Can we rely on retrospective pain assessments?

The objective of this paper was to study whether subjects in a workplace setting are able to assess the intensity of musculoskeletal pain retrospectively for a period of 3 months. The intensity of average pain and maximum pain in eight anatomic regions was assessed on a numeric rating scale. The results of 12 consecutive weekly pain recordings were compared with a final retrospective assessment of pain intensity covering the same 3-month period (119 subjects). The degree of agreement was good or excellent. The subjects were able to distinguish between the worst complaints and average complaints, and the subjective perception of aggravations or improvements corresponded to the direction of a change in score. Current complaint status slightly influenced the memory of pain. The reproducibility of the questionnaire was also assessed and showed kappa coefficients between 0.44 and 0.91 (36 subjects). The results suggest that subjects are able to accurately recall and rate the severity of pain or discomfort for a period of 3 months. These findings are of practical importance in epidemiologic studies, because they imply that retrospective reports on pain intensity are sufficiently reliable.