Several studies have demonstrated there was subjective application of the NHSN HAI surveillance definitions by different IPs and facilities, prior to 2013.  During this time, the NHSN definitions allowed facilities to subjectively determine evidence that an infection was present or incubating on admission, which was not reportable to NHSN because it was not “healthcare-associated”.  Subjectivity, providing an opportunity for inconsistent data collection, must be removed from surveillance definitions whenever possible.  With this in mind, CDC and the HICPAC surveillance working group, a group made up of infectious disease professionals, healthcare epidemiologists, infection preventionists, and state public health representatives, developed a set of objective surveillance criteria to be implemented into NHSN and used by all facilities reporting data to NHSN.  Through the use of the same set of objective criteria it is expected that data reported to the system is useful for quality improvement activities.