Air Pollution and Lung Cancer: A Review of Issues Affecting the Interpretation of the Epidemiological Literature

Report no. 15/18: The following report examines key issues that need to be considered when evaluating the attributes and implications of studies examining the association between ambient air pollution and lung cancer. Following a brief general discussion of the types of epidemiology studies that can be used to investigate the association between an environmental or occupational exposure and a particular health outcome, the report goes on to examine specific topics that need to be considered when evaluating the strength and weakness of any relationships that are purported to exist.

Areas of focus include exposure estimation, confounding, quantitative risk assessment, heterogeneity, and plausibility. Each of these topics is explored in detail and information is provided showing how reported relative risk estimates may have been impacted by the failure to fully evaluate or consider specific methodological, procedural, or interpretive characteristics of the study. As such, the aim of the report is to highlight some generally overlooked areas of inquiry that need to be addressed in order to frame and draw conclusions from the results of a chronic health effects investigation focusing on lung cancer and air pollutant exposures.