The reliability and validity of a brief diabetes knowledge test

To examine the reliability and validity of a brief diabetes knowledge test. The diabetes knowledge test has two components: a 14-item general test and a 9-item insulin-use subscale.

Two populations completed the test. In one population, patients received diabetes care in their community from a variety of providers, while the other population received care from local health departments. Cronbach's coefficient alpha was used to calculate scale reliability for each sample. To determine validity, patient group differences were examined. It was hypothesized that test scores would be higher for patients with type 1 diabetes, for patients with more education, and for patients who had received diabetes education.

The coefficient alpha s for the general test and the insulin-use subscale indicate that both are reliable, alpha > or = 0.70. In the community sample, patients with type 1 diabetes scored higher than patients with type 2 diabetes on the general test and the insulin-use subscale. In the health department sample, patients with type 1 scored higher than patients with type 2 on the insulin-use subscale. For both samples, scores increased as the years of formal education completed increased, and patients who received diabetes education scored higher than patients who did not.

Although the samples differed demographically, the reliability and validity of the test were supported in both the community and the health department samples. This suggests that the test is appropriate for a variety of settings and patient populations.