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Schwab M, Syme SL.Schwab M, et al. Among authors: syme sl.Am J Public Health. 1997 Dec;87(12):2049-51; discussion 2051-2. doi: 10.2105/ajph.87.12.2049.Am J Public Health. 1997.PMID: 9431303Free PMC article.Review.No abstract available.