Public Reporting of Hospital-Acquired Infection Rates: The Case for Electronic Surveillance

The disclosure of hospital-acquired infection (HAI) rates to the general public is a movement that is gaining momentum across the United States. However, traditional manual surveillance for HAI, performed by infection preventionists (IPs), is hindered by the fact that the criteria for identifying cases of infection are complex and subjective, and are far from a diagnostic "gold standard". This raises serious concerns about the reliability of these criteria, particularly as they are applied by individuals with different levels of experience at different institutions. Simplified, objective criteria based only on microbiologic data may be a less valid, but potentially more reliable system for comparing institutional infection rates. We developed an agent-based model to examine the effect of validity and reliability on the measurement of catheter-related bloodstream infections (CRBSI) in a simulated hospital intensive care unit (ICU). Traditional (clinical-based) surveillance was performed by simulated IPs applying typical criteria; their reliability at interpreting subjective criteria was modeled using concepts derived from signal detection theory. Algorithmic surveillance was performed by applying simplified objective criteria to simulated patient data based on previously published work. We then measured the ability of these two surveillance methods to estimate each facility's true CRBSI rate, as well as to preserve the appropriate rank order of the facilities based on the estimates. Our results indicated that while simplified, objective CRBSI surveillance criteria are less accurate than traditional subjective clinical criteria at estimating an individual hospital's true CRBSI rate, they do appear to provide more accurate estimates of the true differences in CRBSI rates between institutions in most situations. Thus, the more reliable objective criteria are most likely better suited for measuring and publicly reporting institutional CRBSI rates if the ultimate goal is to allow comparisons between facilities. These findings could potentially have a significant impact on how HAI surveillance is performed, and how infection rates are estimated, at hospitals nationwide.