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SIR Model Explorer
CLABSI, CAUTI, MRSA Bacteremia LabID, CDI LabID
CDI LabID Event Risk Adjustment (LTACHs)
The number of predicted CDI Lab ID events under the 2022 baseline is calculated using a negative binomial regression model and is risk adjusted based on the following variables found to be statistically significant predictors of CDI incidence. Information about the statistical properties of NHSN risk adjustment models, including how the number of predicted events is calculated, is available in NHSN’s Guide to the SIR (2022 baseline) [PDF – 1MB].
| Parameter | Parameter Estimate | Standard Error | P-value |
| Intercept | -9.6565 | 0.2476 | <0.0001 |
| Proportion of admissions on hemodialysis1: >0 | 0.9840 | 0.2174 | <0.0001 |
| Proportion of admissions on hemodialysis1: 0 | REFERENT | – | – |
| Inpatient CO prevalence rate2: >0 per 100 admissions | 0.4575 | 0.1121 | <0.0001 |
| Inpatient CO prevalence rate2: 0 per 100 admissions | REFERENT | – | – |
| Average length of stay1: <25.3 days | 0.4027 | 0.1157 | 0.0005 |
| Average length of stay1: ≥29.4 days | 0.2451 | 0.0982 | 0.0126 |
| Average length of stay1: 25.3-29.3 days | REFERENT | – | – |
| Proportion of beds that are high observation1: <0.238 | 0.3083 | 0.0979 | 0.0016 |
| Proportion of beds that are high observation1: ≥0.238 | REFERENT | – | – |
| Proportion of admissions on a ventilator1: ≥0.141 | 0.2363 | 0.0915 | 0.0099 |
| Proportion of admissions on a ventilator1: <0.141 | REFERENT | – | – |
| Number of ICU beds1: >0 beds | 0.1707 | 0.0772 | 0.0271 |
| Number of ICU beds1: 0 beds | REFERENT | – | – |
Footnotes:
1 Proportion of admissions on hemodialysis, average length of stay, proportion of beds that are high observation, proportion of admissions on a ventilator, and number of ICU beds are reported or calculated from values reported on the Annual LTACH Survey [PDF – 1MB]. Average length of stay is calculated as: total # of annual patient days / total # of annual admissions. Proportion of admissions on hemodialysis is calculated as: # admissions on hemodialysis / total # of annual admissions. Proportion of beds that are high observation is calculated as: # high observation, special care, or high acuity beds / total # of beds.
2 Inpatient community-onset (CO) prevalence is calculated as the # of inpatient CO CDI de-duplicated events, divided by total admissions * 100 (i.e., cdif_admPrevCOCount_bs3 / numadms * 100). The prevalence rate for the entire quarter is used in risk adjustment.
