Laboratory Measurement Error in External Dose Estimates and its Effects on Dose-Response Analyses of Hanford Worker Mortality Data.
Gilbert ES; Fix JJ
Pacific Northwest National Laboratory, U.S. Department of Energy, Battelle Memorial Institute 1996 Aug; :1-31
The effects of laboratory measurement errors on external radiation dose estimates and the resulting effects on linear dose response analyses of mortality data from epidemiologic studies of cancer in nuclear workers were examined. Three statistical models that expressed the variance or uncertainty in radiation exposure measurements made by personal dosimeters were applied to estimates of variance associated with risk sets derived from analyses of cancer mortality in workers employed at the Hanford Laboratory in Washington State between 1945 and 1986. The models were based on a linear relative risk model, a classical error model, and an exponential model. Workers with confirmed internal intakes of radionuclides or who had received a substantial proportion of their dose from neutrons or low energy (below 100 kiloelectron volts) photons were excluded from analysis. This left a total of radiation exposure data associated with 1,426 cancer deaths for analysis. The models were applied to computing the R-statistic, defined as the ratio of the variance in the true dose to the variance in the measured dose. All three models predicted that the value of the R- statistic would be close to 1, indicating that the error, or variance, in the measured radiation doses was unlikely to amount to more than 1% of the variance in the true dose. The authors conclude that although errors from other sources need to be addressed in epidemiologic studies, the results of this study show that errors resulting from laboratory sampling variation are unlikely to distort the results.
NIOSH-Grant; Grants-other; Radiation-exposure; Dosimetry; Dose-response; Laboratory-workers; Epidemiology; Statistical-analysis; Mortality-data; Malignant-neoplasms; Mathematical-models; Ionizing-radiation;
Health Risk Assessment Dept Battelle Memorial Inst PO Box 999 Msin P7 82 Richland, WA 99352
Final Grant Report
Other Occupational Concerns; Grants-other
Pacific Northwest National Laboratory, U.S. Department of Energy, Battelle Memorial Institute
Battelle Pacific Northwest Laboratories, Richland, Washington