Protocol for Physiotherapy Or TVT Randomised Efficacy Trial (PORTRET): a multicentre randomised controlled trial to assess the cost-effectiveness of the tension free vaginal tape versus pelvic floor muscle training in women with symptomatic moderate to severe stress urinary incontinence. - Labrie J; van der Graaf Y; Buskens E; Tiersma SE; van der Vaart HC; Labrie, Julien; van der Graaf, Yolanda; Buskens, Eric; Tiersma, Stella E S M; van der Vaart, Huub C H (BMC Women's Health, 2009)