The reporting of adverse events following spinal manipulation in randomized clinical trials-a systematic review

Background context Spinal manipulative therapy (SMT) is commonly used to treat spinal disorders. Although clinical practice guidelines recommend the use of SMT in the treatment of neck and back disorders, concerns exist about the nature and incidence of adverse events associated with the intervention. Comprehensive reporting of adverse events in clinical trials could allow for accurate incidence estimates through meta-analysis. However, it is not clear if randomized clinical trials (RCTs) that involve SMT are currently reporting adverse events adequately. Purpose This study aimed to describe the extent of adverse events reporting in published RCTs involving SMT, and to determine whether the quality of reporting has improved since publication of the 2010 Consolidated Standards Of Reporting Trials (CONSORT) statement. Study design This is a systematic literature review. Methods The Physiotherapy Evidence Database (PEDro) and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched for RCTs involving SMT. Domains of interest included classifications of adverse events, completeness of adverse events reporting, nomenclature used to describe the events, methodological quality of the study, and details of the publishing journal. Data were analyzed using descriptive statistics. Frequencies and proportions of trials reporting on each of the specified domains above were calculated. Differences in proportions between pre- and post-CONSORT trials were calculated with 95% confidence intervals using standard methods, and statistical comparisons were analyzed using tests for equality of proportions with continuity correction. There was no funding obtained for this study. The authors declare no conflict of interest. Results Of 7,398 records identified in the electronic searches, 368 articles were eligible for inclusion in this review. Adverse events were reported in 140 (38.0%) articles. There was a significant increase in the reporting of adverse events post-CONSORT (p=.001). There were two major adverse events reported (0.3%). Only 22 articles (15.7%) reported on adverse events in the abstract. There were no differences in reporting of adverse events post-CONSORT for any of the chosen parameters. Conclusions Although there has been an increase in reporting adverse events since the introduction of the 2010 CONSORT guidelines, the current level should be seen as inadequate and unacceptable. We recommend that authors adhere to the CONSORT statement when reporting adverse events associated with RCTs that involve SMT.