1. Siri Néss, Institute of Applied Social Research, Oslo, Correspondence Address: Siri Néss Institute of Applied Social Research Munthes gt. 31 0260 Oslo Norvay
2. National Institute for Public Health, Community Medicine Research Unit, Verdal
3. Dept. of Behavioural Sciences in Medicine, University of Oslo
4. Psychiatric Clinic VIA, Ullevaal Hospital, Oslo
5. National Institute for Public Health, Oslo, Norway