Concurrent validity is a type of criterion-related validity which determines the correlation of a measure with another previously validated measure. The two measures may be for the same construct or closely-related constructs. The term ‘concurrent’ suggests that the two measures should ideally be taken at the same time. Practically, measures may have some time difference between them. However, if there is a considerable amount of time difference between the two measures, then the validity is called predictive-validity (another criterion-related validity).
The two measures, between which correlation is found, can be for the same construct but are most often used for related constructs. The predictive power of the test is analysed using correlation or linear regression.
One weakness of concurrent validity is that a high correlation between two measures need not necessarily mean that the test is valid. One of the measures might be flawed and if the other measure shows a high correlation with the previous, it would mean that both measures are flawed and the test is invalid.
An employment test is administered to the workers and the scores are correlated with the ratings given by the immediate supervisor on the same day. The correlation between these scores would determine the concurrent validity between the two measures i.e. scores of the employment test and ratings given by the immediate supervisor.
Concurrent validity can be used to check the validity of a newly designed scholarship test which tests a student’s mathematical aptitude. Scores of this test can be compared with the scores received by students in the mathematics examinations designed by their schools (which are a recognized and reliable indicator of mathematical ability) and the accuracy of the scholarship test can be determined. The key is that the scholarship test should be held within a week before or after the school examinations.