Abstract
Epidemiological studies of radiologists, radiologic technologists, and other medical radiation workers have been conducted in several countries. Since many of the study populations started radiological work before introduction of routine monitoring of occupational exposure, cancer risks have not been well examined in terms of exposure dose. Most of the studies used surrogate variables for exposure doses, e.g., calendar year employed, showing significantly higher cancer risks among those who worked in earlier periods. In Chinese and Japanese studies, occupational doses were estimated for sub-cohorts of the studies, based on information on past work history etc. In the US radiologic technologists study, occupational doses are being estimated using archived dosimetry records together with individual work histories and literature-based annual dose estimates for early periods. Although the reconstructed doses can involve much uncertainty, retrospective dosimetry in epidemiological studies of medical radiation workers is essential for better understanding of risk due to chronic exposure to low to moderate doses of radiation. [J Radiat Res 44:430 (2003)]
