Validation of the Assessment
For example: a vendor may say that in a national survey conducted on salespeople and earned commissions, that there is at best a weak correlation between profile scores and commissions earned. Scores obtained on a national level would be unsatisfactory predictors of commissions earned.”
What assessment users should know is that it is important to know that sales commissions are consistently the number one indicator of sales performance, and if and when a vendor openly admits that their test scores are an unsatisfactory predictor on a national level and you may want to ask yourself why you would want to use this assessment.
Theory of the Test
Start with one simple question. Were the procedures used in validation consistent with generally accepted professional standards such as those described in the “Standards for Educational and Psychological Tests?” A reputable test publisher will generally make such a statement somewhere in its brochures or validity manuals.
Be cautious of any personality test that claims to have been written by a professional, and then immediately tries to lead you to the conclusion that it was professionally developed without referencing any validation or reliability studies. The two concepts do not necessarily go hand in hand.
What I would have to really question in relation to such a test would be whether or not the validity studies would meet the requirements of the “Uniform Guidelines on Employee Selection Procedures” as they pertain to the professional standards for validity studies.
Let’s say that a company has designed a test that measures communication styles and that the personality assessment is very effective. The validation studies for any assessment instrument are only an objective measure that evidences that the test actually measures what it purports to measure, and in this particular case it is communication styles.
Let’s say that this particular personality test is later given certain external modifications so that it can also be sold as a pre-employment assessment. The personality test is still backed by validity studies, but unless new validity studies are done, there are no validity studies to support the use of the assessment for its intended purpose as a pre-employment assessment. In this example, the intended use is quite clear (to measure communication styles).
The Uniform Guidelines on Employee Selection Procedures specifically state that the evidence of validity and utility of the selection procedure must support its operational use.
Cutting Through the Quagmire
Suppose we accept that 1) Causation is the only way to accurately predict performance and, 2) our Test Content is a pre-cursor to job performance. Our next question is how to prove or validate the test and arrive at good cut-off points. This takes a thorough knowledge of statistics and experimental design.
For example, we have to define what to predict. We have to find “hard” data that is hard to fake, something we know we can trust.
Okay, let’s suppose we have the right kind of hard data. What’s next? We need to compare test scores with on-the-job performance. We can do this several ways:
1. By giving the test to everyone who applies, hiring them all, waiting until we get performance data and comparing test scores with job performance.
2. By giving the test to people already in the job and comparing test scores with job performance.
Of course we’ll need to correct for “restriction of range,” that is, the people who are IN the job will be more similar than people who APPLY for the job. So what? Well, for one thing, we might not see the same kind of big differences between high and low producers that we would see between applicants.
Flawed decision-making in hiring leads to misguided job standards, using tests that are not validated properly, hiring the wrong people, and rejecting the right ones. It is a major reason why Congress passed the Civil Rights Act and the Department of Labor wrote the 1978 Uniform Guidelines on Employee Selection Procedures.