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Crawford SE, David MZ, Glikman D, King KJ, Boyle-Vavra S, Daum RS.Crawford SE, et al.J Am Board Fam Med. 2009 Nov-Dec;22(6):647-54. doi: 10.3122/jabfm.2009.06.090025.J Am Board Fam Med. 2009.PMID: 19897693Free article.