Concurrent Validity

Validity refers to the degree to which a measure accurately taps the specific construct that it claims to be tapping. Criterion-related validity is concerned with the relationship between individuals’ performance on two measures tapping the same construct. It typically is estimated by correlating scores on a new measure with scores from an accepted criterion measure. There are two forms of criterion-related validity: predictive validity and concurrent validity.

Concurrent validity focuses on the extent to which scores on a new measure are related to scores from a criterion measure administered at the same time, whereas predictive validity uses the scores from the new measure to predict performance on a criterion measure administered at a later time.

Examples of contexts in which concurrent validity is relevant include the following:

• Scores on a written first aid exam are highly correlated with scores assigned by raters during a hands-on measure in which examinees demonstrate first aid procedures.
• Scores on a depression inventory are used to classify individuals who are simultaneously diagnosed by a licensed psychologist.

The primary motives for developing a new measure designed to tap the same construct of interest as an established measure are cost and convenience. A new measure that is shorter or less expensive but leads users to draw the same conclusions as a longer, more costly measure is a highly desirable alternative. For example, to obtain the necessary information about examinee ability, decision makers might be able to administer a short written test to a large number of individuals at the same time instead of pricey, one-on-one performance evaluations that involve multiple ratings.

Before users make decisions based on scores from a new measure, they must have evidence that there is a close relationship between the scores of that measure and the performance on the criterion measure. This evidence can be obtained through a concurrent validation study. In a concurrent validation study, the new measure is administered to a sample of individuals that is representative of the group for which the measure will be used. An established criterion measure is administered to the sample at, or shortly after, the same time. The strength of the relationship between scores on the new measure and scores on the criterion measure indicates the degree of concurrent validity of the new measure.

The results of a concurrent validation study are typically evaluated in one of two ways, determined by the level of measurement of the scores from the two measures. When the scores on both the new measure and the criterion measure are continuous, the degree of concurrent validity is established via a correlation coefficient, usually the Pearson product-moment correlation coefficient. The correlation coefficient between the two sets of scores is also known as the validity coefficient. The validity coefficient can range from–1 to + 1; coefficients close to 1 in absolute value indicate high concurrent validity of the new measure.

In the example shown in Figure 1, the concurrent validity of the written exam is quite satisfactory [Page 210]because the scores on the written exam correlate highly with the scores assigned by the rater; individuals scoring well on the written measure were also rated as highly proficient and vice versa.

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