TABLE 5.

Hospital Operative Volume Threshold Analysis

Operation	Average Risk-adjusted Mortality, %	Hospital Volume Threshold With 95% Chance of Being Better Than Average Mortality*	Total Number Hospitals	Percentage of Hospitals Not Achieving Volume Threshold, %	Total Operative Volume	Number of Operations Performed at Hospitals Below Volume Threshold	Percentage of Operations at Hospitals Below Volume Threshold, %
Appendectomy	0.9	61	305	25	52,905	2285	4
Cholecystectomy	1.5	75	310	24	69,052	2668	4
Colectomy	12.4	50	292	66	12,574	4423	35
Inguinal and femoral hernia	6.8	9	265	34	3757	483	13
Lysis of adhesions	7.1	19	292	38	9343	1110	12
Necrotizing soft tissue infection excision	13.2	11	228	55	2616	767	29
Repair of perforated peptic ulcer disease	17.8	13	245	78	2231	1267	57
Small bowel resection	12.1	37	280	73	7447	3450	46
Umbilical hernia	9.7	7	209	51	1737	470	27
Ventral hernia	7.1	10	259	46	3461	732	21

^*Hospital operative volume that optimizes probability of survival for a given operation, defined as the 2-year volume above which 95% of hospitals have better than average risk-adjusted mortality.