Sensitivity and specificity of death certificates for diabetes: as good as it gets?

OBJECTIVE Diabetes is the sixth leading cause of death in U.S adults, which may be an underestimate because of under-reporting on death certificates. In this study we examined death certificate sensitivity and specificity for diabetes, as well as the factors related to better reporting, in a community-based sample. RESEARCH DESIGN AND METHODS Death certificates were obtained for 3,209 decedents who were enrolled in the Rancho Bernardo cohort in 1972-1974 and followed through 2003. Diabetes status was reassessed at periodic clinic visits and annual mailed surveys during an average follow-up of 15.2 +/- 7.6 years. Diabetes reported anywhere on death certificates was abstracted. Sensitivity and specificity calculations among diabetic participants were stratified by age, sex, year, place, cause of death, and diabetes medication use. RESULTS Among 1,641 men and 1,568 women, 378 decedents had a history of diabetes, 168 of whom had diabetes listed anywhere on their death certificates. The sensitivity and specificity were 34.7 and 98.1%. Diabetes reporting on death certificates did not improve over time or vary significantly by age and sex, but sensitivity for diabetes reporting was better for recent (1992-2003) cardiovascular disease (CVD) deaths compared with any other causes of death (48.9 vs. 28.6%, respectively, P < 0.05). CONCLUSIONS Although diabetes reporting on death certificates did not improve over time, sensitivity was better for diabetes in the context of CVD deaths, probably reflecting the increasing recognition that diabetes is a major cardiovascular risk factor.