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 received
an oral glucose tolerance test. The Second National Health and Nutrition Examination Survey,
1976–1980, and Hispanic HANES used similar procedures 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.