Table 2.

DEA Efficiency Scores (Bootstrap Bias-Corrected) by Model and Year

	Year
DEA Model	1997	1998	1999	2000	2001	2002	2003
1. Patient days, unadjusted*
Mean	0.376	0.365	0.367	0.353	0.339	0.329	0.328
SD	0.105	0.101	0.101	0.096	0.091	0.088	0.086
2. Patient days, acuity adjusted†
Mean	0.361	0.349	0.345	0.330	0.314	0.300	0.295
SD	0.102	0.098	0.098	0.091	0.086	0.082	0.079
3. Patient days, acuity and quality adjusted‡
Mean	0.198	0.188	0.172	0.156	0.140	0.136	0.131
SD	0.148	0.138	0.128	0.116	0.101	0.099	0.093
N	8,531	8,999	8,581	8,564	8,318	8,254	7,282

^*DEA scores obtained from unadjusted output/input measures.

^†DEA scores obtained from output/input measures, adjusted for acuity.

^‡DEA scores obtained from output/input measures, adjusted for acuity and quality.