[1] Univ Hosp Munster, Dept Dermatol, Competence Ctr Chron Pruritus, Munster, Germany
[2] Univ Hosp Hamburg Eppendorf, Competence Ctr Healthcare Res Dermatol CVderm, Inst Healthcare Res Dermatol & Nursing IVDP, Hamburg, Germany
[3] Moscow Sci & Pract Ctr Dermatovenerol & Cosmetol, Moscow, Russia
[4] Lund Univ, Skane Univ Hosp, Dept Dermatol & Venereol, Malmo, Sweden
[5] Univ Hosp Gentofte, Dept Dermatol, Copenhagen, Denmark
[6] Univ Cattolica Sacro Cuore, Inst Dermatol, Rome, Italy
[7] Justus Liebig Univ, Giessen, Germany
[8] Univ Coimbra, Univ Hosp, Dept Dermatol, Coimbra, Portugal
[9] Univ Coimbra, Fac Med, Coimbra, Portugal
[10] Univ Oslo, Oslo Univ Hosp, Dept Dermatol, Oslo, Norway
[11] Royal Free Hosp, Dept Dermatol, London, England
[12] Charite Univ Med Berlin, Dept Dermatol & Allergy, Berlin, Germany
[13] Univ Rzeszow, Dept Dermatol, Rzeszow, Poland
[14] Adnan Menderes Univ, Dept Dermatol, Aydin, Turkey
[15] Munster Univ Hosp, Dept Psychosomat & Psychotherapy, Munster, Germany
[16] Univ Autonoma Barcelona, Hosp St Pau, Dept Dermatol, Cutaneous Allergy Unit, Barcelona, Spain
[17] Klinikum Dortmund GmbH, Dept Dermatol, Dortmund, Germany
[18] Kantonsspital Aarau, Dept Dermatol, Aarau, Switzerland
[19] Lund Univ, Skane Univ Hosp SUS Lund, Dept Dermatol & Venereol, Lund, Sweden
[20] Ludwig Maximilians Univ Munchen, Dept Dermatol & Allergol, Munich, Germany
[21] Univ Munster, Inst Med Informat, Munster, Germany
[22] Heidelberg Univ, Dept Social Med Occupat & Environm Dermatol, Heidelberg, Germany
[23] Wroclaw Med Univ, Dept Dermatol Venereol & Allergol, Wroclaw, Poland
[24] Med Univ Graz, Dept Dermatol, Graz, Austria