The aim of this study was to find out which aspects of health-related quality of life (HRQL), measured with generic instruments, are important to patients with reflex sympathetic dystrophy (RSD) affecting the arm or leg. The Sickness Impact Profile 68 (SIP68), the Nottingham Health Profile (NHP), and the EuroQol-5D (EQ-5D) were completed by 54 patients suffering from RSD (33 arm, 21 leg). The scores of the three questionnaires for patients with an affected arm or leg are presented. Aspects relevant to patients with RSD of the arm include the NHP1 dimensions of pain (mean score: 63%), sleep (58%), and energy (45%), and the EQ-5D dimensions of pain (67% extreme), usual activities (76% some problems), and self care (76% some problems). Aspects relevant to patients with RSD of the leg include the SIP68 dimensions of social behavior (51%) and mobility control (46%), the NHP 1 dimensions of pain (mean score: 86%), mobility (54%), energy (53%), and sleep (52%), and the EQ-5D dimensions of mobility (81% some problems), pain (71% extreme), and usual activities (71% some problems). The study showed that applying generic HRQL instruments and measuring treatment effect with the dimensions scoring high provides a responsive instrument which at the same time gains information concerning dimensions not maximally responsive to a specific disease. Some dimensions which, on the basis of their label, might be expected to be important were found not to be so. After using this approach, clinicians can more directly focus treatment on specific areas that have been shown to affect a patient's HRQL. (C) U.S. Cancer Pain Relief Committee, 2000.