Face Validity [1]
Face validity, as the name suggests, is a measure of how representative a research project is 'at face value,' and whether it appears to be a good project.
It is built upon the principle of reading through the plans and assessing the viability of the research [3], with little objective measurement [4].
Whilst face validity, sometime referred to as representation validity, is a weak measure of validity, its importance cannot be underestimated.
This 'common sense' approach often saves a lot of time, resources and stress.
Face Validity - Some Examples
In many ways, face validity [5] offers a contrast to content validity [6], which attempts to measure how accurately an experiment [7] represents what it is trying to measure.
The difference is that content validity is carefully evaluated, whereas face validity is a more general measure and the subjects often have input.
An example could be, after a group of students sat a test, you asked for feedback, specifically if they thought that the test was a good one. This enables refinements for the next research project and adds another dimension to establishing validity [8].
Face validity is classed as 'weak evidence' supporting construct validity [9], but that does not mean that it is incorrect, only that caution is necessary.
For example, imagine a research paper [10] about Global Warming. A layperson could read through it and think that it was a solid experiment [11], highlighting the processes behind Global Warming.
On the other hand, a distinguished climatology professor could read through it and find the paper, and the reasoning [12] behind the techniques, to be very poor.
This example shows the importance of face validity as useful filter for eliminating shoddy research from the field of science, through peer review [13].
If Face Validity is so Weak, Why is it Used?
Especially in the social and educational sciences, it is very difficult to measure the content validity of a research program.
Often, there are so many interlinked factors that it is practically impossible to account for them all. Many researchers send their plans to a group of leading experts in the field, asking them if they think that it is a good and representative program.
This face validity should be good enough to withstand scrutiny and helps a researcher to find potential flaws before they waste a lot of time and money.
In the social sciences, it is very difficult to apply the scientific method [14], so experience and judgment are valued assets.
Before any physical scientists think that this has nothing to do with their more quantifiable approach [15], face validity is something that pretty much every scientist uses.
Every time you conduct a literature review [16], and sift through past research papers [10], you apply the principle of face validity.
Although you might look at who wrote the paper, where the journal [17] was from and who funded [18] it, ultimately, you ask 'Does this paper do what it sets out to?'
This is face validity in action.
Bibliography
Babbie, E.R. (2007). The Practice of Social Research. Belmont, CA: Wadsworth Cengage Learning
Gatewood, R.D., Feild, H.S., & Barrick, M. (2008). Human Resource Selection (6th Ed.). Mason, OH: Thomson
Polit, D.E., & Tatano Beck, C. (2008). Nursing Research : Generating and Assessing Evidence for Nursing Practice (8th Ed.). Philadelphia, PA: Lippincott Williams & Watkins