This was a parallel two-arm, superiority, multicentre randomised controlled trial, which assessed the effectiveness of self-management compared to clinic-based care on prolapse-specific quality of life at 18 months for women who use a pessary for vaginal prolapse. The setting was NHS outpatient pessary clinics in the UK. The inclusion criteria were age ≥18 years, pessary use of any type/material (except Shelf, Gellhorn or Cube pessaries) and retention of a pessary for at least two weeks. Women were excluded if they had limited manual dexterity, were judged to have a cognitive deficit that prevented informed consent or self-management, were pregnant, or would have required the self-management teaching in a language other than English.
The primary outcome was prolapse-specific quality of life at 18 months, measured using the Pelvic Floor Impact Questionnaire-7 (PFIQ−7) (1), which ranges from 0 to 300 with higher scores indicating worse adverse impact. Secondary outcomes included participant-reported complications (study-specific Pessary Complications Questionnaire), general self-efficacy (the General Self-Efficacy Questionnaire) (2), pessary-specific self-efficacy (study-specific Pessary Confidence Questionnaire), and adverse events.
A sample size of 330 women (165 per group) was required to provide 90% power to detect a difference of 20 points in the PFIQ−7 score at 18 months after randomisation, assuming a standard deviation of 50, two-sided alpha of 0.05, and 20% loss to follow-up. Women were randomised to either self-management or clinic-based care on an even allocation basis. Group allocation was by remote web-based application, with minimisation by age, pessary user type (new or existing) and recruiting centre. No participants, researchers or those delivering the intervention were blinded to group allocation.
Women in the self-management group received a 30-minute self-management teaching appointment, an information leaflet, a two-week follow-up call and a support telephone number for their local centre. Women in the clinic-based care group returned to clinic as advised by the treating health care professional in line with that centre’s usual pessary practice. Women completed a baseline questionnaire and outcome data were collected via follow-up questionnaires at 6, 12 and 18 months post-randomisation.
A single final analysis was undertaken, with the primary analysis conducted according to the intention-to-treat principle with all randomised participants included. The PFIQ-7 was summarised using descriptive statistics by group for each time-point and comparisons between randomised groups were made using repeated measures mixed models. The analysis adjusted for baseline PFIQ-7 scores and minimisation covariates (age and pessary user type as fixed effects and centre as a random effect). The analysis of secondary outcomes was similar to PFIQ-7, other than repeated measures were not included in the mixed model for general self-efficacy and only counts were reported for adverse events. Pessary complications were measured for each participant by calculating the number of complications reported as a proportion of all the applicable complications listed in the Pessary Complications Questionnaire.
Sensitivity analyses of the primary outcome were carried out under a range of assumptions and analysis methods to investigate, for example, the effect of missing data and crossover. Subgroup analyses of the primary outcome were also conducted (subgroups were age <65 vs >=65, new vs existing pessary user and hysterectomy at baseline vs no hysterectomy at baseline).
A within-trial economic evaluation was conducted to compare the costs and benefits of self-management with clinic-based care over the 18 months after randomisation, measured in terms of quality adjusted life years (QALYs) which was the primary outcome for the cost-effectiveness analysis. Resource use data were collected using a study-specific Health Resource Use Questionnaire.