fatal disease. The Medical Follow-up Agency chose a study cohort of about one quarter of the test participants in the five series identified below: Series GREENHOUSE UPSHOT KNOTHOLE CASTLE REDWING PLUMBBOB Year Location 1951 1953 1954 1956 PPG* NTS*x PPG PPG 1957 No. of Detonations 4 11 6 17 NTS 24 *Pacific Proving Ground **Nevada Test Site As for the CDC study of Shot SMOKY, complete rosters of participants in these series did not exist. The Nuclear Test Personnel Review (NTPR) teams, using such sources as ship deck logs, unit morning reports, special orders, after-action reports, and film badge dosimetry logs, identified by name a total of 49,148 participants by March 1983. cohort for the NRC study. This list was selected as the Only persons identified from valid records were included in the study; self-reported participants were not accepted by NAS. Because of the large number of participants, tracing each individual's health status, in particular for incidence of disease, was considered impractical for both technical and financial reasons. It was decided, therefore, to limit the study to mortality and to use records maintained by the Veterans Administration. A mortality study would indicate any unusual incidence and would tell if a morbidity study was warranted. Names and other identification, such as social security numbers, were submitted to the VA Beneficiary Identification and Records Locator Subsystem (BIRLS) to ascertain who had died through 1982 and the location of their VA records. Death certificates for those confirmed dead by the BIRLS were ordered from the VA regional offices. No record existed in the BIRLS for many of the names submitted. These names were directed to the National Personnel Records Center (NPRC) in St. Louis, Missouri, for further research using such files as the VA Master Index. 186