[1] Univ Med Ctr Hamburg Eppendorf, Dept Psychosomat Med & Psychotherapy, Hamburg, Germany
[2] Schon Klin Hamburg Eilbek, Hamburg, Germany
[3] Univ Copenhagen, Dept Publ Hlth, DK-1168 Copenhagen, Denmark
[4] Charite Univ Med Berlin, Dept Psychosomat Med, Berlin, Germany
[5] Schon Klin Bad Bramstedt, Bad Bramstedt, Germany
[6] Schon Klin Roseneck, Roseneck, Germany
[7] Schon Klin Starnberger See, Starnberg, Germany
[8] Univ Leipzig, Dept Med Psychol & Med Sociol, D-04109 Leipzig, Germany
[9] Univ Massachusetts, Sch Med, Dept Quantitat Hlth Sci, Worcester, MA USA