Comparison of the psychometric properties of four dementia knowledge measures: Which test should be used with dementia care staff?

Abstract

To compare the psychometric properties of four measures of dementia institutional knowledge. Fifty-eight dementia care staff completed the Dementia Knowledge Assessment Tool Version Two (DKAT2), Alzheimer's Disease Knowledge Test (ADKT), Alzheimer's Disease Knowledge Scale (ADKS) and Dementia Knowledge Twenty (DK-20). The convergent validity and reliability of each measure were examined. The level of dementia knowledge in this sample was similar to that reported in comparable surveys. The ADKT, DKAT-2 and DK-20 had marginal to acceptable internal consistency (α ≥ 0.67), and the ADKT, DK-20 and ADKS were positively correlated with each other (r's = 0.45-0.60), demonstrating convergent validity. The DKAT2 had lower intercorrelations with the other measures (r's = 0.32-0.45). The ADKS had poor internal consistency (α = 0.29). As the first head-to-head comparison of these tests in a single sample, this study should assist clinicians and researchers to select a dementia knowledge test.