1. Department of Psychiatry, University of Groningen, University Medical Center of Groningen, Groningen, The Netherlands
2. Department of Primary and Community Care, Radboud University Medical Center, Nijmegen, The Netherlands
3. Nivel, Netherlands Institute of Health Services Research, Utrecht, The Netherlands
4. Tilburg School of Social and Behavioral Sciences, Tranzo Scientific Center for Care and Welfare, Tilburg University, Tilburg, The Netherlands