[1] Lund Univ, Skane Univ Hosp, Dept Dermatol & Venereol, SE-20502 Malmo, Sweden
[2] Hosp Innlandet Trust, Norwegian Natl Advisory Unit Concurrent Subst Abu, Brumundal, Norway
[3] Oslo Univ Hosp, Dept Dermatol, Oslo, Norway
[4] Justus Liebig Univ, Dept Dermatol, Giessen, Germany
[5] Rumailah Hosp, Hamad Med Corp Doha, Dept Dermatol, Doha, Qatar
[6] Justus Liebig Univ, Inst Med Psychol, Giessen, Germany
[7] Univ Zaragoza, Dept Psychol, Zaragoza, Spain
[8] Univ Libre Bruxelles, Dept Dermatol, Brussels, Belgium
[9] Zealand Univ Hosp, Dept Dermatol, Roskilde, Denmark
[10] Univ Copenhagen, Hlth Sci Fac, Copenhagen, Denmark
[11] Univ Hosp Brest, Dept Dermatol, Brest, France
[12] Univ Szeged, Dept Dermatol & Allergol, Szeged, Hungary
[13] Ben Gurion Univ Negev, Beer Sheva, Israel
[14] IRCCS, IDI, Clin Epidemiol Unit, Rome, Italy
[15] Radbout Univ, Med Ctr, Dept Med Psychol, Radbout Inst Hlth Sci, Nijmegen, Netherlands
[16] Stavanger Univ Hosp, Dept Dermatol, Stavanger, Norway
[17] Wroclaw Med Univ, Dept Dermatol, Wroclaw, Poland
[18] Moscow Sci & Pract Ctr Dermatovenereol & Cosmetol, Moscow, Russia
[19] Royo Villanova Hosp, Dept Dermatol, Zaragoza, Spain
[20] Univ Hlth Sci, Istanbul Sisli Hamidiye Etfal Training & Res Hosp, Dept Dermatol & Venereol, Istanbul, Turkey
[21] Cardiff Univ, Sch Med, Dept Dermatol, Cardiff, Wales
[22] Univ Hertfordshire, Sch Life & Med Sci, Inst Med Dev, Hatfield, Herts, England