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Chitwood DD, Page JB, Comerford M, Inciardi JA, McCoy CB, Trapido E, Lai SH.Chitwood DD, et al. Among authors: mccoy cb.Am J Public Health. 1991 May;81(5):631-3. doi: 10.2105/ajph.81.5.631.Am J Public Health. 1991.PMID: 1673049Free PMC article.