Pelvic floor muscle training versus watchful waiting or pessary treatment for pelvic organ prolapse (POPPS): design and participant baseline characteristics of two parallel pragmatic randomized controlled trials in primary care.

Pelvic floor muscle training (PFMT) and pessaries are commonly used in the conservative treatment of pelvic organ prolapse (POP). Because there is a lack of evidence regarding the optimal choice between these two interventions, we designed the "Pelvic Organ prolapse in primary care: effects of Pelvic floor muscle training and Pessary treatment Study" (POPPS). POPPS consists of two parallel open label randomized controlled trials performed in primary care, in women aged ≥55 years, recruited through a postal questionnaire. In POPPS trial 1, women with mild POP receive either PFMT or watchful waiting. In POPPS trial 2, women with advanced POP receive either PFMT or pessary treatment. Patient recruitment started in 2009 and was finished in December 2012. Primary outcome of both POPPS trials is improvement in POP-related symptoms. Secondary outcomes are quality of life, sexual function, POP-Q stage, pelvic floor muscle function, post-void residual volume, patients' perception of improvement, and costs. All outcomes are measured 3, 12, and 24 months after the start of treatment. Cost-effectiveness will be calculated based on societal costs, using the PFDI-20 and the EQ-5D as outcomes. In this paper the POPPS design, the encountered challenges and our solutions, and participant baseline characteristics are presented. For both trials the target numbers of patients in each treatment group are achieved, giving this study sufficient power to lead to promising results.