“…This search was then updated again in January 2016 in order to determine if additional publications should be included. All of the articles were then cross-referenced with a sampling of previously published literature reviews (Anthony and Walshaw, 2009; Carbonneau et al, 2013; Linder et al, 2013; MacDonald et al, 2012, 2016; Perry et al, 2008; Raghubar et al, 2010; Zaslow et al, 2010) in addition to a sample of highly cited articles published in top-tier early childhood or mathematics-focused journals (Camilli et al, 2010; Chang-Kredl and Kingsley, 2014; Duncan et al, 2007; Howes et al, 2008; McClelland et al, 2006; Magnuson et al, 2007).…”