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McKenzie TL, Nader PR, Strikmiller PK, Yang M, Stone EJ, Perry CL, Taylor WC, Epping JN, Feldman HA, Luepker RV, Kelder SH.McKenzie TL, et al.Prev Med. 1996 Jul-Aug;25(4):423-31. doi: 10.1006/pmed.1996.0074.Prev Med. 1996.PMID: 8818066Clinical Trial.