[1] Univ Agder, Fac Hlth & Sport Sci, Dept Hlth & Nursing Sci, Kristiansand, Vest Agder, Norway
[2] UCL, Marie Curie Palliat Care Res Dept, Div Psychiat, London, England
[3] Sorlandet Hosp, Dept Clin Res, Kristiansand, Vest Agder, Norway
[4] Univ Agder, Fac Hlth & Sport Sci, Dept Hlth & Nursing Sci, Postboks 422, N-4604 Kristiansand, Vest Agder, Norway