Maria is a Quantitative Psychologist, Psychometric Consultant, and Senior Behavioral Scientist at the RAND Corporation. She has extensive knowledge of test theory including Item Response Theory (IRT) and of advanced multivariate analysis methods such as Structural Equation Modeling (SEM) and latent growth mixture modeling. Dr. Edelen is currently PI of the PROMIS Smoking Initiative, a NIDA-funded project that utilizes modern measurement methods to develop item banks for assessing smoking behaviors and biopsychosocial correlates of smoking. Other ongoing research on instrument development and validation is supported by grants from the National Institute of Drug Abuse and the National Heart, Lung, and Blood Institute. These and completed measurement projects include work with expert panels and evaluation of extant measures in addition to development of new items and measures. Grants from NIH have also supported Dr. Edelen’s work examining trends in substance use over time through advanced analysis of longitudinal data, as well as mediation analysis of a school-based drug prevention program. Dr. Edelen has been working with Green Advantage on their testing program since 2010.