Reliability and validity of a diabetes quality-of-life measure for the diabetes control and complications trial (DCCT). The DCCT Research Group.

We have developed a diabetes quality-of-life (DQOL) measure oriented toward the patient with insulin-dependent diabetes mellitus (IDDM). The DQOL was assessed for its reliability and validity in a group of patients with IDDM (n = 192). We found that the DQOL and its four scales had high degrees of internal consistency (Cronbach's r = .66-.92) and excellent test-retest reliability (r = .78-.92). Using conceptually relevant measures of psychiatric symptoms, perceived well-being and adjustment to illness, we also demonstrated convergent validity of the DQOL. This instrument was initially designed for use in the Diabetes Control and Complications Trial, a multicenter controlled clinical trial evaluating the effects of two different diabetes treatment regimens on the appearance and progression of early vascular complications. However, the DQOL may also be useful in evaluating the quality of life in other groups of patients with IDDM.