRes, PhD, University of Manchester

Saul Mcleod, PhD., is a qualified psychology teacher with over 18 years of experience in further and higher education. He has been published in peer-reviewed journals, including the Journal of Clinical Psychology.

Olivia Guy-Evans, MSc

Associate Editor for Simply Psychology

BSc (Hons) Psychology, MSc Psychology of Education

Olivia Guy-Evans is a writer and associate editor for Simply Psychology. She has previously worked in healthcare and educational sectors.

In psychology, random assignment refers to the practice of allocating participants to different experimental groups in a study in a completely unbiased way, ensuring each participant has an equal chance of being assigned to any group.

In experimental research, random assignment, or random placement, organizes participants from your sample into different groups using randomization. 

Random assignment uses chance procedures to ensure that each participant has an equal opportunity of being assigned to either a control or experimental group.

The control group does not receive the treatment in question, whereas the experimental group does receive the treatment.

When using random assignment, neither the researcher nor the participant can choose the group to which the participant is assigned. This ensures that any differences between and within the groups are not systematic at the onset of the study. 

In a study to test the success of a weight-loss program, investigators randomly assigned a pool of participants to one of two groups.

Group A participants participated in the weight-loss program for 10 weeks and took a class where they learned about the benefits of healthy eating and exercise.

Group B participants read a 200-page book that explains the benefits of weight loss. The investigator randomly assigned participants to one of the two groups.

The researchers found that those who participated in the program and took the class were more likely to lose weight than those in the other group that received only the book.

Importance 

Random assignment ensures that each group in the experiment is identical before applying the independent variable.

In experiments , researchers will manipulate an independent variable to assess its effect on a dependent variable, while controlling for other variables. Random assignment increases the likelihood that the treatment groups are the same at the onset of a study.

Thus, any changes that result from the independent variable can be assumed to be a result of the treatment of interest. This is particularly important for eliminating sources of bias and strengthening the internal validity of an experiment.

Random assignment is the best method for inferring a causal relationship between a treatment and an outcome.

Random Selection vs. Random Assignment 

Random selection (also called probability sampling or random sampling) is a way of randomly selecting members of a population to be included in your study.

On the other hand, random assignment is a way of sorting the sample participants into control and treatment groups. 

Random selection ensures that everyone in the population has an equal chance of being selected for the study. Once the pool of participants has been chosen, experimenters use random assignment to assign participants into groups. 

Random assignment is only used in between-subjects experimental designs, while random selection can be used in a variety of study designs.

Random Assignment vs Random Sampling

Random sampling refers to selecting participants from a population so that each individual has an equal chance of being chosen. This method enhances the representativeness of the sample.

Random assignment, on the other hand, is used in experimental designs once participants are selected. It involves allocating these participants to different experimental groups or conditions randomly.

This helps ensure that any differences in results across groups are due to manipulating the independent variable, not preexisting differences among participants.

When to Use Random Assignment

Random assignment is used in experiments with a between-groups or independent measures design.

In these research designs, researchers will manipulate an independent variable to assess its effect on a dependent variable, while controlling for other variables.

There is usually a control group and one or more experimental groups. Random assignment helps ensure that the groups are comparable at the onset of the study.

How to Use Random Assignment

There are a variety of ways to assign participants into study groups randomly. Here are a handful of popular methods: 

• Random Number Generator : Give each member of the sample a unique number; use a computer program to randomly generate a number from the list for each group.
• Lottery : Give each member of the sample a unique number. Place all numbers in a hat or bucket and draw numbers at random for each group.
• Flipping a Coin : Flip a coin for each participant to decide if they will be in the control group or experimental group (this method can only be used when you have just two groups) 
• Roll a Die : For each number on the list, roll a dice to decide which of the groups they will be in. For example, assume that rolling 1, 2, or 3 places them in a control group and rolling 3, 4, 5 lands them in an experimental group.

When is Random Assignment not used?

• When it is not ethically permissible: Randomization is only ethical if the researcher has no evidence that one treatment is superior to the other or that one treatment might have harmful side effects. 
• When answering non-causal questions : If the researcher is just interested in predicting the probability of an event, the causal relationship between the variables is not important and observational designs would be more suitable than random assignment. 
• When studying the effect of variables that cannot be manipulated: Some risk factors cannot be manipulated and so it would not make any sense to study them in a randomized trial. For example, we cannot randomly assign participants into categories based on age, gender, or genetic factors.

Drawbacks of Random Assignment

While randomization assures an unbiased assignment of participants to groups, it does not guarantee the equality of these groups. There could still be extraneous variables that differ between groups or group differences that arise from chance. Additionally, there is still an element of luck with random assignments.

Thus, researchers can not produce perfectly equal groups for each specific study. Differences between the treatment group and control group might still exist, and the results of a randomized trial may sometimes be wrong, but this is absolutely okay.

Scientific evidence is a long and continuous process, and the groups will tend to be equal in the long run when data is aggregated in a meta-analysis.

Additionally, external validity (i.e., the extent to which the researcher can use the results of the study to generalize to the larger population) is compromised with random assignment.

Random assignment is challenging to implement outside of controlled laboratory conditions and might not represent what would happen in the real world at the population level. 

Random assignment can also be more costly than simple observational studies, where an investigator is just observing events without intervening with the population.

Randomization also can be time-consuming and challenging, especially when participants refuse to receive the assigned treatment or do not adhere to recommendations. 

What is the difference between random sampling and random assignment?

Random sampling refers to randomly selecting a sample of participants from a population. Random assignment refers to randomly assigning participants to treatment groups from the selected sample.

Does random assignment increase internal validity?

Yes, random assignment ensures that there are no systematic differences between the participants in each group, enhancing the study’s internal validity .

Does random assignment reduce sampling error?

Yes, with random assignment, participants have an equal chance of being assigned to either a control group or an experimental group, resulting in a sample that is, in theory, representative of the population.

Random assignment does not completely eliminate sampling error because a sample only approximates the population from which it is drawn. However, random sampling is a way to minimize sampling errors. 

When is random assignment not possible?

Random assignment is not possible when the experimenters cannot control the treatment or independent variable.

For example, if you want to compare how men and women perform on a test, you cannot randomly assign subjects to these groups.

Participants are not randomly assigned to different groups in this study, but instead assigned based on their characteristics.

Does random assignment eliminate confounding variables?

Yes, random assignment eliminates the influence of any confounding variables on the treatment because it distributes them at random among the study groups. Randomization invalidates any relationship between a confounding variable and the treatment.

Why is random assignment of participants to treatment conditions in an experiment used?

Random assignment is used to ensure that all groups are comparable at the start of a study. This allows researchers to conclude that the outcomes of the study can be attributed to the intervention at hand and to rule out alternative explanations for study results.

Further Reading

• Bogomolnaia, A., & Moulin, H. (2001). A new solution to the random assignment problem .  Journal of Economic theory ,  100 (2), 295-328.
• Krause, M. S., & Howard, K. I. (2003). What random assignment does and does not do .  Journal of Clinical Psychology ,  59 (7), 751-766.

Related Articles

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What Is a Focus Group?

Cross-Cultural Research Methodology In Psychology

What Is Internal Validity In Research?

Research Methodology , Statistics

What Is Face Validity In Research? Importance & How To Measure

Criterion Validity: Definition & Examples

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[ uh - sahyn ]

verb (used with object)

to assign rooms at a hotel.

to assign homework.

to assign one to guard duty.

to assign a day for a meeting.

Synonyms: determine , fix

to assign a cause.

Synonyms: offer , show , advance , allege , adduce

to assign a contract.

• Military. to place permanently on duty with a unit or under a commander.

verb (used without object)

• Law. to transfer property, especially in trust or for the benefit of creditors.

my heirs and assigns.

to assign an expert to the job

to assign advertising to an expert

to assign a day for the meeting

to assign a stone cross to the Vikings

• to transfer (one's right, interest, or title to property) to someone else
• also intr law (formerly) to transfer (property) to trustees so that it may be used for the benefit of creditors
• military to allocate (men or materials) on a permanent basis Compare attach
• computing to place (a value corresponding to a variable) in a memory location
• law a person to whom property is assigned; assignee

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Derived forms.

• asˈsigner , noun
• asˈsignably , adverb
• asˌsignaˈbility , noun
• asˈsignable , adjective

Other Words From

• as·signer Chiefly Law. as·sign·or [ uh, -sahy-, nawr, as-, uh, -, nawr ] , noun
• misas·sign verb
• nonas·signed adjective
• preas·sign verb (used with object)
• preas·signed adjective
• reas·sign verb (used with object)
• self-as·signed adjective
• unas·signed adjective
• well-as·signed adjective

Word History and Origins

Origin of assign 1

Synonym Study

Example sentences.

It is designed to listen to meetings with multiple participants and will parse discussion patterns to produce informative synopses and assign post-meeting action items.

Such randomized, double-blinded controlled trials randomly assign patients to receive a drug or a placebo, and don’t reveal to participants or doctors who is getting which.

That AI could pore over an astronaut’s symptoms and then recommend medical tests, make diagnoses and assign treatments.

So I rose beyond cleaning, to working as an operational dispatcher for cabin services in the American Airlines traffic control center, assign cleaning crews to each incoming aircraft.

Ideally, the Mars spaceship would be equipped with artificial intelligence that could consider an astronaut’s symptoms, recommend medical tests, make diagnoses and assign treatments.

Now the Kremlin will assign more loyal people to rule the region, mostly military leaders.

When we assign a primitive “not me” status to another individual or social group, it can—and does—take us down a destructive path.

Other folks can debate and assign blame for “who lost Iraq.”

Renee Richardson knows she'll likely never be able to assign blame for her son's death—she's done fighting for that.

Girls are directed through several pages of this until they are asked to assign the guy a series of pre-decided adjectives.

The designs of Russia have long been proverbial; but the exercise of the new art of printing may assign them new features.

With what honest pride did John Smith, the best farmer of them all, step to the fore and assign to each man his place!

If the lessee die, his executor or administrator can assign the remainder of his term.

As the lessee may assign or sublet unless forbidden, so may the lessor part with his interest in the leased premises.

If offered any dish of which you do not wish to partake, decline it, but do not assign any reason.

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Prewriting for Composition

Glossary of Grammatical and Rhetorical Terms

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• An Introduction to Punctuation
• Ph.D., Rhetoric and English, University of Georgia
• M.A., Modern English and American Literature, University of Leicester
• B.A., English, State University of New York

In composition , the term prewriting refers to any activity that helps a writer think about a topic , determine a purpose , analyze an audience , and prepare to write . Prewriting is closely related to the art of invention in classical rhetoric .

"The objective of prewriting," according to Roger Caswell and Brenda Mahler, "is to prepare students for writing by allowing them to discover what they know and what else they need to know. Prewriting invites exploration and promotes the motivation to write" ( Strategies for Teaching Writing , 2004).

Because various kinds of writing (such as note-taking , listing, and freewriting) usually occur during this stage of the writing process, the term  prewriting  is somewhat misleading. A number of teachers and researchers prefer the term exploratory writing .

See Examples and Observations below. Also, see:

• Writing Process
• Discovery Strategies (Heuristics)
• George Carlin on Finding Something to Write About
• Your Writing: Private and Public

Types of Prewriting Activities

• Brainstorming
• Freewriting
• Journalists' Questions
• Journal Writing

Examples and Observations

• "Prewriting is the 'getting ready to write' stage. The traditional notion that writers have a topic completely thought out and ready to flow onto the page is ridiculous. Writers begin tentatively—talking, reading, brainstorming—to see what they know and in what direction they want to go." -Gail Tompkins, Rod Campbell, and David Green,  Literacy for the 21st Century . Pearson Australia, 2010
• "Prewriting involves anything you do to help yourself decide what your central idea is or what details, examples, reasons, or content you will include. Freewriting, brainstorming, and clustering . . . are types of prewriting. Thinking, talking to other people, reading related material, outlining or organizing ideas—all are forms of prewriting. Obviously, you can prewrite at any time in the writing process. Whenever you want to think up new material, simply stop what you are doing and start using one of [these] techniques..." -Stephen McDonald and William Salomone, The Writer's Response , 5th ed. Wadsworth, 2012

The Aims of Prewriting "Usually, the prewriting activities help you find a good topic, narrow topics that are too broad, and look at purpose. You should finish the prewriting activities with at least a sentence and a list . Or you may have something as formal as a three-part thesis sentence and a fully developed outline. Either way, you'll have laid the groundwork." -Sharon Sorenson, Webster's New World Student Writing Handbook . Wiley, 2010

Prewriting as a Method of Discovery "Jeannette Harris stresses prewriting while stating that discovery occurs throughout the composing process, even in revision , when the writer is still 'retrieving additional information, making further connections, recognizing emerging patterns' [ Expressive Discourse , 15]. In prewriting as well as free-writing and keeping journals, ideas and forms are discovered by provoking memory. In addition, the personal nature of much prewriting and freewriting serve as an affirmation that the memory of the student writer has a valid place in the writing classroom." -Janine Rider, The Writer's Book of Memory: An Interdisciplinary Study for Writing Teachers . Routledge, 1995

Prewriting and Revising "[P]rewriting plans are not carved in stone; they are simply tools for generating and organizing ideas. Writers frequently change their minds as they write, eliminating some details , adding and changing others. That's why some writers say that 'prewriting' is a misnomer; they return to their plans over and over during all stages of the writing process, often revising and adjusting the plans as they go." -Lori Jamison Rog,  Marvelous Minilessons for Teaching Intermediate Writing . International Reading Association, 2011

• Examples of Great Introductory Paragraphs
• The Prewriting Stage of the Writing Process
• The Use of Listing in Composition
• How to Explore Ideas Through Clustering
• Definition and Examples of Paragraphing in Essays
• Focusing in Composition
• Discover Ideas Through Brainstorming
• Discovery Strategy for Freewriting
• dramatism (rhetoric and composition)
• Writer-Based Prose
• A Writing Portfolio Can Help You Perfect Your Writing Skills
• Heuristics in Rhetoric and Composition
• The Whys and How-tos for Group Writing in All Content Areas
• Thesis: Definition and Examples in Composition
• Peer Response (Composition)
• Explore and Evaluate Your Writing Process

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12.2: Pre-experimental and quasi-experimental design

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• Page ID 25667

• Matthew DeCarlo
• Radford University via Open Social Work Education

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Learning Objectives

• Identify and describe the various types of quasi-experimental designs
• Distinguish true experimental designs from quasi-experimental and pre-experimental designs
• Identify and describe the various types of quasi-experimental and pre-experimental designs

As we discussed in the previous section, time, funding, and ethics may limit a researcher’s ability to conduct a true experiment. For researchers in the medical sciences and social work, conducting a true experiment could require denying needed treatment to clients, which is a clear ethical violation. Even those whose research may not involve the administration of needed medications or treatments may be limited in their ability to conduct a classic experiment. When true experiments are not possible, researchers often use quasi-experimental designs.

Quasi-experimental designs are similar to true experiments, but they lack random assignment to experimental and control groups. The most basic of these quasi-experimental designs is the nonequivalent comparison groups design (Rubin & Babbie, 2017). [1] The nonequivalent comparison group design looks a lot like the classic experimental design, except it does not use random assignment. In many cases, these groups may already exist. For example, a researcher might conduct research at two different agency sites, one of which receives the intervention and the other does not. No one was assigned to treatment or comparison groups. Those groupings existed prior to the study. While this method is more convenient for real-world research, researchers cannot be sure that the groups are comparable. Perhaps the treatment group has a characteristic that is unique–for example, higher income or different diagnoses–that make the treatment more effective.

Quasi-experiments are particularly useful in social welfare policy research. Social welfare policy researchers like me often look for what are termed natural experiments , or situations in which comparable groups are created by differences that already occur in the real world. For example, Stratmann and Wille (2016) [2] were interested in the effects of a state healthcare policy called Certificate of Need on the quality of hospitals. They clearly cannot assign states to adopt one set of policies or another. Instead, researchers used hospital referral regions, or the areas from which hospitals draw their patients, that spanned across state lines. Because the hospitals were in the same referral region, researchers could be pretty sure that the client characteristics were pretty similar. In this way, they could classify patients in experimental and comparison groups without affecting policy or telling people where to live.

There are important examples of policy experiments that use random assignment, including the Oregon Medicaid experiment. In the Oregon Medicaid experiment, the wait list for Oregon was so long, state officials conducted a lottery to see who from the wait list would receive Medicaid (Baicker et al., 2013). [3] Researchers used the lottery as a natural experiment that included random assignment. People selected to be a part of Medicaid were the experimental group and those on the wait list were in the control group. There are some practical complications with using people on a wait list as a control group—most obviously, what happens when people on the wait list are accepted into the program while you’re still collecting data? Natural experiments aren’t a specific kind of experiment like quasi- or pre-experimental designs. Instead, they are more like a feature of the social world that allows researchers to use the logic of experimental design to investigate the connection between variables.

Matching is another approach in quasi-experimental design to assigning experimental and comparison groups. Researchers should think about what variables are important in their study, particularly demographic variables or attributes that might impact their dependent variable. Individual matching involves pairing participants with similar attributes. When this is done at the beginning of an experiment, the matched pair is split—with one participant going to the experimental group and the other to the control group. An ex post facto control group , in contrast, is when a researcher matches individuals after the intervention is administered to some participants. Finally, researchers may engage in aggregate matching , in which the comparison group is determined to be similar on important variables.

There are many different quasi-experimental designs in addition to the nonequivalent comparison group design described earlier. Describing all of them is beyond the scope of this textbook, but one more design is worth mentioning. The time series design uses multiple observations before and after an intervention. In some cases, experimental and comparison groups are used. In other cases where that is not feasible, a single experimental group is used. By using multiple observations before and after the intervention, the researcher can better understand the true value of the dependent variable in each participant before the intervention starts. Additionally, multiple observations afterwards allow the researcher to see whether the intervention had lasting effects on participants. Time series designs are similar to single-subjects designs, which we will discuss in Chapter 15.

When true experiments and quasi-experiments are not possible, researchers may turn to a pre-experimental design (Campbell & Stanley, 1963). [4] Pre-experimental designs are called such because they often happen before a true experiment is conducted. Researchers want to see if their interventions will have some effect on a small group of people before they seek funding and dedicate time to conduct a true experiment. Pre-experimental designs, thus, are usually conducted as a first step towards establishing the evidence for or against an intervention. However, this type of design comes with some unique disadvantages, which we’ll describe as we review the pre-experimental designs available.

If we wished to measure the impact of a natural disaster, such as Hurricane Katrina for example, we might conduct a pre-experiment by identifying an experimental group from a community that experienced the hurricane and a control group from a similar community that had not been hit by the hurricane. This study design, called a static group comparison , has the advantage of including a comparison group that did not experience the stimulus (in this case, the hurricane). Unfortunately, it is difficult to know those groups are truly comparable because the experimental and control groups were determined by factors other than random assignment. Additionally, the design would only allow for posttests, unless one were lucky enough to be gathering the data already before Katrina. As you might have guessed from our example, static group comparisons are useful in cases where a researcher cannot control or predict whether, when, or how the stimulus is administered, as in the case of natural disasters.

In cases where the administration of the stimulus is quite costly or otherwise not possible, a one- shot case study design might be used. In this instance, no pretest is administered, nor is a control group present. In our example of the study of the impact of Hurricane Katrina, a researcher using this design would test the impact of Katrina only among a community that was hit by the hurricane and would not seek a comparison group from a community that did not experience the hurricane. Researchers using this design must be extremely cautious about making claims regarding the effect of the stimulus, though the design could be useful for exploratory studies aimed at testing one’s measures or the feasibility of further study.

Finally, if a researcher is unlikely to be able to identify a sample large enough to split into control and experimental groups, or if she simply doesn’t have access to a control group, the researcher might use a one-group pre-/posttest design. In this instance, pre- and posttests are both taken, but there is no control group to which to compare the experimental group. We might be able to study of the impact of Hurricane Katrina using this design if we’d been collecting data on the impacted communities prior to the hurricane. We could then collect similar data after the hurricane. Applying this design involves a bit of serendipity and chance. Without having collected data from impacted communities prior to the hurricane, we would be unable to employ a one- group pre-/posttest design to study Hurricane Katrina’s impact.

As implied by the preceding examples where we considered studying the impact of Hurricane Katrina, experiments do not necessarily need to take place in the controlled setting of a lab. In fact, many applied researchers rely on experiments to assess the impact and effectiveness of various programs and policies. You might recall our discussion of arresting perpetrators of domestic violence in Chapter 6, which is an excellent example of an applied experiment. Researchers did not subject participants to conditions in a lab setting; instead, they applied their stimulus (in this case, arrest) to some subjects in the field and they also had a control group in the field that did not receive the stimulus (and therefore were not arrested).

Key Takeaways

• Quasi-experimental designs do not use random assignment.
• Comparison groups are often used in quasi-experiments.
• Matching is a way of improving the comparability of experimental and comparison groups.
• Quasi-experimental designs and pre-experimental designs are often used when experimental designs are impractical.
• Quasi-experimental and pre-experimental designs may be easier to carry out, but they lack the rigor of true experiments.
• Aggregate matching- when the comparison group is determined to be similar to the experimental group along important variables
• Ex post facto control group- a control group created when a researcher matches individuals after the intervention is administered
• Individual matching- pairing participants with similar attributes for the purpose of assignment to groups
• Natural experiments- situations in which comparable groups are created by differences that already occur in the real world
• Nonequivalent comparison group design- a quasi-experimental design similar to a classic experimental design but without random assignment
• One-group pre-/posttest design- a pre-experimental design that applies an intervention to one group but also includes a pretest
• One-shot case study- a pre-experimental design that applies an intervention to only one group without a pretest
• Pre-experimental designs- a variation of experimental design that lacks the rigor of experiments and is often used before a true experiment is conducted
• Quasi-experimental design- designs lack random assignment to experimental and control groups
• Static group design- uses an experimental group and a comparison group, without random assignment and pretesting
• Time series design- a quasi-experimental design that uses multiple observations before and after an intervention

Image attributions

cat and kitten matching avocado costumes on the couch looking at the camera by Your Best Digs CC-BY-2.0

• Rubin, C. & Babbie, S. (2017). Research methods for social work (9th edition) . Boston, MA: Cengage. ↵
• Stratmann, T. & Wille, D. (2016). Certificate-of-need laws and hospital quality . Mercatus Center at George Mason University, Arlington, VA. Retrieved from: https://www.mercatus.org/system/files/mercatus-stratmann-wille-con-hospital-quality-v1.pdf ↵
• Baicker, K., Taubman, S. L., Allen, H. L., Bernstein, M., Gruber, J. H., Newhouse, J. P., ... & Finkelstein, A. N. (2013). The Oregon experiment—effects of Medicaid on clinical outcomes. New England Journal of Medicine , 368 (18), 1713-1722. ↵
• Campbell, D., & Stanley, J. (1963). Experimental and quasi-experimental designs for research . Chicago, IL: Rand McNally. ↵

Read the Code of Ethics

The NASW Code of Ethics is a set of standards that guide the professional conduct of social workers. The 2021 update includes language that addresses the importance of professional self-care. Moreover, revisions to Cultural Competence standard provide more explicit guidance to social workers. All social workers should review the new text and affirm their commitment to abide by the Code of Ethics. Also available in Spanish.

• The first Section, "Preamble," summarizes the social work profession's mission and core values.
• The second section, Purpose of the NASW Code of Ethics , provides an overview of the Code's main functions and a brief guide for dealing with ethical issues or dilemmas in social work practice.
• The third section, Ethical Principles , presents broad ethical principles, based on social work's core values, that inform social work practice.
• The final section, Ethical Standards , includes specific ethical standards to guide social workers' conduct and to provide a basis for adjudication.

The primary mission of the social work profession is to enhance human well-being and help meet the basic human needs of all people, with particular attention to the needs and empowerment of people who are vulnerable, oppressed, and living in poverty. A historic and defining feature of social work is the profession’s dual focus on individual well-being in a social context and the well-being of society. Fundamental to social work is attention to the environmental forces that create, contribute to, and address problems in living.

Social workers promote social justice and social change with and on behalf of clients. “Clients” is used inclusively to refer to individuals, families, groups, organizations, and communities. Social workers are sensitive to cultural and ethnic diversity and strive to end discrimination, oppression, poverty, and other forms of social injustice. These activities may be in the form of direct practice, community organizing, supervision, consultation, administration, advocacy, social and political action, policy development and implementation, education, and research and evaluation. Social workers seek to enhance the capacity of people to address their own needs. Social workers also seek to promote the responsiveness of organizations, communities, and other social institutions to individuals’ needs and social problems.

The mission of the social work profession is rooted in a set of core values. These core values, embraced by social workers throughout the profession’s history, are the foundation of social work’s unique purpose and perspective:

• social justice
• dignity and worth of the person
• importance of human relationships
• competence.

This constellation of core values reflects what is unique to the social work profession. Core values, and the principles that flow from them, must be balanced within the context and complexity of the human experience.

Purpose of the NASW Code of Ethics

Professional ethics are at the core of social work. The profession has an obligation to articulate its basic values, ethical principles, and ethical standards. The NASW Code of Ethics sets forth these values, principles, and standards to guide social workers’ conduct. The Code is relevant to all social workers and social work students, regardless of their professional functions, the settings in which they work, or the populations they serve.

The NASW Code of Ethics serves six purposes:

• The Code identifies core values on which social work’s mission is based.
• The Code summarizes broad ethical principles that reflect the profession’s core values and establishes a set of specific ethical standards that should be used to guide social work practice.
• The Code is designed to help social workers identify relevant considerations when professional obligations conflict or ethical uncertainties arise.
• The Code provides ethical standards to which the general public can hold the social work profession accountable.
• The Code socializes practitioners new to the field to social work’s mission, values, ethical principles, and ethical standards, and encourages all social workers to engage in self-care, ongoing education, and other activities to ensure their commitment to those same core features of the profession.
• The Code articulates standards that the social work profession itself can use to assess whether social workers have engaged in unethical conduct. NASW has formal procedures to adjudicate ethics complaints filed against its members.* In subscribing to this Code, social workers are required to cooperate in its implementation, participate in NASW adjudication proceedings, and abide by any NASW disciplinary rulings or sanctions based on it.

The Code offers a set of values, principles, and standards to guide decision making and conduct when ethical issues arise. It does not provide a set of rules that prescribe how social workers should act in all situations. Specific applications of the Code must take into account the context in which it is being considered and the possibility of conflicts among the Code’s values, principles, and standards. Ethical responsibilities flow from all human relationships, from the personal and familial to the social and professional.

* For information on the NASW Professional Review Process, see NASW Procedures for Professional Review.

Furthermore, the NASW Code of Ethics does not specify which values, principles, and standards are most important and ought to outweigh others in instances when they conflict. Reasonable differences of opinion can and do exist among social workers with respect to the ways in which values, ethical principles, and ethical standards should be rank ordered when they conflict. Ethical decision making in a given situation must apply the informed judgment of the individual social worker and should also consider how the issues would be judged in a peer review process where the ethical standards of the profession would be applied.

Ethical decision making is a process. In situations when conflicting obligations arise, social workers may be faced with complex ethical dilemmas that have no simple answers. Social workers should take into consideration all the values, principles, and standards in this Code that are relevant to any situation in which ethical judgment is warranted. Social workers’ decisions and actions should be consistent with the spirit as well as the letter of this Code.

In addition to this Code, there are many other sources of information about ethical thinking that may be useful. Social workers should consider ethical theory and principles generally, social work theory and research, laws, regulations, agency policies, and other relevant codes of ethics, recognizing that among codes of ethics social workers should consider the NASW Code of Ethics as their primary source. Social workers also should be aware of the impact on ethical decision making of their clients’ and their own personal values and cultural and religious beliefs and practices. They should be aware of any conflicts between personal and professional values and deal with them responsibly. For additional guidance social workers should consult the relevant literature on professional ethics and ethical decision making and seek appropriate consultation when faced with ethical dilemmas. This may involve consultation with an agency-based or social work organization’s ethics committee, a regulatory body, knowledgeable colleagues, supervisors, or legal counsel.

Instances may arise when social workers’ ethical obligations conflict with agency policies or relevant laws or regulations. When such conflicts occur, social workers must make a responsible effort to resolve the conflict in a manner that is consistent with the values, principles, and standards expressed in this Code. If a reasonable resolution of the conflict does not appear possible, social workers should seek proper consultation before making a decision. The NASW Code of Ethics is to be used by NASW and by individuals, agencies, organizations, and bodies (such as licensing and regulatory boards, professional liability insurance providers, courts of law, agency boards of directors, government agencies, and other professional groups) that choose to adopt it or use it as a frame of reference. Violation of standards in this Code does not automatically imply legal liability or violation of the law.

Such determination can only be made in the context of legal and judicial proceedings. Alleged violations of the Code would be subject to a peer review process. Such processes are generally separate from legal or administrative procedures and insulated from legal review or proceedings to allow the profession to counsel and discipline its own members.

A code of ethics cannot guarantee ethical behavior. Moreover, a code of ethics cannot resolve all ethical issues or disputes or capture the richness and complexity involved in striving to make responsible choices within a moral community. Rather, a code of ethics sets forth values, ethical principles, and ethical standards to which professionals aspire and by which their actions can be judged. Social workers' ethical behavior should result from their personal commitment to engage in ethical practice. The NASW Code of Ethics reflects the commitment of all social workers to uphold the profession’s values and to act ethically. Principles and standards must be applied by individuals of good character who discern moral questions and, in good faith, seek to make reliable ethical judgments.

With growth in the use of communication technology in various aspects of social work practice, social workers need to be aware of the unique challenges that may arise in relation to the maintenance of confidentiality, informed consent, professional boundaries, professional competence, record keeping, and other ethical considerations. In general, all ethical standards in this Code of Ethics are applicable to interactions, relationships, or communications, whether they occur in person or with the use of technology. For the purposes of this Code, “technology-assisted social work services” include any social work services that involve the use of computers, mobile or landline telephones, tablets, video technology, or other electronic or digital technologies; this includes the use of various electronic or digital platforms, such as the Internet, online social media, chat rooms, text messaging, e-mail and emerging digital applications. Technology-assisted social work services encompass all aspects of social work practice, including psychotherapy; individual, family, or group counseling; community organization; administration; advocacy; mediation; education; supervision; research; evaluation; and other social work services. Social workers should keep apprised of emerging technological developments that may be used in social work practice and how various ethical standards apply to them.

Professional self-care is paramount for competent and ethical social work practice. Professional demands, challenging workplace climates, and exposure to trauma warrant that social workers maintain personal and professional health, safety, and integrity. Social work organizations, agencies, and educational institutions are encouraged to promote organizational policies, practices, and materials to support social workers’ self-care.

Ethical Principles

The following broad ethical principles are based on social work’s core values of service, social justice, dignity and worth of the person, importance of human relationships, integrity, and competence. These principles set forth ideals to which all social workers should aspire.

Value: Service Ethical Principle: Social workers’ primary goal is to help people in need and to address social problems

Social workers elevate service to others above self-interest. Social workers draw on their knowledge, values, and skills to help people in need and to address social problems. Social workers are encouraged to volunteer some portion of their professional skills with no expectation of significant financial return (pro bono service).

Value: Social Justice Ethical Principle: Social workers challenge social injustice.

Social workers pursue social change, particularly with and on behalf of vulnerable and oppressed individuals and groups of people. Social workers’ social change efforts are focused primarily on issues of poverty, unemployment, discrimination, and other forms of social injustice. These activities seek to promote sensitivity to and knowledge about oppression and cultural and ethnic diversity. Social workers strive to ensure access to needed information, services, and resources; equality of opportunity; and meaningful participation in decision making for all people.

Value: Dignity and Worth of the Person Ethical Principle: Social workers respect the inherent dignity and worth of the person.

Social workers treat each person in a caring and respectful fashion, mindful of individual differences and cultural and ethnic diversity. Social workers promote clients’ socially responsible self-determination. Social workers seek to enhance clients’ capacity and opportunity to change and to address their own needs. Social workers are cognizant of their dual responsibility to clients and to the broader society. They seek to resolve conflicts between clients’ interests and the broader society’s interests in a socially responsible manner consistent with the values, ethical principles, and ethical standards of the profession.

Value: Importance of Human Relationships Ethical Principle: Social workers recognize the central importance of human relationships.

Social workers understand that relationships between and among people are an important vehicle for change. Social workers engage people as partners in the helping process. Social workers seek to strengthen relationships among people in a purposeful effort to promote, restore, maintain, and enhance the well-being of individuals, families, social groups, organizations, and communities.

Value: Integrity Ethical Principle: Social workers behave in a trustworthy manner.

Social workers are continually aware of the profession’s mission, values, ethical principles, and ethical standards and practice in a manner consistent with them. Social workers should take measures to care for themselves professionally and personally. Social workers act honestly and responsibly and promote ethical practices on the part of the organizations with which they are affiliated.

Value: Competence Ethical Principle: Social workers practice within their areas of competence and develop and enhance their professional expertise.

Social workers continually strive to increase their professional knowledge and skills and to apply them in practice. Social workers should aspire to contribute to the knowledge base of the profession.

Ethical Standards

The following ethical standards are relevant to the professional activities of all social workers. These standards concern (1) social workers’ ethical responsibilities to clients, (2) social workers’ ethical responsibilities to colleagues, (3) social workers’ ethical responsibilities in practice settings, (4) social workers’ ethical responsibilities as professionals, (5) social workers’ ethical responsibilities to the social work profession, and (6) social workers’ ethical responsibilities to the broader society. Some of the standards that follow are enforceable guidelines for professional conduct, and some are aspirational. The extent to which each standard is enforceable is a matter of professional judgment to be exercised by those responsible for reviewing alleged violations of ethical standards.

1. Social Workers' Ethical Responsibilities to Clients >>

2. social workers' ethical responsibilities to colleagues >>, 3. social workers' ethical responsibilities in practice settings >>, 4. social workers' ethical responsibilities as professionals >>, 5. social workers' ethical responsibilities to the social work profession >>, 6. social workers' ethical responsibilities to the broader society >>.

Revised Code of Ethics

• Order a copy of the Code of Ethics
• Order a copy of Código de Ética (Spanish version)

About the Revisions

• 2021 Highlighted Revisions to the Code of Ethics
• Frequently Asked Questions

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8.2 Quasi-experimental and pre-experimental designs

Learning objectives.

• Identify and describe the various types of quasi-experimental designs
• Distinguish true experimental designs from quasi-experimental and pre-experimental designs
• Identify and describe the various types of quasi-experimental and pre-experimental designs

As we discussed in the previous section, time, funding, and ethics may limit a researcher’s ability to conduct a true experiment. For researchers in the medical sciences and social work, conducting a true experiment could require denying needed treatment to clients, which is a clear ethical violation. Even those whose research may not involve the administration of needed medications or treatments may be limited in their ability to conduct a classic experiment. When true experiments are not possible, researchers often use quasi-experimental designs.

Quasi-experimental designs

Quasi-experimental designs are similar to true experiments, but they lack random assignment to experimental and control groups. Quasi-experimental designs have a comparison group that is similar to a control group except assignment to the comparison group is not determined by random assignment. The most basic of these quasi-experimental designs is the nonequivalent comparison groups design (Rubin & Babbie, 2017).  The nonequivalent comparison group design looks a lot like the classic experimental design, except it does not use random assignment. In many cases, these groups may already exist. For example, a researcher might conduct research at two different agency sites, one of which receives the intervention and the other does not. No one was assigned to treatment or comparison groups. Those groupings existed prior to the study. While this method is more convenient for real-world research, it is less likely that that the groups are comparable than if they had been determined by random assignment. Perhaps the treatment group has a characteristic that is unique–for example, higher income or different diagnoses–that make the treatment more effective.

Quasi-experiments are particularly useful in social welfare policy research. Social welfare policy researchers often look for what are termed natural experiments , or situations in which comparable groups are created by differences that already occur in the real world. Natural experiments are a feature of the social world that allows researchers to use the logic of experimental design to investigate the connection between variables. For example, Stratmann and Wille (2016) were interested in the effects of a state healthcare policy called Certificate of Need on the quality of hospitals. They clearly could not randomly assign states to adopt one set of policies or another. Instead, researchers used hospital referral regions, or the areas from which hospitals draw their patients, that spanned across state lines. Because the hospitals were in the same referral region, researchers could be pretty sure that the client characteristics were pretty similar. In this way, they could classify patients in experimental and comparison groups without dictating state policy or telling people where to live.

Matching is another approach in quasi-experimental design for assigning people to experimental and comparison groups. It begins with researchers thinking about what variables are important in their study, particularly demographic variables or attributes that might impact their dependent variable. Individual matching involves pairing participants with similar attributes. Then, the matched pair is split—with one participant going to the experimental group and the other to the comparison group. An ex post facto control group , in contrast, is when a researcher matches individuals after the intervention is administered to some participants. Finally, researchers may engage in aggregate matching , in which the comparison group is determined to be similar on important variables.

Time series design

There are many different quasi-experimental designs in addition to the nonequivalent comparison group design described earlier. Describing all of them is beyond the scope of this textbook, but one more design is worth mentioning. The time series design uses multiple observations before and after an intervention. In some cases, experimental and comparison groups are used. In other cases where that is not feasible, a single experimental group is used. By using multiple observations before and after the intervention, the researcher can better understand the true value of the dependent variable in each participant before the intervention starts. Additionally, multiple observations afterwards allow the researcher to see whether the intervention had lasting effects on participants. Time series designs are similar to single-subjects designs, which we will discuss in Chapter 15.

Pre-experimental design

When true experiments and quasi-experiments are not possible, researchers may turn to a pre-experimental design (Campbell & Stanley, 1963).  Pre-experimental designs are called such because they often happen as a pre-cursor to conducting a true experiment.  Researchers want to see if their interventions will have some effect on a small group of people before they seek funding and dedicate time to conduct a true experiment. Pre-experimental designs, thus, are usually conducted as a first step towards establishing the evidence for or against an intervention. However, this type of design comes with some unique disadvantages, which we’ll describe below.

A commonly used type of pre-experiment is the one-group pretest post-test design . In this design, pre- and posttests are both administered, but there is no comparison group to which to compare the experimental group. Researchers may be able to make the claim that participants receiving the treatment experienced a change in the dependent variable, but they cannot begin to claim that the change was the result of the treatment without a comparison group.   Imagine if the students in your research class completed a questionnaire about their level of stress at the beginning of the semester.  Then your professor taught you mindfulness techniques throughout the semester.  At the end of the semester, she administers the stress survey again.  What if levels of stress went up?  Could she conclude that the mindfulness techniques caused stress?  Not without a comparison group!  If there was a comparison group, she would be able to recognize that all students experienced higher stress at the end of the semester than the beginning of the semester, not just the students in her research class.

In cases where the administration of a pretest is cost prohibitive or otherwise not possible, a one- shot case study design might be used. In this instance, no pretest is administered, nor is a comparison group present. If we wished to measure the impact of a natural disaster, such as Hurricane Katrina for example, we might conduct a pre-experiment by identifying  a community that was hit by the hurricane and then measuring the levels of stress in the community.  Researchers using this design must be extremely cautious about making claims regarding the effect of the treatment or stimulus. They have no idea what the levels of stress in the community were before the hurricane hit nor can they compare the stress levels to a community that was not affected by the hurricane.  Nonetheless, this design can be useful for exploratory studies aimed at testing a measures or the feasibility of further study.

In our example of the study of the impact of Hurricane Katrina, a researcher might choose to examine the effects of the hurricane by identifying a group from a community that experienced the hurricane and a comparison group from a similar community that had not been hit by the hurricane. This study design, called a static group comparison , has the advantage of including a comparison group that did not experience the stimulus (in this case, the hurricane). Unfortunately, the design only uses for post-tests, so it is not possible to know if the groups were comparable before the stimulus or intervention.  As you might have guessed from our example, static group comparisons are useful in cases where a researcher cannot control or predict whether, when, or how the stimulus is administered, as in the case of natural disasters.

As implied by the preceding examples where we considered studying the impact of Hurricane Katrina, experiments, quasi-experiments, and pre-experiments do not necessarily need to take place in the controlled setting of a lab. In fact, many applied researchers rely on experiments to assess the impact and effectiveness of various programs and policies. You might recall our discussion of arresting perpetrators of domestic violence in Chapter 2, which is an excellent example of an applied experiment. Researchers did not subject participants to conditions in a lab setting; instead, they applied their stimulus (in this case, arrest) to some subjects in the field and they also had a control group in the field that did not receive the stimulus (and therefore were not arrested).

Key Takeaways

• Quasi-experimental designs do not use random assignment.
• Comparison groups are used in quasi-experiments.
• Matching is a way of improving the comparability of experimental and comparison groups.
• Quasi-experimental designs and pre-experimental designs are often used when experimental designs are impractical.
• Quasi-experimental and pre-experimental designs may be easier to carry out, but they lack the rigor of true experiments.
• Aggregate matching – when the comparison group is determined to be similar to the experimental group along important variables
• Comparison group – a group in quasi-experimental design that does not receive the experimental treatment; it is similar to a control group except assignment to the comparison group is not determined by random assignment
• Ex post facto control group – a control group created when a researcher matches individuals after the intervention is administered
• Individual matching – pairing participants with similar attributes for the purpose of assignment to groups
• Natural experiments – situations in which comparable groups are created by differences that already occur in the real world
• Nonequivalent comparison group design – a quasi-experimental design similar to a classic experimental design but without random assignment
• One-group pretest post-test design – a pre-experimental design that applies an intervention to one group but also includes a pretest
• One-shot case study – a pre-experimental design that applies an intervention to only one group without a pretest
• Pre-experimental designs – a variation of experimental design that lacks the rigor of experiments and is often used before a true experiment is conducted
• Quasi-experimental design – designs lack random assignment to experimental and control groups
• Static group design – uses an experimental group and a comparison group, without random assignment and pretesting
• Time series design – a quasi-experimental design that uses multiple observations before and after an intervention

Image attributions

cat and kitten   matching avocado costumes on the couch looking at the camera by Your Best Digs CC-BY-2.0

Foundations of Social Work Research Copyright © 2020 by Rebecca L. Mauldin is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License , except where otherwise noted.

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