Over the past decade, time-series studies conducted in many cities have contributed information about the association between daily changes in concentrations of airborne particulate matter (PM) and daily morbidity and mortality. In 2002, however, investigators at Johns Hopkins University and at Health Canada identified issues in the statistical model used in the majority of timeseries studies. This HEI Special Report details attempts to address several questions raised by these discoveries. The first section addresses the impact of the issues on the HEI-funded National Morbidity, Mortality, and Air Pollution Study (NMMAPS). The second section addresses the impact on additional studies selected by the US Environmental Protection Agency (EPA). Special Panels of the Health Effects Institute contributed Commentaries on the findings. (Author/publisher)
Samenvatting