Center-by-center results of a multicenter prospective trial to determine the inter-observer correlation of the simplified POP-Q in describing pelvic organ prolapse

This study was conducted to determine the differences in the inter-observer agreement of the simplified Pelvic Organ Prolapse Quantification (POP-Q) system from center to center in a large international multicenter study. This is a secondary analysis of the results of a large prospective single blind multicenter trial studying the inter-observer agreement of a simplified POP-Q exam. Twelve centers from four continents with a total of 511 subjects were included in this study. The number of subjects recruited per center ranged from 20 to 81. Each patient was independently examined by two investigators, with examination order randomly assigned and investigators blinded to each other's result. The weighted kappa statistic was used to evaluate the inter-observer agreement. Good and significant associations were observed on the anterior, posterior, and apical segments. Six out of 11 sites did not provide adequate number of subjects with prior hysterectomy for weighted kappa statistics or achieve significance regarding vaginal cuff measurement. The simplified POP-Q demonstrated good inter-examiner agreement across multiple centers.