In 56 patients with severe chronic pain, pain relief was evaluated by observation of changes in activities of daily life (ADL), drug intake, and patients' mood. The degree of pain relief was scored on the basis of these evaluations by a pain clinic physician, a nurse, and a member of the patient's family. The resulting score was termed "pain relief score by observers" (PRSO). Subjective pain relief was evaluated by the visual analogue scale (VAS). Although a significant correlation (rS=0.755,P<0.001) was demonstrated between the mean PRSO and VAS values, there was some dissociation between the two values in patients with underlying personal problems such as compensation lawsuits or job loss. The results suggest that an objective evaluation of pain relief is possible by PRSO alone without subjective assessment, and that PRSO can be used for patients with various types of pain. Combined assessment of pain relief by the VAS and PRSO methods may be useful to detect the influence of personal background factors in patients with chronic pain.