Guidelines as to what constitutes an adverse respiratory health effect, with special reference to epidemiologic studies of air pollution

The following guidelines were developed to assist the lung associations and primary care physicians in the interpretations of the epidemiologic literature on what constitutes an adverse respiratory health effect of air pollution. Adverse health effects caused by air pollution are listed in hierarchical order, with the most severe at the top and the least severe at the bottom. Where one draws the line to categorize it as an adverse health effect or an action level between pathophysiologic or physiologic change is probably best left to the individual or the community.