[1] Univ Hosp Munster, Dept Dermatol, Ctr Chron Pruritus, Von Esmarch Str 58, D-48149 Munster, Germany
[2] Univ Med Ctr Hamburg Eppendorf, Inst Hlth Serv Res Dermatol & Nursing, Hamburg, Germany
[3] Univ Munster, Inst Med Informat, Munster, Germany
[4] Univ Hosp Moscow, Dept Dermatol, Moscow, Russia
[5] Univ Cattolica Sacro Cuore, Dept Dermatol, Fdn Policlin Univ Agostino Gemelli, Rome, Italy
[6] Med Univ Graz, Dept Dermatol, Graz, Austria
[7] Das Kurhause Bad Gleichenberg, Bad Gleichenberg, Austria
[8] Univ Hosp Brest, Dept Dermatol, Brest, France
[9] Wroclaw Med Univ, Dept Dermatol Venereol & Allergol, Wroclaw, Poland
[10] Univ Rzeszow, Dept Dermatol, Rzeszow, Poland
[11] Adnan Menderes Univ, Dept Dermatol, Aydin, Turkey
[12] Univ Autonoma Barcelona, Cutaneous Allergy Unit, Dept Dermatol, Hosp St Pau, Barcelona, Spain
[13] Kantonsspital Aarau, Dept Dermatol, Aarau, Switzerland