[1] Social Medicine and Public Health Science,
[2] Department of Health and Environment,undefined
[3] University of Linköping and Department of Social Medicine,undefined
[4] University of Gothenburg,undefined
[5] Sweden,undefined
[6] Social Medicine and Public Health Science,undefined
[7] Department of Health and Environment,undefined
[8] University of Linköping,undefined
[9] Sweden,undefined
[10] Department of Social Medicine,undefined
[11] Vasa Hospital,undefined
[12] SE–41133 Gothenburg,undefined
[13] Sweden,undefined
[14] Tel.: +46-31-617957,undefined
[15] Fax: +46-31-162847,undefined
[16] E-mail: annukka.savikko@socmed.gu.se,undefined