Objective: Service members undergoing disability evaluation are placed on the temporary disability retirement list (TDRL) when their disabling medical condition(s) may change in severity over time. Information is sparse on the epidemiology of the TDRL population and factors influencing time spent on the TDRL or changes in compensation ratings before final disability outcome. Methods: A cross-sectional study was conducted on U.S. Army, Navy, and Marine Corps personnel placed on the TDRL between fiscal years 2005 to 2009. Results: Approximately 85% of cases were finalized at first re-evaluation and more than 75% were permanently retired. Overall, about 50% of cases retained the same disability rating throughout the process. Cases with medical conditions within two or more body systems were more likely to be permanently retired and receive a change in disability rating than those with medical condition(s) within a single body system. Conclusions: Most cases retained the same disability rating and were permanently retired by the first re-evaluation. Important areas of future research include cost-benefit analyses to determine if length of time currently allowable on the TDRL can be shortened or if repeated evaluations are necessary and exploration of specific medical conditions likely to change in severity over time.