An Evaluation of Error of Acrylonitrile Measurements in an Epidemiologic Study

Abstract

Abstract An evaluation was undertaken of historical industrial hygiene measurement data used in a retrospective occupational epidemiologic study of acrylonitrile workers to determine if the presence, direction, and magnitude of measurement error could be identified. The data included over 12,000 measurements taken from 1977 to as late as 1987 in eight facilities. Because there was no gold standard, subsets of the data were examined for internal consistencies. Measurement error was probably random, as the companies used recognized sampling and analytic techniques. There was little difference between the summer and winter means, suggesting that any error due to season is likely to be small. Error due to shift assignment could not be evaluated; therefore, no action was taken by the study investigators to compensate for this type of error. Two other sources that were considered to have small errors were the duration of the measurement and the presence of censored data (measurements below the limit of detectio...