The diagnosis and classification of diabetes mellitus in nonpregnant adults.

This article reviews the definition, diagnosis, and classification of diabetes and focuses on the rationale for and the limitations of the new diagnostic criteria for diabetes adopted by the American Diabetes Association in 1997. It also reviews the impact of the new fasting criterion for diabetes on both the prevalence of diabetes and the phenotype of individuals identified. Finally, it describes the revised classification scheme for diabetes and explains how it simplifies and clarifies some of the confusion created by the previous scheme.