2003 Fiscal Year Final Research Report Summary
Statistical Model for evaluating health effects of dioxins around waste incinerators
Project/Area Number |
13480072
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Statistical science
|
Research Institution | National Institute of Public Health |
Principal Investigator |
TANGO Toshiro National Institute of Public Health, Department of Technology Assessment and Biostatistics, Director, 技術評価部, 部長 (70124477)
|
Co-Investigator(Kenkyū-buntansha) |
YAMAOKA Kazue National Institute of Public Health, Department of Technology Assessment and Biostatistics, Section Chief, 技術評価部, 室長 (50091038)
OGATA Hiromitsu National Institute of Public Health, Center for Information Research and Library, Section Chief, 研究情報センター, 室長 (50185500)
|
Project Period (FY) |
2001 – 2003
|
Keywords | dioxins / Poisson distribution / score test / Monte Carlo simulation / GIS |
Research Abstract |
There has been great public concern that adverse reproductive health effects may be associated with dioxins in emission gases from municipal solid waste (MSW) incinerators. Recently, Japan's first-ever large scale nationwide epidemiological study has begun to examine the association of adverse reproductive outcomes with mothers living within 10km from 63 MSW incinerators with high dioxin emission levels (above 80ng international toxic equivalents TEQ/m^3) in Japan. The primary purpose of our study was to investigate the statistical method to analyze the data collected in the above study and also to propose a method applicable to more general problems of raised disease risk around putative point sources. As statistical method to detect such clusters, Stone's maximum likelihood ratio test and score tests which score each case the reciprocal of the distance from a point source are popular. In our study, we have proposed extensions of score tests based on small area data in that (i)it allows us to select the best among prespecified parametric exposure functions to avoid multiple testing problems and (ii)it can be applied to a possible situation where the hazardous substance levels tend to peak at some distance from a point source. The properties of the proposed tests and their power have been examined and illustrated with hypothetical data and also the power calculation has been conducted on the study design of above-stated epidemiological study. Simulation study shows that the powers of the proposed tests are higher than that of Stone's test over all the alternatives considered.
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