Most of the participants were Caucasian (55.8%), followed by African-American (33.7%). There were slightly more men (53.7%; mean age 35.3 years) than women (mean age 34.2 years) in the sample. This same sample was also used in a recent taxometric study of the latent structure of adult attention deficit/hyperactivity disorder (Marcus et al., 2012). Additional details about the demographic features, diagnostic assessment, and study procedures may be found in that report.
