“…We included 56 studies that reported the mean and/or median age at ASD diagnosis, of which 46 reported an overall ASD mean age at diagnosis between 30.9 and 574.4 months (Becerra-Culqui et al, 2018; Begeer et al, 2013; Bello-Mojeed et al, 2017; Bent et al, 2015; Berg et al, 2018; Bravo Oro et al, 2012; Brett et al, 2016; Carias & Wevrick, 2019; Cawthorpe, 2018; Crane et al, 2016; Daniels et al, 2017; Darcy-Mahoney et al, 2016; Emerson et al, 2016; Garrido et al, 2018; Goodwin et al, 2017; Hagberg & Jick, 2017; Hall-Lande et al, 2018; Hausman-Kedem et al, 2018; Höfer et al, 2019; Hrdlicka et al, 2016; Jo et al, 2015; Kentrou et al, 2019; Kurasawa et al, 2018; Lagunju et al, 2014; Larsen, 2015; Lo et al, 2017; Magaña et al, 2013; Manohar et al, 2019; Martinez et al, 2018; Masri et al, 2013; May et al, 2017; Mazurek et al, 2014; Miodovnik et al, 2015; Mishaal et al, 2014; Mpaka et al, 2016; Ribeiro et al, 2017; Rutherford et al, 2016; Salomone et al, 2016; Sheldrick et al, 2017; Shrestha et al, 2019; Sicherman et al, 2017; Talero-Gutiérrez et al, 2012; Ververi et al, 2012; Wei et al, 2018; Zablotsky et al, 2018). Of the 56 studies, 24 reported an overall ASD median age at diagnosis (only or combined with mean age at diagnosis score) between 28 and 96 months (Baio et al, 2018; Becerra-Culqui et al, 2018; Bent et al, 2015;…”