Treatment of reflex sympathetic dystrophy (CRPS type 1): A research synthesis of 21 randomized clinical trials

A blinded meta analysis teas performed on randomized clinical trials (RCT) on the medicinal treatment of reflex sympathetic dystrophy (complex regiona l pain. syndrome type I) to assess the methodological quality and quantify the analgesic effect of treatments by calculating individual and summary ef fect sizes. The internal validity of 21 RCTs was investigated and the quali ty weighted summary effect size was calculated using a fixed effect model ( Glass Delta). The methodological quality ranged from moderate to good (aver age 46%). Differences were found between the trials in inclusion/exclusion criteria, treatment methods, duration of treatments and trials, and measure ment instruments. Statistical analysis was possible for four subgroups; one evaluating the analgesic effects of sympathetic suppressors in general (n = 12), one subgroup concerning the analgesic effects of guanethidine (n = 6 ), one investigating the analgesic effect of intravenous regional sympathet ic blocks (n = 9), and one subgroup (n = 5) evaluating the analgesic effect of calcitonin. Except for the calcitonin subgroup (P = 0.002), the quality -weighted summary effect size of these subgroups were not significant. No s ignificant analgesic effect by sympathetic suppressing agents could be esta blished. Calcitonin seems to Provide effective pain relief in reflex sympat hetic dystrophy patients. The results of the present study show that weight ing methodological quality influences the magnitude of the effect sizes of specific treatment methods. Future studies should control for methodologica l quality. J Pain Symptom Manage 2001: 21:511-526 (C) U.S. Cancer Pain Reli ef Committee, 2001.