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Erickson BA, Schaeffer AJ, Van Le B.Erickson BA, et al. Among authors: schaeffer aj.BMJ Clin Evid. 2008 May 22;2008:1802.BMJ Clin Evid. 2008.PMID: 19450305Free PMC article.Review.
Schaeffer A, Jang T.Schaeffer A, et al.Clin Evid. 2005 Jun;(13):1110-9.Clin Evid. 2005.Update in: Clin Evid. 2006 Jun;(15):1252-62.PMID: 16135289Updated.Review.No abstract available.