title: Worldwide Prevalence of Fetal Alcohol Spectrum Disorders: A Systematic Literature Review Including Meta-Analysis.
abstract: BACKGROUND
  Although fetal alcohol spectrum disorders (FASD) affect communities worldwide, little is known about its prevalence. The objective of this study was to provide an overview of the global FASD prevalence.
  
  
  METHODS
  We performed a search in multiple electronic bibliographic databases up to August 2015, supplemented with the ascendancy and descendancy approach. Studies were considered when published in English, included human participants, and reported empirical data on prevalence or incidence estimates of FASD. Raw prevalence estimates were transformed using the Freeman-Tukey double arcsine transformation so that the data followed an approximately normal distribution. Once the pooled prevalence estimates, 95% confidence intervals and prediction intervals were calculated based on multiple meta-analyses with transformed proportions using random effects models, these estimates were transformed back to regular prevalence rates. Heterogeneity was tested using Cochran's Q and described using the I(2) statistic.
  
  
  RESULTS
  Among studies that estimated prevalence in general population samples, considerable differences in prevalence rates between countries were found and therefore separate meta-analyses for country were conducted. Particularly high-prevalence rates were observed in South Africa for fetal alcohol syndrome (55.42 per 1,000), for alcohol-related neurodevelopmental disorder (20.25 per 1,000), and FASD (113.22 per 1,000), For partial fetal alcohol syndrome high rates were found in Croatia (43.01 per 1,000), Italy (36.89 per 1,000), and South Africa (28.29 per 1,000). In the case of alcohol-related birth defects, a prevalence of 10.82 per 1,000 was found in Australia. However, studies into FASD exhibited substantial heterogeneity, which could only partly be explained by moderators, most notably geography and descent, in meta-regressions. In addition, the moderators were confounded, making conclusions as to each moderator's relevance tentative at best.
  
  
  CONCLUSIONS
  The worldwide pooled prevalence estimates are higher than assumed so far, but this was largely explained by geography and descent. Furthermore, prevalence studies varied considerably in terms of used methodology and methodological quality. The pooled estimates must therefore be interpreted with caution and for future research it is highly recommended to report methodology in a more comprehensive way. Finally, clear guidelines on assessing FASD prevalence are urgently needed, and a first step toward these guidelines is presented.
authors.affiliation: Governor Kremers Centre, Maastricht University Medical Centre, Maastricht, the Netherlands.|Department of Work and Social Psychology, Maastricht University, Maastricht, the Netherlands.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Roozen
authors.affiliation: Department of Work and Social Psychology, Maastricht University, Maastricht, the Netherlands.|Faculty of Psychology and Education Science, Open University of the Netherlands, Heerlen, the Netherlands.
authors.forename: Gjalt-Jorn Y
authors.initials: GJ
authors.lastname: Peters
authors.affiliation: Governor Kremers Centre, Maastricht University Medical Centre, Maastricht, the Netherlands.|Department of Work and Social Psychology, Maastricht University, Maastricht, the Netherlands.
authors.forename: Gerjo
authors.initials: G
authors.lastname: Kok
authors.affiliation: Governor Kremers Centre, Maastricht University Medical Centre, Maastricht, the Netherlands.|Department of Health, Ethics & Society, Maastricht University, Maastricht, the Netherlands.
authors.forename: David
authors.initials: D
authors.lastname: Townend
authors.affiliation: Governor Kremers Centre, Maastricht University Medical Centre, Maastricht, the Netherlands.|Department of Obstretrics & Gynaecology, GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, the Netherlands.
authors.forename: Jan
authors.initials: J
authors.lastname: Nijhuis
authors.affiliation: Governor Kremers Centre, Maastricht University Medical Centre, Maastricht, the Netherlands.|Department of Genetics, Maastricht University Medical Centre, Maastricht, the Netherlands.
authors.forename: Leopold
authors.initials: L
authors.lastname: Curfs
mesh_terms: D001315:Australia / Q000453:epidemiology; D017523:Croatia / Q000453:epidemiology; D063647:Fetal Alcohol Spectrum Disorders / Q000453:epidemiology*; D014943:Global Health; D006801:Humans; D007558:Italy / Q000453:epidemiology; D015995:Prevalence; D013019:South Africa / Q000453:epidemiology
keywords: Epidemiology; Fetal Alcohol Spectrum Disorder(s); Meta-Analysis; Prevalence; Systematic Literature Review