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SIR Model Explorer
CLABSI, CAUTI, MRSA Bacteremia LabID, CDI LabID
CDI LabID Event Risk Adjustment (IRFs)
The number of predicted CDI LabID 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 | -9.4497 | 0.1627 | <0.0001 |
| Free-standing HOSP-REHAB with inpatient CO prevalence rate1 >0 per 100 admissions | 0.3824 | 0.1100 | 0.0005 |
| Free-standing HOSP-REHAB with inpatient CO prevalence rate1 = 0 per 100 admissions OR IRF Unit within a hospital | REFERENT | – | – |
| CDI test type2: NAAT or Other | 0.2352 | 0.0578 | <0.0001 |
| CDI test type2: EIA | REFERENT | – | – |
| Proportion of admissions with stroke3: <0.185 | 0.3108 | 0.0973 | 0.0014 |
| Proportion of admissions with stroke3: 0.185-0.320 | 0.1862 | 0.0908 | 0.0402 |
| Proportion of admissions with stroke3: ≥0.321 | REFERENT | – | – |
| Proportion of admissions with orthopedic conditions3:
<0.110 |
0.3103 | 0.0691 | <0.0001 |
| Proportion of admissions with orthopedic conditions3:
≥0.110 |
REFERENT | – | – |
| Average daily census3: ≥51.3 patients | 0.2127 | 0.0657 | 0.0012 |
| Average daily census2: <51.3 patients | REFERENT | – | – |
| Proportion of admissions with non-traumatic spinal cord dysfunction3: ≥0.012 | 0.2822 | 0.1323 | 0.0330 |
| Proportion of admissions with non-traumatic spinal cord dysfunction3: <0.012 | REFERENT | – | – |
| Proportion of admissions with traumatic spinal cord dysfunction3: <0.016 | 0.1660 | 0.0640 | 0.0095 |
| Proportion of admissions with traumatic spinal cord dysfunction3: ≥0.016 | REFERENT | – | – |
Footnotes:
1 Inpatient community-onset (CO) prevalence rate is calculated as the # inpatient CO de-duplicated CDI events, divided by total admissions * 100 (CDIF_admPrevCOCount_bs3/numadms * 100). The prevalence rate for the entire quarter is used in risk adjustment.
2 CDI test method is reported on the FacWideIN (HOSP-REHAB) or IRF unit MDRO/CDI denominator form on the 3rd month of each quarter. CDI test type is categorized as:
- Nucleic acid amplification test (NAAT) or Other: This includes NAAT, GDH plus NAAT (GDHNAAT), GDH plus EIA for toxin, followed by NAAT for discrepant results (GDHEIA), toxigenic culture (ToxiCul), cell cytotoxicity neutralization assay (Cyto), and the selection of ‘Other’ (OTH).
- Enzyme immunoassay (EIA) for toxin: This includes EIA for toxin, glutamate dehydrogenase (GDH) antigen plus EIA for toxin, and NAAT plus EIA, if NAAT positive (2-step algorithm) (NAATEIA).
3 Average daily census and proportion of admissions with primary diagnoses are reported or calculated from values reported on the Annual IRF Survey [PDF – 1 MB]. Proportion of admissions with primary diagnosis is calculated as the # of admissions with the primary diagnosis / total # of annual admissions.
