1. TM Asikainen, MD, is Physician, Department of Occupational Health, Satakunta Central Hospital, Pori, Finland. At the time of the study, Dr Asikainen was Researcher, The President Urho Kaleva Kekkonen Institute for Health Promotion Research (UKK Institute), Tampere, Finland
2. JH Suni, PT, PhD, is the Senior Researcher, Director of Research Department, UKK Institute
3. ME Pasanen, MSc, is Statistician, UKK Institute
4. P Oja, PhD, is former Director of Research Department, UKK Institute
5. MB Rinne, MSc, is Researcher, UKK Institute
6. SI Miilunpalo, MD, is Chief Physician, Kiipula Foundation, Rehabilitation Centre, Finland, and a docent, Tampere School of Public Health, University of Tampere, Finland
7. CHA Nygård, PhD, is Professor, Tampere School of Public Health, University of Tampere
8. IM Vuori, MD, PhD, is Professor Emeritus, University of Tampere, and former Director, UKK Institute