Does interdisciplinary group care for the treatment of endometriosis improve pain interference: protocol for a pilot randomised controlled trial at an urban academic medical centre.

Introduction: Endometriosis affects 10-15% of people assigned female at birth and can cause chronic pelvic pain and impair many domains of quality of life, such as fertility, mood and bladder, bowel and sexual function. Current treatments often fail, leading to recurrent pain and the need for reintervention. As endometriosis negatively affects many domains of life, a variety of non-pharmacological treatments modestly improve symptoms. To bundle these interventions into accessible packaging, our interdisciplinary team developed a novel endometriosis intervention titled 'Peer-Empowered Endometriosis Pain Support (PEEPS)', an 8-week integrative group care intervention. Here, we present the protocol for a pilot randomised controlled trial (RCT) to evaluate the effectiveness and implementation of PEEPS for people with endometriosis-associated pain refractory to surgical management. We hypothesise that patients who complete the PEEPS programme will show a greater decrease in pain interference in daily activities at intervention completion as compared with baseline than those in the education arm.

Methods And Analysis: This is a hybrid type 1 effectiveness-implementation mixed-methods RCT in which 60 participants will be randomised using computer-generated random numbers stratified by group in the ratio 1:1 to PEEPS plus usual versus educational handout plus usual care. The primary outcome is change in pain interference from baseline to intervention completion. Secondary outcomes include change in pain interference from baseline to 6 months and 12 months postintervention, as well as change in other quality-of-life measures as measured by nine validated questionnaires from baseline to completion, 6 months and 12 months. Proctor 's will be used to evaluate acceptability, appropriateness and feasibility of PEEPS implementation, and the Consolidated Framework for Implementation Research will be used to guide the evaluation of barriers and facilitators of PEEPS at the patient and provider levels. Primary data analyses will follow the intention-to-treat principle. Descriptive statistics and two-sample t-tests for normally distributed values and Wilcoxon Rank-Sum test were performed for non-normally distributed values. Frequency analysis and Fisher's exact or χ tests will be used for categoric variables as appropriate. Longitudinal analysis of the primary and secondary outcomes will be conducted with a mixed-effects model to investigate the effect of PEEPS compared with education. Least square means (LSMs) and the corresponding 95% CIs at each timepoint, as well as LSM differences and 95% CIs between any post-baseline and baseline will be provided for the outcomes. ORs and 95% CIs will be calculated for categorical outcomes. Qualitative data will be collected in the form of open-ended feedback, focus groups with programme completers and semistructured interviews with participants who complete two or fewer sessions. The analysis will use an embedded design-experimental model in which quantitative and qualitative outcomes will occur concurrently with weight priority given to quantitative data.

Ethics And Dissemination: This trial was approved by the Washington University in St. Louis Institutional Review Board (protocol 202402082) on 27 March 2024 and has low risk of harm to participants. All deidentified data from this project will be shared via Digital Commons@Becker. The findings of this study will be disseminated via scientific meetings and peer-reviewed journals. The results and conclusions will be summarised for patients and the public in common language using infographics to make the findings accessible. This pilot RCT will yield the effect size for PEEPS and generate implementation context and outcomes data to guide PEEPS application to real-world practice. If PEEPS proves to be effective, this study will inform adaptation and scaling to improve the lives of people with endometriosis through a non-hormonal, fertility-preserving approach.

Trial Registration Number: ClinicalTrials.gov; NCT06549985.