Quality of life and prevalence of arthritis reported by 5.795 members of the Nordic Psoriasis Associations. Data from the Nordic Quality of Life Study. - Zachariae,H.; Zachariae,R.; Blomqvist,K.; Davidsson,S.; Molin,L.; Mork,C.; Sigurgeirsson,B. (Acta Derm Venereol, 2002)