He has expertise in psychometrics, the analysis of change, and mixture modeling with alcohol and addiction data. Dr. Flaherty conducts both methodological and substantive research. Recent statistical and methodological research includes working with a parameterization of the latent class model referred to as associative latent transition analysis, as well as issues around measurement invariance in the latent class context. Dr. Flaherty’s substantive research focuses on substance use onset and dependence, including research on transitions in tobacco use among adult smokers in association with measures of AOD use, and patterns of alcohol and substance use in national data.