Outcome reporting in trials on conservative interventions for pelvic organ prolapse: A systematic review for the development of a core outcome set

Background: Significant risk of bias and limitations in outcome selections in trials evaluating conservative treatments for the management of Pelvic Organ Prolapse (POP) have been highlighted and preclude comparability of outcomes, synthesis of primary studies and high quality evidence. Objectives: As systematic review of the reported outcomes is the first step in the process of development of a Core Outcome Set (COS), we aimed to systematically review reporting of outcomes and outcome measures in Randomised Control Trials (RCTs) on conservative treatments for POP and develop an inventory of them for consideration as core outcome and outcome measures sets. We evaluated methodological quality, outcome reporting quality and publication characteristics and their associations among published RCTs. Study design: Systematic review of RCTs identified from the following databases: Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE and MEDLINE (Pubmed). RCTs evaluating the effectiveness of conservative interventions for the management of POP were considered for inclusion. Outcomes and outcome measures were obtained from the RCTs and an inventory was created. Outcomes were grouped in domains and themes. Methodological quality, outcome reporting quality and publication characteristics were evaluated and statistically analysed. Results: Twenty-five trials (3179 women) were included and reported 31 outcomes and 50 outcome measures. Reporting rates of the outcomes investigated ranged between 4% and 56%. The most commonly reported outcome domains were patient reported symptoms, stage of POP expressed as POP-Q stage, and quality of life. Univariate analysis demonstrated no significant correlations of methodological and outcome reporting parameters. Conclusions: There is a need to increase comparability of RCTs. Reporting standardized outcomes included in a COS for conservative interventions for POP will facilitate the comparability across RCTs. While the process of developing COS is in progress, we propose the interim use of the three most commonly reported outcomes in each domain: patient-reported outcomes (symptom distress including bowel and urinary symptoms, sexual function), stage of prolapse and quality of life parameters using validated questionnaires (Pelvic Floor Distress Inventory 20 (PFDI-20), Pelvic Floor Impact Questionnaire/Health related quality of life (PFIQ-7/HRQOL) and Pelvic Organ Prolapse Impact Questionnaire (POPIQ-7). Keywords: Conservative management; Core outcome measures sets (COMS); Core outcome sets (COS); Outcome measures; Outcomes; Patient reported outcome measures symptoms (PROMs); Pelvic Floor Disorders; Pelvic Organ Prolapse