1. Centre for Evidence-Based Intervention; University of Oxford; Oxford UK
2. Centre for Outcomes Research and Effectiveness; Research Department of Clinical, Educational & Health Psychology; University College London; London UK
3. Centre for Statistics in Medicine; University of Oxford; Oxford UK
4. Institute of Child Care Research; Queen's University Belfast; UK
5. Clinical Epidemiology Program; Ottawa Hospital Research Institute Centre for Practice-Changing Research (CPCR); The Ottawa Hospital - General Campus; Ottawa ON Canada