“…Several studies of the 1918–20 influenza have also reported that in utero exposure to the pandemic was associated with various life outcomes that could have been a risk factor for poor mental health, e.g. higher rates of physical disability ( Almond, 2006 ), higher rates of chronic disease and hospitalization ( Acquah et al, 2017 ; Lin & Liu, 2014 ), and lower levels of education ( González et al, 2021 ; Lin & Liu, 2014 ; Percoco, 2016 ). However, it is also established that estimates of the effects of in utero exposure to 1918–20 pandemic can be both highly inconsistent ( Cohen et al, 2010 ; Vollmer & Wójcik, 2017 , p. 92) and systematically biased ( Beach et al, 2018 ; Brown & Thomas, 2018 ).…”