1160. Using Medicare Claims to Identify U.S. Hospitals with a High Rate of Surgical Site Infection Following Hip Arthroplasty
Session: Poster Abstract Session: Surveillance HAIs: Advancing the Science
Friday, October 19, 2012
Room: SDCC Poster Hall F-H
  • Calderwood_IDSA2012_Hip_Arthroplasty_Poster_Submitted.pdf (489.5 kB)
  • Background: Surgical site infections (SSIs) are serious and costly complications of surgery. They are the target of public reporting and of “pay-for-performance” programs aimed at improving the quality of hospital care. Current surveillance methods have many known flaws. The objective of this study was to assess the ability of Medicare claims to identify U.S. hospitals with high rates of SSI following hip arthroplasty.

    Methods: We conducted a retrospective cohort study of fee-for-service Medicare patients 65 years and older who underwent hip arthroplasty in U.S. hospitals from 2005 through 2007. Hospital rankings were derived from claims codes suggestive of SSI, adjusted for age, gender, and comorbidities, while using generalized linear mixed models to account for hospital volume. Medical records were obtained for validation of infection in a random sample of patients from hospitals ranked in the best and worst deciles of performance. Our main outcome measure was the risk-adjusted odds of developing a chart-confirmed SSI following hip arthroplasty in hospitals ranked by claims into the worst- versus best-performing deciles.

    Results: Among 524,892 eligible Medicare patients undergoing hip arthroplasty at 3,296 U.S. hospitals, a patient undergoing surgery in a hospital ranked in the worst-performing decile based on claims-based evidence of SSI had a 2.9-fold higher odds of developing a chart-confirmed SSI relative to a patient with the same age, gender, and comorbidities in a hospital ranked in the best-performing decile (95% confidence interval 2.2-3.7).

    Conclusion: Medicare claims successfully distinguished between hospitals with high and low SSI rates following hip arthroplasty. These claims can identify potential outlier hospitals that merit further evaluation. This strategy can also be used to validate the completeness of public reporting of SSI.

    Michael S. Calderwood, MD, MPH1,2, Ken Kleinman, ScD2, Dale Bratzler, DO, MPH3,4, Allen Ma, PhD4, Christina Bruce, BA2, Rebecca E. Kaganov, BA2, Claire Canning, MA2, Richard Platt, MD, MS, FSHEA2, Susan S. Huang, MD, MPH, FIDSA5 and for the CDC Prevention Epicenters Program and the Oklahoma Foundation for Medical Quality, (1)Infectious Diseases, Brigham and Women's Hospital, Boston, MA, (2)Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, MA, (3)College of Public Health, University of Oklahoma Health Sciences Center, Oklahoma City, OK, (4)Oklahoma Foundation for Medical Quality, Oklahoma City, OK, (5)University of California Irvine School of Medicine, Orange, CA


    M. S. Calderwood, None

    K. Kleinman, None

    D. Bratzler, None

    A. Ma, None

    C. Bruce, None

    R. E. Kaganov, None

    C. Canning, None

    R. Platt, None

    S. S. Huang, None

    Findings in the abstracts are embargoed until 12:01 a.m. PST, Oct. 17th with the exception of research findings presented at the IDWeek press conferences.