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VanderWaal CJ, Powell LM, Terry-McElrath YM, Bao Y, Flay BR.VanderWaal CJ, et al. Among authors: powell lm.J Prim Prev. 2005 Jul;26(4):299-320. doi: 10.1007/s10935-005-5390-6.J Prim Prev. 2005.PMID: 15995801Free article.