Adherence to the Centers for Disease Control and Prevention’s (CDC’s) Infection Definitions and Criteria is Needed to Ensure Accuracy, Completeness, and Comparability of Infection Information

CDC’s National Healthcare Safety Network (NHSN) is the nation’s most comprehensive medical event tracking system that is currently utilized by more than 16,000 U.S. healthcare facilities.  NHSN provides critical data to guide prevention efforts aimed at protecting patients.

In response to anecdotal reports of intentional non-reporting of infection data, CDC and CMS are jointly issuing a reminder that addresses concerns about healthcare facility non–reporting of healthcare-associated infections events.  While there is no evidence of a widespread issue, CDC and CMS want to emphasize that accurate reporting to NHSN through strict adherence to the NHSN definitions is critical.

CDC and CMS are committed to ensuring data accuracy and reliability for guiding prevention priorities and protecting patients. Identifying infections and making sure that patients receive the highest quality of care is our top priority.

Issue:   Ensuring data accuracy is critically important to both the Centers for Disease Control and Prevention (CDC) and the Centers for Medicare and Medicaid Services (CMS) for guiding prevention priorities and protecting patients. CDC and CMS require that all infections that meet the specified NHSN criteria and that CMS requires for incentive payment or public reporting purposes be reported to NHSN. CDC and CMS are issuing this communication to remind all hospitals of the importance of complete and accurate data for purposes of quality of care measurement and improvement.     

Background:  The CDC’s NHSN is the nation’s most comprehensive medical event tracking system used by more than 16,000 U.S. healthcare facilities in all 50 states, Washington, D.C., and Puerto Rico.  Data from NHSN is used for tracking of healthcare-associated infections and guides infection prevention activities that protect patients.  CMS and other payers use these data to determine incentives for performance and members of the public may use the data to select among available providers.   Each of these parties relies on the completeness and accuracy of the data. CDC and CMS are fully committed to ensuring complete and accurate reporting, which is critical for protecting patients and guiding national, state, and local prevention priorities.  Identifying infections and making sure that patients receive the highest quality of care is our top priority.

CDC has received reports from NHSN users indicating that in some healthcare facilities, some of the decisions about what infections should be reported to NHSN are made by individuals who may choose to disregard CDC’s protocol, definitions, and criteria or who are not thoroughly familiar with the NHSN specifications.  While there is no evidence of a widespread problem, CDC and CMS take any deviation from NHSN protocols seriously.

In some instances, these decisions may be made through a review process that overrules the decision of an infection preventionist or hospital epidemiologist to report an infection to NHSN, or clinicians may have departed from standard diagnostic practices to avoid reporting infections to NHSN, for example:

  • Ordering diagnostic tests in absence of clinical symptoms. It has been reported that in some instances, when patients are admitted to a hospital, diagnostic microbiology tests are ordered even in the absence of clinical indications for testing, such as obtaining urine specimens for culture and sensitivity testing from patients who have no symptoms of a urinary tract infection.  Many negative culture results are generated by this practice subjecting the patient to potentially unnecessary tests. On the occasion that a culture result is positive, the results are then used to assert that infections that first manifested themselves clinically many days later during hospitalization were present on admission and hence not reportable to NHSN. 
  • Discouraging the ordering of diagnostic tests in the presence of clinical symptoms.  It has been reported that in some instances clinicians responsible for inpatient care in some hospitals may be discouraged from ordering diagnostic microbiology tests recommended by best medical practices (or standards of care) to avoid test results that would make infections reportable to NHSN.  

In either case, systematic underuse or overuse of diagnostic microbiology testing puts patients at risk.  These practices can lead to use of antibiotics that is not necessary, such as treatment for bacterial colonization rather than infection, or antibiotic treatment that is not informed by culture results.  When diagnostic tests are used inappropriately, clinicians lose the opportunity to modify antibiotic choice in response to antibiotic susceptibility testing results and make better informed decisions for patients.  These practices could result in an increase in antibiotic resistant infections and adverse reactions among patients.

CDC and CMS underscore the importance of infection reporting by hospitals and other healthcare facilities for patient safety. All facilities should adhere to the NHSN protocol, definitions, and criteria to ensure the reliability and comparability of the data.  The value of NHSN for prevention, public reporting, federal incentive payments to provide quality healthcare and protect patients depends on the completeness and accuracy of data reported to the system by NHSN users in healthcare facilities throughout the U.S.  CDC works closely with healthcare professional organizations, state health departments, and the National Quality Forum in a broad-based, collaborative effort to ensure the NHSN protocol, definitions, criteria, and healthcare quality measure specifications are in accord with current clinical and laboratory practice.  CMS regulations require that healthcare facilities, in submitting data to the system in fulfillment of CMS quality reporting programs, adhere to the NHSN protocols, definitions, and criteria and participate in CMS’ validation process when selected for participation. 

If a clinician thinks that there is a problem with the specified criteria, CDC would appreciate hearing those concerns.  The agency continuously works to improve the definitions and criteria it maintains for infection surveillance, and in several instances, has refined its data collection instructions or clarified its definitions or criteria for identifying infections in response to issues brought to its attention by clinicians or hospitals.  In the meantime, however, the hospitals must adhere to the existing protocols, definitions, and criteria to ensure that its data are comparable to that of other organizations and to avoid revocation of NHSN enrollment or other penalties for failure to report data that are required by CMS’ incentive programs.  CMS quality measure reporting programs require that a responsible official must acknowledge the accuracy of the data at the time of its submission. Hospital staff who become aware of deviations from NHSN’s reporting protocols can utilize internal hospital or health system compliance processes to address the issue          

CMS reminds hospitals that intentionally reporting incorrect data, or deliberately failing to report data that are required to be reported, may violate applicable Medicare laws and regulations. The Department of Health and Human Services’ (HHS’s) Office of Inspector General (OIG) protects the integrity of HHS programs, including Medicare and Medicaid.  The Inspector General has the authority to exclude individuals and entities from participation in the Medicare, Medicaid, and other Federal healthcare programs and to impose Civil Monetary Penalties for certain misconduct related to Federal healthcare care programs.  Hospital staff who become aware of intentional deviations from NHSN reporting protocols are encouraged to report their concerns to the OIG hotline. 

Contacts:  For questions about the content of this notice, please contact: 

CDC Division of Healthcare Quality Promotion Policy Office
Phone: 404-639-4000

For questions or concerns about the protocols, specifications, or criteria specified for any of the NHSN measures, please

NHSN Helpdesk

For more information about the OIG go to: Suspected healthcare fraud and abuse can be reported to the OIG Hotline:

Phone: 1-800-HHS-TIPS (1-800-447-8477) 
Fax: 1-800-223-8164
TTY: 1-800-377-4950 or 
Mail: US Department of Health and Human Services
Office of Inspector General Attn: OIG Hotline Operations P.O. Box 23489
Washington, DC 20026