Use of the SF-36 questionnaire to predict quality-of-life improvement after laparoscopic colorectal resection for endometriosis

BACKGROUND: Laparoscopic colorectal resection for endometriosis can improve quality of life (QOL), but the results vary widely from one woman to another. The aim of this study was to determine whether the preoperative results on the Physical Component Summary (PCS) and Mental Component Summary (MCS) subscales of the SF-36 questionnaire could predict the improvement in QOL after surgery. METHODS: The predictive value of the subscales was first evaluated on a training set of 57 patients. A mathematical model, quantified with respect to discrimination and calibration was then applied to the validation set of 36 patients. RESULTS: Women with preoperative PCS and MCS scores below 37.5 and 44.5, respectively, had 80.7% and 84.2% probabilities of seeing their scores improve after surgery, whereas women with preoperative scores above 46.5 and 47.5, respectively, had probabilities of 0% and 10.7% to improve their scores. CONCLUSIONS: With our mathematical model, the postoperative improvement in QOL can be reliably predicted. This model should help to identify those women who are most likely to benefit from this major surgery.