In discussing the advantages and disadvantages of face validity, we distinguish between those scenarios where (a) face validity is the main form of validity that you have used in your research, and where (b) face validity is used as a supplemental form of validity, supporting other types of validity (e.g., construct validity and/or content validity). We make this distinction because face validity is often discussed as though it is the main form of validity used during a piece of research, especially at the undergraduate and master's dissertation level. In such cases, face validity comes in for far more criticism than when used as a supplemental form of validity, where it can often help improve the measurement procedure being used. Let's look at the advantages and disadvantages of face validity in turn:
If face validity is your main form of validity
One of the practical reasons for using face validity as the main form of validity for your measurement procedure is that it is quick and easy to apply. Rather than having to investigate the underlying factors that determine whether a measure is robust, as you have to do when applying content validity or construct validity, it is easy and quick to come up with measures that are face valid. Often, you simply need to think what measures (e.g., questions in a questionnaire) would make sense to you if you were taking part in the research (i.e., if you were being asked the question).
If face validity is used as a supplemental form of validity
Unless there is a specific reason why you do not want a measure to appear to measure what it measures because this could affect the responses you get from participants in a negative way (e.g., the racial prejudice example above), it is a good thing that a measure has face validity. It can encourage people to respond (e.g. to a survey) because they imagine that the measurement procedure is measuring something it should be. Lack of such face validity can discourage people from taking part in a survey; or if they do take part, they may be more likely to drop out. Furthermore, if participants expect to benefit from the results in some way, perhaps because the results could bring about some type of change that is beneficial to them (e.g., a reduction of racial prejudice, an improvement in training techniques in the classroom, etc.), they are less likely to support a measurement procedure that they feel would not lead to a more predictable result.
For example, an organisation may conduct a study to measure employee motivation because they want to find the best ways of improving such motivation. However, if employees don't trust the different questions/items/measures of employee motivation that are displayed in the questionnaire that they fill out, they may be unwilling to engage in the research or trust the results. They may feel that items are missing that are important to them; that is, questions that they feel influence their motivation but are not included (e.g., questions about the physical working environment, flexible working arrangements, in addition to the standard questions about pay and rewards). They may feel that the employer/study creator has intentionally or unintentionally left out these questions.
Face validity helps to give participants greater confidence in the measurement procedure and the results. It can also give greater confidence to administrators/sponsors of the study; not just participants.
If face validity is your main form of validity
When used as the main form of validity for assessing a measurement procedure, face validity is the weakest form of validity. In fact, face validity is not real validity. Therefore, strong face validity does not equate to strong validity in general. After all, face validity is subjective (i.e., based on the subjective judgement of the researcher), and only provides the appearance of that a measurement procedure is valid. It cannot be quantified. In other words, you can't tell how well the measurement procedure measures what it is trying to measure, which is possible with other forms of validity (e.g., construct validity).
Sometimes you do not want research participants to understand/guess the purpose of a measurement procedure because this can affect the responses that they give in a negative way. This was highlighted when we spoke about measuring racial prejudice, where respondents desire to improve their self-image (i.e., how they are perceived by the researcher and others) leads them to respond differently than they would usually [see the example: Racial prejudice]. Whilst it is possible to try and disguise the purpose of the measurement procedure, reducing its face validity, there would be no point designing a measurement procedure that relies on face validity if you intended to do this.
If face validity is used as a supplemental form of validity
Even when face validity is being used as a supplemental form of validity, it can still be undesirable when you do not want research participants to understand/guess the purpose of the measurement procedure, as discussed in the previous section.
If you are using face validity as a supplemental form of validity, you may also be interested in our introductory articles to construct validity [see the article: Construct validity] and content validity [see the article: Content validity].
Balance-related tests
Bohannon, R. W., Larkin, P. A., Cook, A. C., Gear, J., & Singer, J. (1984). Decrease in timed balance test scores with aging. Physical Therapy, 64(7): 1067-1070.
Olmsted, L. C., Carcia, C. R., Hertel, J., & Shultz, S. J. (2002). Efficacy of the Star Excursion Balance Tests in detecting reach deficits in subjects with chronic ankle instability. Journal of Athletic Training, 37(4): 501-506.
Emotional intelligence measurement
Boyatzis, R. E., Goleman, D., & Hay/McBer. (1999). Emotional Competence Inventory. Boston, MA: HayGroup.
Goleman, D., Boyatzis, R., & McKee, A. (2002). Primal Leadership: Realizing the Power of Emotional Intelligence. Boston, MA: Harvard Business School Press.
Mayer, J. D., Caruso, D. R., & Salovey, P. (2000). Selecting a measure of emotional intelligence. In R. Bar-On & J.D.A. Parker (Eds.) The Handbook of Emotional Intelligence: Theory, Development, Assessment, and Application at Home, School, and in the Workplace. San Francisco: Jossey-Bass.
Mayer, J. D., & Geher, G. (1996). Emotional intelligence of emotional intelligence. Intelligence, 17: 433-422.
Anxiety-based measures
Beck, A. T., & Steer, R. A. (1990). Manual for the Beck Anxiety Inventory. San Antonio, TX: Psychological Corporation.
Kabacoff, R. I., Segal, D. L., Hersen, M., & Van Hasselt, V. B. (1997). Psychometric properties and diagnostic utility of the Beck Anxiety Inventory and the State-Trait Anxiety Inventory with older adult psychiatric outpatients. Journal of Anxiety Disorders, 11(1): 33-47.
Spielberger, C. D. (1985). Assessment of state and trait anxiety: Conceptual and methodological issues. The Southern Psychologist, 2: 6-16.
Racial prejudice measures
Quillian, L. (2006). New approaches to understanding racial prejudice and discrimination. Annual Review of Sociology, 32: 299-328.
Wittenbrink, B., Judd, C. M., & Park, B. (1997). Evidence for racial prejudice at the implicit level and its relationship with questionnaire measures. Journal of Personality and Social Psychology, 72(2): 262-274.