Occupational phorate exposure and cancer incidence The exposure measures in this study are an improvement. Whereas previous studies of pes- ticide exposures were limited to qualitative exposure measures, this study attempts to quan- tify cumulative lifetime exposure by incorporat- ing measures of frequency, duration, and intensity of exposure to speciﬁc pesticides. The measure of intensity used information such as application methods and PPE use to calculate a more precise measurement of actual exposure. Furthermore, the rate of recruitment and fol- low-up of participants was very high, as 82% of eligible participants enrolled, and < 2% were lost to follow-up. Although not all take-home questionnaires were returned, the measured dif- ferences between respondents and nonrespon- dents were not likely to be influential here (Tarone et al. 1997). Thus, the applicators returning the take-home questionnaire were likely representative of the overall cohort in terms of cancer risk. 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