Key Takeaways
- Face validity is the degree to which a measure appears to be measuring what it is intended to measure.
- It is important to consider face validity because participants may not take a study seriously if they do not believe that the measures used are relevant to the research objectives.
- Face validity is a convenient preliminary measure of validity. In many cases, it is a better measure when conducted by someone who is an expert in the measure’s content.
What Is Face Validity?
Face validity is the extent to which a test appears to measure what it is intended to measure (Johnson, 2021).
For example, a test of mathematical ability targeted at first-year university students would ideally be valid if it accurately and comprehensively assessed an individual’s mathematical skills through doing word problems drawing from all areas of math ranging from algebra to calculus.
However, a test that only assesses one’s skills in adding and subtracting would not be considered valid for measuring the mathematical ability of this group.
Furthermore, a test that includes items that are unrelated to mathematics (e.g., items assessing verbal ability) would also not be considered face-valid.
Face validity, unlike content validity, does not rely on established theory for support (Fink, 2010).
Why is face validity important in research?
Face validity is an important first step for measuring the overall validity of a test.
Although it can not determine whether or not a test actually works, it can give researchers an idea of whether or not the content and format of a test are appropriate for measuring the desired construct.
Tests that appear to be face valid can give participants and researchers alike confidence that the results of the assessment are fair and equitable (Johnson, 2021).
Face validity can be used to eliminate subpar research quickly. For example, a researcher reviewing a paper on the link between vaccinations and autism in children may reveal several shortcomings in the design of the experiment, causing the paper’s rejection of face validity.
Additionally, face validity is important for establishing other types of validity. It is necessary for establishing the content validity of a test, which is defined as “the extent to which a test covers all important aspects of the domain being measured” (Siraj et al., 2021).
How to measure face validity
There are a few different ways that researchers can measure the face validity of their test. One way is to ask participants to rate how relevant and important each item on the test is for measuring the desired construct.
Another way is to ask participants whether or not they think the test is a good measure of the construct (Fink, 2010).
Both of these methods have their advantages and disadvantages. For example, self-report measures may be influenced by participants’ own biases and beliefs about the construct being measured, as well as their level of familiarity with it.
For example, participants who have no idea what organic chemistry is may not be able to discern whether or not a test is a face-valid way of assessing knowledge of stereochemistry. As such, it is often best to use multiple methods for assessing face validity.
Who should measure face validity?
In general, face validity is a weaker measure of validity when done by the general public but can be stronger for an expert in the field.
In general, however, it is best to have multiple people measure face validity, as different people may have different perspectives on what is important for measuring a construct.
For example, a group of experts in organic chemistry may have different opinions about what content should be included in a test of stereochemistry than a group of first-year university students who are taking an introductory course on the topic (Fink, 2010).
It is also important to note that face validity is not static; that is, what is considered face valid for measuring a construct can change over time.
For example, a personality test measuring “masculinity” and “femininity” that was developed in the 1950s may not be considered valid today, as society’s understanding of gender has changed significantly since then. As such, it is important to review and update measures of face validity regularly.
When should you test face validity?
Face validity is often measured during the early stages of test development, as it can give researchers an idea of whether or not the content and format of a test are appropriate for measuring the desired construct.
However, it is important to note that face validity is only a preliminary step in assessing the overall validity of a test; other types of validity (e.g., content validity, predictive validity) must also be assessed in order to determine whether or not a test actually works (Fink, 2010).
FAQs
Is face validity internal or external?
Internal validity generally encompasses the validity of results within a study, while external validity pertains to the validity of applying study conclusions outside or external to the setting of a study.
Most experts agree that face validity is one factor in both internal and construct validity.
Face validity can help assess criterion validity — the extent to which items on a questionnaire are actually measuring the real-world states or events that they are intended to measure and a faucet of internal validity — as well as content validity — the extent to which items on a questionnaire adequately cover the construct being studied (McDermott, 2011).
How can face validity be improved?
There are a few things that can be done to increase the chances that a measure is perceived as having high face validity.
First, it is important to use clear and concise language when crafting items for the measure. If the items are confusing or difficult to understand, participants are likely to lose interest and engagement with the task.
Second, it is helpful to use familiar content and scenarios when possible. This will make it easier for participants to relate to the items and see how they might be relevant to their own lives.
Finally and most self-evidently, it is important to ensure that the items on the measure are actually measuring what they claim to be measuring.
If there is any discrepancy between the stated goals of the measure and the actual content of the items, this will likely decrease perceptions of face validity (Fink, 2010).
Why is face validity regarded as a convenience by researchers?
Face validity is considered to be more convenient than other types of validity because it is relatively easy and quick to establish.
All that is required is for an expert in the field to review the test content and make sure that it is relevant and comprehensive. Second, face validity can be determined without having to administer the test to anyone.
This is in contrast to types of validity that require test-takers to actually complete the assessment (e.g., convergent validity, discriminant validity) (Fink, 2010).
Is face validity the same as content validity?
Face validity is not the same as content validity. While face validity is the extent to which a measure appears to be measuring what it is supposed to be measuring, content validity is the extent to which a measure actually covers the construct it is supposed to be measuring.
Face validity is one of two methods for assessing content validity.
Of these measures, face validity is the least rigorous because the only process involved is reviewing the measure and making the determination of content validity based on the “face” of the measure — its appearance (Rubio, 2005)
How many experts are needed for face validity?
Logical validity is the other way of assessing the content validity of a measure.
This process involves having a panel of experts review the items on the measure and determine whether each item is an adequate representation of the concept being measured (Messick, 1995).
Unlike logical validity, however, face validity does not necessarily require multiple experts to assess. Indeed, face validity can be measured by asking a group of experts or layperson respondents how valid they believe a measure is.
References
Fink, A. Peterson, P. L., Baker, E., & McGaw, B. (2010). International encyclopedia of education. Elsevier Ltd..
Johnson, E. (2021). Face validity. In Encyclopedia of autism spectrum disorders (pp. 1957-1957). Cham: Springer International Publishing.
McDermott, R. (2011). Internal and external validity. Cambridge handbook of experimental political science, 27-40.
Messick, S. (1995). Standards of validity and the validity of standards in performance assessment. Educational measurement: Issues and practice, 14(4), 5-8.
Rubio, D. M. (2005). Content validity.
Siraj, S., Stark, W., McKinley, S. D., Morrison, J. M., & Sochet, A. A. (2021). The bronchiolitis severity score: An assessment of face validity, construct validity, and interobserver reliability. Pediatric pulmonology, 56(6), 1739-1744.