“…Extending our recent work on bystander selection (Tedijanto et al, 2018), we used the 2015 National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey (NAMCS/NHAMCS) (National Center for Health Statistics, 2015a, 2015b), the Human Microbiome Project (HMP) (Huttenhower et al, 2012; The Human Microbiome Project Consortium, 2012), and assorted carriage and etiology studies (Bäckhed et al, 2015; Bluestone, Stephenson, & Martin, 1992; Bogaert et al, 2011; Brook, Thompson, & Frazier, 1994; Celin, Bluestone, Stephenson, Yilmaz, & Collins, 1991; Chira & Miller, 2010; Edlin, Shapiro, Hersh, & Copp, 2013; Ginsburg et al, 1985; Gunnarsson, Holm, & Söderström, 1997; Gupta et al, 1999; Jack M. Gwaltney, Scheld, Sande, & Sydnor, 1992; Hammitt et al, 2006; Holgerson, Öhman, Rönnlund, & Johansson, 2015; Susan S. Huang et al, 2009; Jain et al, 2015; Arch G. Mainous, Hueston, Everett, & Diaz, 2006; Pettigrew et al, 2012; Regev-Yochay et al, 2004; Verhaegh et al, 2010; Loretta Wubbel et al, 1999; Yassour et al, 2016) (details in Figure 1 – Source Data File 1) to estimate national outpatient antibiotic exposures by drug, species, and condition.…”