Assessing the Quality of Randomized Controlled Trials of Complex Regional Pain Syndrome Published in the Journal of Clinical Pain Medicine Field

Abstract Background: Complex regional pain syndrome is a disease characterized by chronic pain caused by tissue damage and worsens over time. The quality of randomized controlled trials on complex regional pain syndrome is low due to the rarity of the disease and difficulty in designing studies. Therefore, we evaluated the completeness of evidence by assessing the quality. Methods: We searched articles that were published between 1998 and 2017. The quality was assessed using the Jadad scale, van Tulder scale, and the Cochrane collaboration risk of bias tool.Results: A total of 72 articles on complex regional pain syndrome have been published. Only 31 articles were found to have a low risk of bias according to the Cochrane Collaboration. On the Jadad and van Tulder scale, 52 and 58 articles, respectively, were assessed as high quality. Only a few trials described the randomization method adequately and presented allocation concealment correctly. We also found that research trials with funding statements had higher Jadad scales than unfunded (P = 0.03). Furthermore, articles that described the sample size were of significantly higher quality (P < 0.01) than those that did not. Conclusions: There was no observed improvement in quality over time. In particular, the performance rate of the allocation concealment for the analyzed papers was low. In addition, we found that the number of high-quality articles increased when institutional review board approval was granted and funding provided. For the future, we recommend that researchers focus their efforts on conducting high-quality studies.