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Vahratian A, Siega-Riz AM, Savitz DA, Zhang J.Vahratian A, et al. Among authors: zhang j.Ann Epidemiol. 2005 Aug;15(7):467-74. doi: 10.1016/j.annepidem.2005.02.005.Ann Epidemiol. 2005.PMID: 15921926