Abstract
Differential migration may provoke bias in an epidemiological assessment of the public health risks from exposure to environmental agents, particularly in ecologic studies of health outcomes with a long latency or induction period. The potential impact of migration bias on epidemiological research is complex, and it depends not only on the direction of the factor-related migration, but also on its extent. This study shows that even a small amount of differential migration can bias the assessment of the exposure–outcome relationship. Migration bias may result from a number of circumstances that are related to the way in which ‘populations’ are defined and ascertained. It is important to understand and minimise this type of bias in epidemiological research.
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Tong, S. Migration bias in ecologic studies. Eur J Epidemiol 16, 365–369 (2000). https://doi.org/10.1023/A:1007698700119
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DOI: https://doi.org/10.1023/A:1007698700119