RESEARCH DESIGN AND METHODS— NHANES III contained a probability sample
of 18,825 U.S. adults 20 years of age who were interviewed to ascertain a medical history of diagnosed diabetes, a subsample of 6,587 adults for whom fasting plasma glucose values
w e re obtained, and a subsample of 2,844 adults between 40 and 74 years of age who re c e i v e d
an oral glucose tolerance test. The Second National Health and Nutrition Examination Survey,
1976–1980, and Hispanic HANES used similar pro c e d u res to ascertain diabetes. Prevalence was
calculated using the 1997 American Diabetes Association fasting plasma glucose criteria and
the 1980–1985 World Health Organization (WHO) oral glucose tolerance test criteria.