Concurrent validation assesses the validity of a test by administering it to employees already on the job and then correlating test scores with existing measures of each employee’s performance. The logic behind this strategy is that if the best performers cur- rently on the job perform better on the test than those who are currently struggling on the job, the test has validity. As in any discriminating test, the results are more powerful if you are able to show that you can discriminate between two groups that are very similar.
In predictive validity, we assess the operationalization's ability to predict something it should theoretically be able to predict. You might theorize that a measure of math ability should be able to predict how well a person will do in an accounting or finance profession. We could give our measure to experienced finance experts and see if there is a high correlation between scores on the measure and their salaries as finance professionals. A high correlation would provide evidence for predictive validity, it would show that our measure can correctly predict something that we theoretically think it should be able to predict. Predictive validation seeks to establish an empirical relationship between test scores taken prior to being hired and eventual performance on the job.
In addition to work samples, which attempt to re-create specific work scenarios, performance tests can also be designed to mirror very broad aspects of the job that may draw on fundamental competencies needed to perform a wide range of job tasks. For example, the Administrative Assistant position may require individuals to routinely find specific materials to answer various questions posed by upset or hostile customers. Rather than re-create a large number of scenarios to cover a wide array of situations, employers may design a single exercise to measure the general competencies in question. For example, an interactive role-play between the applicant and a well-trained actor that measures applicant's problem solving, communication, and interpersonal skills. Applicant scores on work sample tests are generated by trained assessors who observe the applicant's behavior and/or by measuring task outcomes or the degree of interpersonal skills demonstrated or the number of errors made in transcribing an internal memo.
I feel every situation is unique and the work samples and recreating work scenarios are not a test of real performance in a position.