Stepped-wedge randomised trial of laparoscopic ventral mesh rectopexy in adults with chronic constipation: study protocol for a randomized controlled trial

Abstract

Background: Laparoscopic ventral mesh rectopexy (LVMR) is an established treatment for external full-thickness rectal prolapse. However, its clinical efficacy in patients with internal prolapse is uncertain due to the lack of high-quality evidence.

Methods: An individual level, stepped-wedge randomised trial has been designed to allow observer-blinded data comparisons between patients awaiting LVMR with those who have undergone surgery. Adults with symptomatic internal rectal prolapse, unresponsive to prior conservative management, will be eligible to participate. They will be randomised to three arms with different delays before surgery (0, 12 and 24 weeks). Efficacy outcome data will be collected at equally stepped time points (12, 24, 36 and 48 weeks). The primary objective is to determine clinical efficacy of LVMR compared to controls with reduction in the Patient Assessment of Constipation Quality of Life (PAC-QOL) at 24 weeks serving as the primary outcome. Secondary objectives are to determine: (1) the clinical effectiveness of LVMR to 48 weeks to a maximum of 72 weeks; (2) pre-operative determinants of outcome; (3) relevant health economics for LVMR; (4) qualitative evaluation of patient and health professional experience of LVMR and (5) 30-day morbidity and mortality rates.

Discussion: An individual-level, stepped-wedge, randomised trial serves the purpose of providing an untreated comparison for the active treatment group, while at the same time allowing the waiting-listed participants an opportunity to obtain the intervention at a later date. In keeping with the basic ethical tenets of this design, the average waiting time for LVMR (12 weeks) will be shorter than that for routine services (24 weeks).

Trial registration: ISRCTN registry, ISRCTN11747152 . Registered on 30 September 2015. The trial was prospectively registered (first patient enrolled on 21 March 2016).

Keywords: CapaCiTY; CapaCiTY study 3; Chronic constipation; Internal rectal prolapse; Laparoscopic ventral mesh rectopexy (LVMR); Rectopexy; Stepped wedge; Surgery.

Fig. 1

Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) diagram. MDT Multidisciplinary Decision Team, IBSQ Irritable Bowel Syndrome Questionnaire, LVMR Laparoscopic Ventral Mesh Rectopexy, PAC-QOL Patient Assessment of Constipation Quality of Life questionnaire, PAC-SYM Patient Assessment of Constipation Symptoms Questionnaire, EQ-5D EuroQol Health Outcome measure, EQVAS EuroQol visual analogue scale, PHQ-9 Patient Health Questionnaire -9, GAD7 Generalized Anxiety Disorder Questionnaire, CC chronic constipation, BIPQ Brief Illness Perception Questionnaire, AE adverse events, ConMeds concomitant medications, V visit, POPQ Pelvic Organ Prolapse Quantification System, Rome IIIQ constipation questionnaire based on the Rome III criteria, CC-BRQ Behavioural Response to illness Questionnaire