Testing clients with disabilities: Modifications vs. accommodations
March 28, 2023

During our recent PARtalks webinar series on assessing individuals with disabilities, PAR received some questions about adapting, modifying, and accommodating assessments. It is important to be mindful of a range of psychometric, social, clinical, and disability-related issues. We hope the following will provide helpful guidance when determining if modifications or accommodations are necessary.

Considerations when assessing individuals with disabilities

There are many issues to consider that may complicate the psychological testing of people with disabilities. It is important to attend to issues of bias, reliability, and validity.

Language,  motor, sensory, medical, and cognitive disabilities can impact aspects of an assessment. Additionally, comorbid conditions or secondary disabilities can be a complicating factor.

It is crucial for examiners to consider each individual's disability and how it relates to other functions to develop a strategy that ensures the appropriate construct is being measured. For example, disability-related symptoms such as fatigue and pain can confound psychometric tests and artificially inflate measures of depression. Or a motor-functioning disability that affects fine motor control may create results that mistakenly imply cognitive impairment. Examiners who do not take these issues into consideration risk drawing misleading inferences, making inaccurate conclusions, and offering unsuitable treatment recommendations.

How do you determine an assessment is suitable for a particular individual?

To determine if an instrument is suitable for use with a client with a disability, clinicians must evaluate if the measure(s) being considered are appropriate for use without introducing accessibility challenges. If the construct to be measured will be measured in a way that requires a specific functional ability that is related to the client’s disability, or if the measure’s administration instructions and response options are related to the client’s impairment, for example, another measure may be considered.   

The clinician should consider validity information regarding a measure’s use with people with specific disabilities, just as they would for any other population. Quantitative measures should be supplemented by qualitative and functional assessments. Before testing, it is important to meet with the client to understand disability-specific characteristics related to the constructs of interest. It is the clinician's responsibility to describe the assessment and subsequent results in terms that the client can easily understand.

When is it suitable to alter an assessment?

Any decisions to modify protocols requires thoughtful consideration and justification but may be useful ways to support individuals with disabilities. There are two types of alterations to testing, accommodations and modifications. Accommodations improve access to the test without affecting the construct being measured. Modifications may affect the construct and may influence validity.

  • Accommodations: A testing accommodation is a change in test format, presentation, administration, or response procedures. Accommodations do not alter the construct being measured and scores are comparable with the original test.

  • Modifications: Modifications are testing changes that may alter the intended construct. The purpose of a modification is to improve accessibility while retaining as much of the original construct as possible.

 Examples of accommodations and modifications

Accessibility means the ability to access, interact with, and respond appropriately to test content. It involves designing a measure in a way that reduces barriers to a valid assessment of a given construct. Accommodations and modifications are often made to increase accessibility, but if accessibility is designed into the structure of an instrument, they may not be required.

Determining the necessity of an accommodation depends on how the disability presents as well as the construct or constructs being assessed. Accommodations help clients with varying levels of ability by removing access barriers that might influence the individual’s results. However, accommodations do not alter the construct being measured.

Accommodations may be made to the environment or to the way a task is presented without changing the content of the task. An accommodation for a student with a visual impairment might be  enlarging print materials; an accommodation for a student who is deaf might be providing an ASL interpreter.

Modifications, however, can be changes that are made to the content or expectations of an assignment, task, or assessment. A student with a learning disability might receive a modification that reduces the number of questions on a test or provides untimed access to the materials. Modifications change what the individual is expected to learn or do in order to make it more accessible.

In general, modifications are more significant changes. Modifications alter what is expected of the individual; accommodations are less significant changes that provide support for the individual to access the same content and activities as their peers.

Resources on accommodations and modifications

Learn more about modifying psychological assessments for individuals with disabilities:

American Psychological Association (APA) Guidelines for Assessment and Intervention with Persons with Disabilities: APA has developed these guidelines to help psychologists develop and implement effective, fair, and ethical psychological assessments and interventions.

National Joint Committee on Learning Disabilities (NJCLD): The NJCLD has developed guidelines for the assessment of individuals with learning disabilities. The NJCLD offers recommendations for modifying psychological assessments.

National Association of School Psychologists (NASP): NASP offers advice and guidance on modifying assessments as well as evaluating the effectiveness of those interventions.

The PAR Training Portal. Catch up on the PARtalks disability series on the PAR Training Portal. Recorded webinars are available on demand to help you learn more about working with individuals with a variety of disabilities.