Thomas Helfer, Ph.D.
Hearing Conservation outcome metrics have traditionally been based on the audiometric data stored in a data repository. These outcome metrics are generally derived from calculations performed on the objective data. Since 1997 there has been an additional set of outcome metrics available from the Ambulatory Data Module (ADM) and Composite Healthcare System (CHCS). Last year the DOD Military Injury Metrics Working Group published a white paper outlining the acquisition, storage, management, and reporting of military injury data. The source injury data are from the ADM and the CHCS. Injury metrics are expressed as categories of ICD-9 CM codes. Military injury data are stored at the Defense Medical Surveillance System at Walter Reed Army Medical Center. The DOD Military Injury Metrics Working Group concentrated on musculo-skeletal injuries and excluded hearing and eye injury ICD-9 codes altogether. The DOD Hearing Conservation Working Group submitted a list of hearing injury ICD-9 codes for incorporation into the military injury database. Of the 12 submitted only three were accepted for incorporation into the injury metrics database. The three accepted and other ICD-9 hearing injury codes include some that would come from the Audiology/ENT clinics separate from DOEHRS. There are codes for acoustic trauma, permanent threshold shift, Tinnitus, hearing losses affecting duty limits and retention in service. These hearing injury data from ADM will be available through the Medical Metrics (M2) database of the Executive Information/Decision Support (EI/DS) system. These are in addition to the outcome metrics stored in and reported from DOEHRS or the military injury databases. In order to “think populations” and take action to reduce risks, program managers should have access to ADM data as well as the DOEHRS data. This multi-source information fusion process allows managers to better evaluate program progress over time taking information from these separate data sources and putting them together to get clearer “situational awareness” regarding risk reduction. This process is called “evidence-based public health.”