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From page 1... ... These estimates come from regulatory health benefits analyses, which attempt to quantify changes in the expected cases of mortality and illness that are likely to result from proposed air pollution regulations. The estimates are often controversial, and the methods used to prepare them have been questioned. Read the entire page →
From page 2... ... , and other interested parties; reviewed materials submitted by EPA and others; and reviewed current literature relevant to health benefits estimation. The committee selected for detailed review the health benefits analyses contained in the regulatory impact assessments (RIAs) Read the entire page →
From page 3... ... THE COMMITTEE'S EVALUATION AND FINDINGS Despite many inherent uncertainties, the committee concludes that regulatory benefits analysis can be a useful tool for generating information valuable to policy-makers and the public. Properly conducted analyses can help identify the type, magnitude, end relative importance of hearth benefits, highlight the sensitivity ofthe benefits estimates to assumptions made in the analysis, and indicate the areas of greatest scientific uncertainty. Read the entire page →
From page 4... ... Therefore, the committee did not attempt to write a detailed manual for conducting benefits analysis but instead addressed the key methodological issues and their importance in the EPA benefits analyses reviewed by the committee. Regulatory Options, Boundaries, and Baselines The health benefits that are estimated to result from reducing air pollution depend on the decisions made at the beginning of the analysis regarding the regulatory options to consider, the health outcomes to evaluate, the time frame over which benefits are estimated, and the assumptions made about conditions with and without implementation of the regulation. Read the entire page →
From page 5... ... First, many important components of an emissions analysis, such as number of vehicles in a class, average miles traveled per vehicle, and emissions per mile, are seldom summarized for the benefits analysis. This lack of information makes it difficult to judge the plausibility ofthe emissions estimates. Read the entire page →
From page 6... ... EPA's approaches to exposure assessment evolved considerably over the period of the analyses reviewed by the committee as a result of continued improvement in the models and marked increase in available monitoring data for key pollutants. Overall, the methods used in the most recent EPA analysis reviewed by the committee (heavy-duty engine and diesel-fuel analysis) Read the entire page →
From page 7... ... Because scientific information on PM toxicity is incomplete, EPA has typically made the assumption of equivalent potency across particle types. The committee believes that benefits analyses would be strengthened by evaluating a range of alternative assumptions regarding relative particle toxicity in sensitivity or uncertainty analyses. Read the entire page →
From page 8... ... The EPA benefits analyses reviewed by the committee provided little information concerning this assumption. Although a comprehensive discussion of causality is not necessary for a benefits analysis, the evidence of causality shouIcl be summarized to justify the inclusion or exclusion of health outcomes end to assess the uncertainty associatedwith the assumption of causality. Read the entire page →
From page 9... ... Because epidemiological studies involve the study of humans in real-worId situations and, therefore, are more relevant to the assessment of health benefits than animal toxicity or human clinical studies, the committee supports the use of these studies to estimate concentration-response functions. However, the benefits analyses should reflect the plausibility and uncertainty of the concentration-response function, such as imprecision of exposure and response measures, potential confounding factors, and extrapolation from the study population to the target population in the benefits analysis. Read the entire page →
From page 10... ... Any assumptions that might explain the differences among subgroups should be clearly stated. Analysis of Uncertainty EPA uses a two-part approach to assess uncertainty in its health benefits analyses. Read the entire page →
From page 11... ... The ancillary analyses usually examine one source of uncertainty at a time and therefore do not adequately convey the aggregate uncertainty from other sources, nor do they discern the relative degrees of uncertainty in the various components of the health benefits analysis. EPA should move the assessment of uncertainty from its ancillary analyses into its primary analyses to provide a more realistic depiction ofthe overall degree of uncertainty. Read the entire page →
From page 12... ... Presentation of Results A common complaintaboutEPA's regulatory benefits analyses is that the methods, the rationale behind the decision-making, and the results are not clearly described or presented. After review of the EPA analyses, the committee agrees that the presentations should be improved. Read the entire page →
From page 13... ... � EPA should include in its regulatory benefits analyses comparative estimates of the benefits for several regulatory options that represent a realistic range of choices available to the decision-maker. If regulatory options are eliminated at an early stage, the rationale for the elimination should be provided. Read the entire page →
From page 14... ... � EPA should strive to present the results of its health benefits analyses in ways that avoid conveying an unwarranted degree of certainty, such as by rounding to fewer significant digits, increasing the use of graphs, and placing less emphasis on single numbers and more emphasis on ranges. � EPA should place the results of its health benefits analyses in context by referring not only to absolute numbers of avoided adverse health outcomes but also to total projected numbers of these outcomes and to population sizes. Read the entire page →
From page 15... ... � To enhance the quality of future regulatory benefits analyses, a standing, independent, technical review pane} should advise EPA in the initial stages of its benefits analysis. This panel should have expertise in regulatory options analysis, emissions and exposure assessment, toxicology, epidemiology, risk analysis, biostatistics, and economics and should be appointed with strict attention to avoiding conflict of interest, balancing biases, and ensuring broad representation. Read the entire page →
From page 16... ... Hall s~cUl~cc systems to ch~acted~e mo~idi~ outcomes, and (5) analyst of mixtures as weD as He single pollutant. Read the entire page →

From page 1...

... These estimates come from regulatory health benefits analyses, which attempt to quantify changes in the expected cases of mortality and illness that are likely to result from proposed air pollution regulations. The estimates are often controversial, and the methods used to prepare them have been questioned.

Summary Pages 1-16

Summary
Pages 1-16