Evaluating the Use of the Case Mix Index for Risk Adjustment of Healthcare-Associated Infection Data: An Illustration using Clostridium difficile Infection Data from the National Healthcare Safety Network

Details

• Alternative Title:
  Infect Control Hosp Epidemiol
• Personal Author:
  Thompson, Nicola D. ; Edwards, Jonathan R. ; Dudeck, Margaret A. ; Fridkin, Scott K. ; Magill, Shelley S.
• Description:
  BACKGROUND.
  
  Case mix index (CMI) has been used as a facility-level indicator of patient disease severity. We sought to evaluate the potential for CMI to be used for risk adjustment of National Healthcare Safety Network (NHSN) healthcare-associated infection (HAI) data.
  
  METHODS.
  
  NHSN facility-wide laboratory-identified Clostridium difficile infection event data from 2012 were merged with the fiscal year 2012 Inpatient Prospective Payment System (IPPS) Impact file by CMS certification number (CCN) to obtain a CMI value for hospitals reporting to NHSN. Negative binomial regression was used to evaluate whether CMI was significantly associated with healthcare facility-onset (HO) CDI in univariate and multivariate analysis.
  
  RESULTS.
  
  Among 1,468 acute care hospitals reporting CDI data to NHSN in 2012, 1,429 matched by CCN to a CMI value in the Impact file. CMI (median, 1.49; interquartile range, 1.36–1.66) was a significant predictor of HO CDI in univariate analysis (P < .0001). After controlling for community onset CDI prevalence rate, medical school affiliation, hospital size, and CDI test type use, CMI remained highly significant (P < .0001), with an increase of 0.1 point in CMI associated with a 3.4% increase in the HO CDI incidence rate.
  
  CONCLUSIONS.
  
  CMI was a significant predictor of NHSN HO CDI incidence. Additional work to explore the feasibility of using CMI for risk adjustment of NHSN data is necessary.
  
  
• Subjects:
  Clostridioides Difficile Clostridium Infections Cross Infection Hospitals Humans Incidence Predictive Value Of Tests Prevalence Risk Adjustment United States
• Keywords:
  Chlorination Household Water Treatment Safe Water Storage
• Source:
  Infect Control Hosp Epidemiol. 37(1):19-25
• Pubmed ID:
  26486597
• Pubmed Central ID:
  PMC6498436
• Document Type:
  Journal Article
• Funding:
  CC999999/Intramural CDC HHSUnited States/
• Volume:
  37
• Issue:
  1
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha256:877f648a5d11cb76dfa31e5eae1e5b6c6fedb7853ab1c099abaa78fbce7ee46c
• Download URL:
  https://stacks.cdc.gov/view/cdc/78338/cdc_78338_DS1.pdf
• File Type:
  [PDF - 239.22 KB ]