In Reply We thank Pichini et al for their comments on our article.1 Pichini et al expressed concern that Italy was reported to be among the 5 countries with the highest prevalence of fetal alcohol spectrum disorder (FASD) globally (45.0 per 1000 or 4.5%; 95% CI, 35.1-56.1 per 1000 or 3.5%-5.6%). It is interesting that they expressed similar concern regarding our prevalence estimates of fetal alcohol syndrome, published last year in the Lancet Global Health.2 The FASD estimate for Italy was the result of a meta-analysis of 2 empirical studies that used active-case ascertainment (the criterion standard for obtaining the prevalence of FASD), random selection of schools from large school districts, an Institute of Medicine–endorsed diagnostic system, and the most experienced dysmorphologists in the world with respect to the diagnosis of FASD and screened a total of 1519 children.3,4 Indeed, both of these studies determined the population-based prevalence of FASD in 2 different regions: 1 in central Italy3 and the other in the Lazio region.4 Estimating the prevalence of FASD is challenging for many reasons (for example, limited diagnostic capacity, lack of a universal diagnostic approach and definitions, and the immense costs that are involved in conducting such comprehensive studies). Therefore, only a few countries in the world have such robust and properly conducted population-based FASD prevalence studies as Italy has.