1. From the Department of Public Health and Primary Care, KU Leuven, Leuven, Belgium (Drs Delvaux, Heselmans, Ramaekers, and Aertgeerts);
2. the Department of Public Health, Vrije University Brussels, Brussels, Belgium (Dr Van Thienen);
3. the GUIDES project, Norwegian Institute of Public Health, Oslo, Norway (Dr Van de Velde);
4. and the Centre for Evidence-Based Medicine (CEBAM), Belgian Branch of the Dutch Cochrane Collaboration, Leuven, Belgium (Drs Ramaekers and Aertgeerts).