Discrepancies between registered protocol and final publication in exercise interventions for chronic low back pain: a meta-research study

BackgroundEvidence of selective reporting bias is common in randomized controlled trials (RCTs) of various medical fields, undermining their integrity and credibility. However, this has not yet been assessed in exercise for chronic low back pain (cLBP) RCTs. Therefore, we will aim to assess the prevalence of discrepancies between the registered protocol and final publication in this field and the characteristics of RCTs with and without such discrepancies. MethodsWe will start from the RCTs included in the 2021 Cochrane review (n=249) and identified in its update (n=172) to select all RCTs reporting a protocol registration. Standardized data collection form will be developed to record information from both registration and publication. We will then detect discrepancies for primary and secondary outcomes, outcomes measures, timepoints, number of arms and statistical analysis plans between the registered protocol and final publication. We will use descriptive statistics to assess the proportion of RCTs with and without a discrepancy as well as to compare their characteristics. Ethics and disseminationWe will offer insights and recommendations for future RCTs avoiding selective reporting that can reflect in subsequent inaccuracies in systematic reviews or guidelines for clinical practice. Results of this study will be shared through conference presentations and publication in a peer-reviewed journals.