title: Hyperopia: a meta-analysis of prevalence and a review of associated factors among school-aged children.
abstract: BACKGROUND
  Studies show great variability in the prevalence of hyperopia among children. This study aimed to synthesize the existing knowledge about hyperopia prevalence and its associated factors in school children and to explore the reasons for this variability.
  
  
  METHODS
  This systematic review followed PRISMA guidelines. Searching several international databases, the review included population- or school-based studies assessing hyperopia through cycloplegic autorefraction or cycloplegic retinoscopy. Meta-analysis of hyperopia prevalence was performed following MOOSE guidelines and using the random effects model.
  
  
  RESULTS
  The review included 40 cross-sectional studies. The prevalence of hyperopia ranged from 8.4% at age six, 2-3% from 9 to 14 years and approximately 1% at 15 years. With regard to associated factors, age has an inverse association with hyperopia. The frequency of hyperopia is higher among White children and those who live in rural areas. There is no consensus about the association between hyperopia and gender, family income and parental schooling.
  
  
  CONCLUSIONS
  Future studies should use standardized methods to classify hyperopia and sufficient sample size when evaluating age-specific prevalence. Furthermore, it is necessary to deepen the understanding about the interactions among hyperopic refractive error and accommodative and binocular functions as a way of identifying groups of hyperopic children at risk of developing visual, academic and even cognitive function sequelae.
authors.affiliation: Department of Specialized Medicine - Ophthalmology, Federal University of Pelotas, Rua Marechal Deodoro, 1160, Centro, 96020-220, Pelotas, RS, Brazil. vicastagno@hotmail.com.
authors.forename: Victor Delpizzo
authors.initials: VD
authors.lastname: Castagno
authors.affiliation: Department of Social Medicine, Rua Marechal Deodoro, 1160, Centro, 96020-220, Pelotas, RS, Brazil. anaclaudia.fassa@gmail.com.
authors.forename: Anaclaudia Gastal
authors.initials: AG
authors.lastname: Fassa
authors.affiliation: Department of Social Medicine, Federal University of Pelotas, Avenida Duque de Caxias, 250, Fragata, 96001-970, Pelotas, RS, Brazil. mvcarret@hotmail.com.
authors.forename: Maria Laura Vidal
authors.initials: ML
authors.lastname: Carret
authors.affiliation: Department of Specialized Medicine - Ophthalmology, Federal University of Pelotas, Rua Marechal Deodoro, 1160, Centro, 96020-220, Pelotas, RS, Brazil. mapvilela@gmail.com.
authors.forename: Manuel Augusto Pereira
authors.initials: MA
authors.lastname: Vilela
authors.affiliation: Department of Social Medicine, Federal University of Pelotas, Avenida Duque de Caxias, 250, Fragata, 96001-970, Pelotas, RS, Brazil. rodrigodalke@gmail.com.
authors.forename: Rodrigo Dalke
authors.initials: RD
authors.lastname: Meucci
mesh_terms: D000293:Adolescent; D017677:Age Distribution; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D006801:Humans; D006956:Hyperopia / Q000453:epidemiology*; D015995:Prevalence; D012307:Risk Factors; D017678:Sex Distribution