Table 2. Hospital Factors Associated With False-Positive and False-Negative CUSUM Signaling (Relative to Observed to Expected Ratio), Stratified by Single vs Multiple Quarterly CUSUM Signals.
| Factor | Odds ratio (95% CI) | |||
|---|---|---|---|---|
| Single CUSUM signal | Multiple CUSUM signals | |||
| False positive | False negative | False positive | False negative | |
| Size | ||||
| Hospital operating beds per 10 000 veteran users, No. | 1.00 (0.99-1.02) | 1.00 (0.95-1.06) | 1.00 (0.98-1.03) | 1.02 (0.61-1.67) |
| Complexity levela | ||||
| 3 | 1 [Reference] | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| 2 | 2.86 (0.30-26.76) | 1.03 (0.13-8.03) | 0.14 (0.05-0.45) | 7.95 (0.85-74.25) |
| 1c | 11.53 (1.26-105.52) | 0.17 (0.02-1.43) | 0.48 (0.22-1.07) | 1.20 (0.21-6.97) |
| 1b | 15.33 (1.63-144.30) | 0.24 (0.02-3.18) | 0.84 (0.47-1.49) | 0.49 (0.11-2.18) |
| 1a | 16.95 (1.77-162.09) | 0.45 (0.03-6.47) | 1.00 (1.00-1.00) | 1.00 (1.00-1.00) |
| Disease burden | ||||
| Mean relative risk scoreb | 0.66 (0.20-2.14) | 1434.06 (31.29-65 724.32) | 0.61 (0.12-3.04) | 3.16 (0.05-214.99) |
| Academic mission | ||||
| Resident slots per 10 000 Veteran users | 1.02 (1.00-1.05) | 0.90 (0.84-0.98) | 1.01 (0.98-1.05) | 0.95 (0.88-1.03) |
| Reliance on VA | ||||
| Reliance of Medicare-eligible enrollees on VAc | 16.90 (1.23-232.93) | 0.001 (0.001-0.086) | 9.60 (0.28-324.29) | 0.002 (0.000-8.459) |
| Infrastructure | ||||
| Multisite | 1.24 (0.73-2.09) | 5.29 (0.97-28.92) | 0.80 (0.40-1.61) | 1.00 (0.14-7.10) |
| Square footage per unique veteran userd | 0.97 (0.95-1.00) | 1.02 (0.96-1.09) | 1.00 (0.97-1.03) | 1.00 (0.93-1.08) |
| Care delivery structure | ||||
| Ratio of nonhospital-based outpatient visits to total visits | 0.52 (0.11-2.38) | 13.32 (0.39-452.05) | 0.42 (0.05-3.57) | 1.41 (0.02-121.11) |
| Community and environment | ||||
| Community hospital beds per patient, No. | 1.09 (0.49-2.43) | 4.51 (0.95-21.30) | 0.63 (0.19-2.12) | 5.03 (0.40-63.15) |
| Total Medicaid generositye | 1.00 (1.00-1.00) | 1.00 (1.00-1.00) | 1.00 (1.00-1.00) | 1.00 (1.00-1.00) |
| SAIL Quality Scoref | ||||
| 1 | 1 [Reference] | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| 2 | 1.40 (0.69-2.84) | 2.77 (0.49-15.52) | 1.37 (0.53-3.56) | 1.44 (0.29-10.29) |
| 3 | 1.07 (0.53-2.17) | 2.59 (0.49-13.63) | 0.94 (0.36-2.49) | 1.22 (0.20-7.62) |
| 4 | 1.04 (0.48-2.25) | 2.83 (0.52-15.51) | 1.00 (0.34-2.91) | 1.79 (0.25-12.59) |
| 5 | 1.07 (0.43-2.65) | 2.91 (0.17-50.19) | 1.10 (0.32-3.74) | 1.60 (0.11-23.75) |
Abbreviations: CUSUM, cumulative sum; SAIL, Strategic Analytics for Improvement and Learning; VA, US Department of Veterans Affairs.
VA facilities are divided into 5 levels of complexity (1a, 1b, 1c, 2, and 3, with 1a being the highest complexity and 3 being the lowest) based on factors including patient risk, teaching, research, volume, number of physician specialists, and availability of intensive care units.20
Veterans’ estimated health care costs divided by mean observed health care costs of an individual in the VA.
VA cost divided by the sum of VA cost and Medicare cost.
Building square footage plus leased square footage.
Adjusted total Medicaid spending by the state divided by number of state residents with income below the federal poverty level.
Assessment of 27 quality measures, such as mortality rate, complications, patient satisfaction, and overall efficiency, for hospital system performance within the VA.