“…Average age was reported differently amongst the studies, organized either by age at first tube placement, age at lip or palate repair, age at time of study, and age at myringoplasty. Study subjects originated from 13 countries: Canada (Knapik and Saliba, 2012), Finland (Klockars and Rautio, 2012; Lehtonen et al, 2016), France (Rieu-Chevreau et al, 2019), Germany (Reiter et al, 2009), Japan (Kobayashi et al, 2012; Inoue et al, 2020), Taiwan (Yang et al, 2019), Turkey (Kuşcu et al, 2015), South Korea (Ahn et al, 2012), Spain (Garcia-Vaquero et al, 2018), Sweden (Tengroth et al, 2017), Switzerland (Ezzi et al, 2015; Kapitanova et al, 2018), the United Kingdom (Andrews et al, 2004; Merrick et al, 2007; Fitzsimons et al, 2017), and the United States (Goudy et al, 2006; Brgoch et al, 2015; Imbery et al, 2017; Kim et al, 2017; Shaffer et al, 2018; Koempel et al, 2021). More than half (13/23) of these studies were conducted using a retrospective cohort study design; the remaining studies consisted of 4 retrospective case series (Merrick et al, 2007; Imbery et al, 2017; Tengroth et al, 2017; Koempel et al, 2021), 3 cross-sectional studies (Andrews et al, 2004; Brgoch et al, 2015; Garcia-Vaquero et al, 2018), 2 case-control studies (Merrick et al, 2007; Inoue et al, 2020), and 1 prospective cohort study (Kobayashi et al, 2012).…”