Abstract
This paper investigates levels in diabetes prevalence patterns across key socioeconomic status indicators and how they changed over time. The investigation spans both the conventional concept of diagnosed diabetes and a more comprehensive measure that includes those whose diabetes is undiagnosed. By doing so, I separate the distinct impact of covariates on trends over time in disease onset and the probability of disease diagnosis. The principal force leading to higher diabetes prevalence over time is excessive weight and obesity, which was only partially offset by improvements in the education of the population over time. Undiagnosed diabetes remains an important health problem, but much less so than 25 years ago. Although race and ethnic differentials in undiagnosed diabetes were eliminated over the last 25 years, the disparities became larger across other measures of disadvantage, such as education.