1. Karolinska Institute, Department of Social Medicine, Kronan Health Centre, S-172 83 Sundbyberg, Sweden, Dr Marlene Stenbacka Dept. of Social Medicine Kronan Health Centre S-17283 Sundbyberg
2. Peter Allebeck, Department of Community Medicine, Huddinge University Hospital, S-141 86 Huddinge, Sweden
3. Lena Brandt, Department of Community Medicine, Huddinge University Hospital, S-141 86 Huddinge, Sweden
4. Anders Romelsjö, Karolinska Institute, Department of Social Medicine, Kronan Health Centre, S-172 83 Sundbyberg, Sweden.