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Samuels RC, Liu J, Sofis LA, Palfrey JS.Samuels RC, et al. Among authors: palfrey js.Matern Child Health J. 2008 May;12(3):357-62. doi: 10.1007/s10995-007-0241-0. Epub 2007 Jun 20.Matern Child Health J. 2008.PMID: 17578657