UC San Diego

This dissertation has three objectives : (1) assess agreement of injury data reported in two passive surveillance systems at the Marine Corps Recruit Depot, San Diego; (2) examine self-reported smoking as a risk factor for overuse injury among Marine Corps recruits; and (3) identify self-reported risk factors for poor training outcomes among Navy recruits. Five measurements of agreement were computed separately for sprains/strains, fractures/stress fractures, and all injuries between the two surveillance systems (objective 1). Recruits completed a baseline risk factor survey and were followed for overuse injury outcomes (objective 2), or graduation status (objective 3). Results : Objective (1) The data sets have a high proportion of negative agreement and low proportion of positive agreement, especially for fractures /stress fractures. The proportion of overall agreement between the two surveillance systems was extremely high for sprains/strains, and for fractures/stress fractures, and moderate for all injuries. Objective (2) Adjusted proportional hazard regression did not find a significant association with respect to smoking and overuse injury in either male or female Marine Corps recruits. Objective (3) Male Navy recruits who did not run or jog at least 1 month before basic training or had a previous lower limb injury without complete recovery, and females reporting the same or less physical activity compared to their same age counterparts, were more likely to have a poor training outcome. Conclusions : Objective (1) The large offsite surveillance system is better suited to provide historical baseline and post prevention injury rates than the locally maintained surveillance system, and therefore provide a better comparative estimate of the magnitude of each injury type after interventions are made. The local surveillance system is better suited to provide meaningful injury specific severity and exposure data needed to identify the impact and mechanism of injuries, information that can be used to introduce preventive measures in the field. Objective (2) Smoking does not appear to be an independent risk factor for overuse injury in either male or female Marine Corps recruits. Objective (3) An important first step in decreasing poor training outcomes in Navy recruits is to encourage incoming recruits to participate in physical activity, and take steps to identify and rehabilitate recruits who are not completely healed from a lower limb musculoskeletal injury before reporting to basic training