Validation of the Revised Brief Diabetes Knowledge Test (DKT2)

Abstract

Purpose The purpose of this study is to examine the reliability and validity of the revised Diabetes Knowledge Test (DKT2). The original test was updated to reflect current diabetes care and education guidelines. The test has 2 components: a 14-item general test and a 9-item insulin use subscale. Methods Two samples were used to evaluate the DKT2. The first came from an online survey company (Qualtrics, LCC) (n = 101) and the second from University of Michigan’s (UofM) Diabetes Registry (n = 89). Cronbach’s coefficient alpha was used to calculate reliability. To examine validity, comparisons by type of diabetes, insulin use and oral medication use, and educational level were completed. Correlations between diabetes duration and both the general test and insulin subscale were calculated for the UofM sample. Results The two samples differed demographically. While the reliabilities between the samples were disparate, when combined, the coefficient alphas demonstrated reliability for both the general test (.77) and the insulin use subscale (.84). The validation comparisons proved to be similar; different results occurred between samples but when combined demonstrated validity. Conclusions The reliability and validity tests were inconsistent by sample. The different results can, in part, be attributed to the demographic differences between the 2 samples. With the exception of age, the samples differed in every other measured variable. However, when the samples were combined, the analyses supported the reliability and validity of the Diabetes Knowledge Test 2. The DKT2 is a quick and low-cost method of assessing general knowledge of diabetes and diabetes self-care.