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Patel MR, Shah S, Cabana MD, Sawyer SM, Toelle B, Mellis C, Jenkins C, Brown RW, Clark NM.Patel MR, et al. Among authors: sawyer sm.Prim Care Respir J. 2013 Mar;22(1):29-36. doi: 10.4104/pcrj.2012.00093.Prim Care Respir J. 2013.PMID: 23138841Free PMC article.