Two-dimensional outcome analysis as a guide for quality assurance of prostatectomy

Purpose: To find outlier centers in different aspects of quality of care by comparing two different outcomes and adjusting to case mix in benign prostatic hypertrophy (BPH) patients undergoing prostatectomy. Materials and methods: An observational study including 537 consecutive patients undergoing prostatectomy for BPH in three medical centers in Israel between 1991 and 1992. Data were collected from medical charts and by a structured interview. Outcomes examined included immediate surgical complications and postoperative symptom effect level. Regression analysis was employed to adjust for case mix and to determine the additional contribution of medical centers. Results: We found significant variability among centers in crude symptom effect, but not after case mix adjustment. An outlier was detected in both the crude and case mix-adjusted urological complications. Conclusions: Centers may differ with various outcomes. This may reflect variability in different levels of performance within different aspects of the process of care in prostatectomy procedures.