Do expectations determine postoperative disability in women with endometriosis? Study protocol for a clinical mixed-methods observational cohort study

INTRODUCTION: Overall, 20%–30% of women with endometriosis report endometriosis-related disability after successful laparoscopy. This indicates a potential impact of psychological factors, such as expectations, on treatment outcomes. It is already known that expectations determine treatment outcomes in various health conditions, such as cardiologic or gynaecology. Therefore, we investigate the impact of expectations and other psychological factors on patients’ course of treatment outcomes after laparoscopy. METHODS AND ANALYSIS: A longitudinal mixed-methods study with N=300 women treated at a specialised centre of surgical endoscopy and endometriosis will be conducted with one preoperative and eight postoperative assessments of endometriosis-related disability and a priori specified predictors such as expectations. Additionally, two subsamples (each ~n=30) will be either interviewed about their endometriosis-related disability, expectations, and experiences of laparoscopy before and after surgery or asked once per day for 30 consecutive days using ambulatory assessments. Quantitative data will be analysed using multilevel modelling for longitudinal data. Structural content analysis will be used for qualitative data. DISCUSSION: To optimise treatment for women with endometriosis, it is essential to understand how treatment expectations and other psychological and medical factors influence treatment outcomes after laparoscopy. ETHICS AND DISSEMINATION: The Ethics Committee of the Psychotherapeutenkammer Hamburg, Germany, gave ethical approval (ROXWELL-2021-HH, 25 June 2021). TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT05019612).