1. Center for Health Outcomes and Policy Research, School of Nursing, University of Pennsylvania, 418 Curie Boulevard, Philadelphia, PA 19204-4217, USA
2. Leonard Davis Institute of Health Economics, University of Pennsylvania, 3641 Locust Walk, Philadelphia, PA 19104-6218, USA
3. Robert Wood Johnson Foundation Nurse Faculty Scholars Program, RWJF, P.O. Box 2316, Route 2 and College Road East, Princeton, NJ 08543, USA
4. Center for Mental Health Policy, School of Medicine, Department of Psychiatry, University of Pennsylvania, 3535 Market Street 3rd Floor, Philadelphia, PA 19104-2648, USA