Outcome assessment with blinded versus unblinded POP-Q exams


      To determine whether blinded and unblinded Pelvic Organ Prolapse Quantification (POP-Q) examinations differ in a randomized trial.

      Study Design

      Blinded POP-Q examinations performed at 3 months and 1 year were compared with unblinded examinations performed by the surgeon in a randomized trial of vaginal mesh for pelvic organ prolapse.


      Sixty-five patients were included in the study. Correlations between the blinded and unblinded POP-Q points and stages varied from low to moderate (rho = 0.29-0.78). At 3 months, the blinded overall prolapse recurrence rate was 45.3% compared with 39.1% based on unblinded staging (P = .34). At 1 year, the blinded overall recurrence rate was significantly higher than the unblinded recurrence rate: 68.3% vs 53.3% (P = .004). The 1-year blinded anterior wall recurrence rate was also higher than the recurrence based on unblinded staging: 56.7% vs 43.3% (P = .021).


      Use of unblinded POP-Q staging resulted in underestimation of 1-year overall recurrence after prolapse repair.

      Key words

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