Details

Autor(en) / Beteiligte

• Klemm, Rebecca J.
• Mason, Robert M.
• Heilig, Charles M.
• Neas, Lucas M.
• Dockery, Douglas W.

Titel

Is Daily Mortality Associated Specifically with Fine Particles? Data Reconstruction and Replication of Analyses

Ist Teil von

• Journal of the Air & Waste Management Association, 2000-07, Vol.50 (7), p.1215-1222

Ort / Verlag

Pittsburgh, PA: Taylor & Francis Group

Erscheinungsjahr

2000

Quelle

Taylor & Francis

Beschreibungen/Notizen

• In 1996, Schwartz, Dockery, and Neas 1 reported that daily mortality was more strongly associated with concentrations of PM 2.5 than with concentrations of larger particles (coarse mass [CM]) in six U.S. cities ("original paper'V'original analyses"). Because of the public policy implications of the findings and the uniqueness of the concentration data, we undertook a reanalysis of these results. This paper presents results of the reconstruction of these data and replication of the original analyses using the reconstructed data. The original investigators provided particulate air pollution data for this paper. Daily weather and daily counts of total and cause-specific deaths were reconstructed from original public records. The reconstructed particulate air pollution and weather data were consistent with the summaries presented in the original paper. Daily counts of deaths in the reconstructed data set were lower than in the original paper because of restrictions on residence and place of death. The reconstruction process identified an administrative change in county codes that led to higher numbers of deaths in St. Louis. Despite these differences in daily counts of deaths, the estimated effects of par-ticulate air pollution from the reconstructed dataset, using analytic methods as described in the original paper, produced combined effect estimates essentially equivalent to the originally published results. For example, the estimated association of a 10 |j.g/m 3 increase in 2-day mean particulate air pollution on total mortality was 1.3% (95% confidence interval [CI] 0.9-1.7%, t = 6.53) for PM 25 based on the reconstructed dataset, compared to the originally reported association of 1.5% (95% CI 1.1-1.9%, t = 7.41). For coarse particles, the estimated association from the reconstructed dataset was 0.4% (95% CI -0.2-0.9%, t = 1.43) compared to the originally reported association of 0.4% (95% CI -0.1-1.0%, t = 1.48). These results from the reconstructed data suggest that the original results reported by Schwartz, Dockery, and Neas 1 were essentially replicated.