Je. Watson et al., ESTIMATION OF RADIATION-DOSES FOR WORKERS WITHOUT MONITORING DATA FORRETROSPECTIVE EPIDEMIOLOGIC STUDIES, Health physics, 67(4), 1994, pp. 402-405
Dosimetry data are required for many epidemiologic studies of radiatio
n workers. For several reasons, these data may not be available for so
me workers for some periods of time. An estimate of a worker's dose fo
r such a time period can be made using data from nearby time periods f
or the worker or using data obtained for other workers during the same
time period. This paper reports the results of an evaluation of a pro
cedure for estimating external doses for workers included in retrospec
tive epidemiologic studies. This evaluation was conducted using data f
or workers who had recorded doses for each year in a 5-y period. The d
ose for the middle year of the 5-y period was treated as unavailable a
nd the dose was estimated several ways. These estimates were compared
with the recorded dose. It was observed that averaging a worker's dose
data for the years preceding and following a year for which data hypo
thetically were not available most often yielded the best estimate of
the dose. At one facility studied, the use of nearby data for the same
worker was a more reliable estimate for a dose than was the departmen
t or facility median or mean dose. However, at another facility, use o
f the department median or mean dose produced a more accurate estimate
than did nearby data for the worker. These results indicate that a si
ngle procedure for estimating doses is not best for all facilities, an
d it is recommended that a test of the type reported in this paper be
performed before a decision is made on how to estimate doses. The use
of department medians or means to estimate doses consistently produced
better estimates than were obtained using facility medians or means.