Demographic data (gender, age, race, grade and marital status) are provided by the Defense Manpower Data Center (DMDC), which receives updated data on a monthly basis from each service. The center also provides unit zip codes and Department of Defense (DOD) primary occupation codes, which allows for provision of data at the installation level and by occupational groupings. Inpatient hospitalization data are provided by the Executive Information and Decision Support (EIDS) Program Office and are a subset of information from the Standard Inpatient Data Record, which receives inpatient treatment data. Standard Inpatient Data Record data are collected by the Composite Health Care System at each DOD medical treatment facility (MTF) and the outsourced (non-DOD hospital) inpatient health care provided to active duty service members. At the time of discharge, for each hospitalization of an active duty service member in a U.S. military hospital, up to eight diagnoses are recorded using standard diagnostic codes from the International Classification of Diseases, 9th Revision (ICD-9). The first diagnosis is generally indicative of the primary reason for admission and is the diagnosis code that is reflected in DMED. Ambulatory data are provided by the EIDS Program Office. These data are a subset of the Standard Ambulatory Data Record, which records patient-level outpatient treatment data generated by the MTFs and the outsourced (non-DOD clinic) outpatient healthcare provided to active duty service members. Up to four diagnoses are recorded using standard ICD-9 diagnostic codes. Reportable events data contains information on 70 reportable medical events. These data are reported to DMSS by the Medical Surveillance Centers run by the military services. Army reportable event data are available for calendar years 1995 to present. Navy and Air Force data are available from calendar years 2000 to 16 July 2012.