The reliability and validity of the Danish Draft Board Cognitive Ability Test: Børge Prien’s Prøve

The Danish Draft Board has used the same test for assessing general cognitive ability, the Børge Prien's Prøve (BPP), for over 50 years during which time all men on reaching the age of 18 become liable for conscription. Data from the test has, over the decades, been used in numerous and wide-ranging research studies. Nonetheless, owing to the special circumstances of its administration, some psychometric properties, which are generally assessed for psychological tests, have not previously been investigated for the BPP. First, since the test is only used at the assessment phase, retesting with the BPP occurs only rarely and under exceptional circumstances. Therefore, its Test-Retest reliability has hitherto not been documented. Second, questions have often been raised as to whether the validity of the BPP is undermined by either a lack of motivation and under-performing among some of the men taking the test, being, as they are, compelled to do so, and/or by gradual obsolescence of the test over the decades of its use. We here present findings from three new studies to show that (a) the BPP has a satisfactory Test-Retest reliability, r=0.77, (b) BPP test scores are not positively associated with expressed attitude to being called upon to serve conscription and (c) the correlation between the BPP and a measure of educational level has remained stable (at about 0.5) through the last two decades. Taken together these three findings further support the continuing value of the BPP in research relating to cognitive ability.