Standard Vocabulary and CDC's National Healthcare Safety Network (NHSN)

The National Healthcare Safety Network (NHSN) is a web-based system developed and maintained by CDC’s Division of Healthcare Quality Promotion (DHQP) and used for surveillance of healthcare-associated infections (HAIs), antimicrobial resistance, and adherence to clinical practices known to prevent infections.  NHSN’s technical design enables data entry via secure web pages or file transfers (standard electronic messages or documents) via secure internet connections.  Standard vocabulary is an integral part of NHSN’s web-based application and a resource for implementers of message- and document-based solutions for data transmission to NHSN.  The wide-ranging vocabulary requirements for the system include healthcare service locations, specific types of HAIs, clinical findings, concept identifiers for the microorganisms that cause HAIs, and antimicrobial susceptibility test names and test results for those pathogens.  DHQP staff are working closely with colleagues in CDC’s National Center for Public Health Informatics (NCPHI), other CDC programs, and standards development organizations to map NHSN vocabulary, legacy and new terms alike, to standard terminologies, including LOINC, SNOMED, and HL7-maintained vocabularies.  DHQP staff also are working closely with NCPHI on enabling access and distribution of NHSN vocabulary through PHIN VADS.  Lessons learned from these efforts provide insights into the challenges of developing and implementing vocabulary standardization in a CDC surveillance system.