He has extensive experience directing empirical analyses utilizing primary and secondary data bases, and is acknowledged as a national expert on using administrative databases, particularly Medicare and health insurer data, for health policy research.He has served as a consultant to several of the largest health care organizations including: UnitedHealth Group, Blue Cross Blue Shield, Johnson and Johnson, Medtronic, Pfizer, Merck, Johns Hopkins Hospital, and various government agencies. He is currently the principal investigator for several projects evaluating the impact of consumer-directed health plans.