title: Childhood disability and socio-economic circumstances in low and middle income countries: systematic review.
abstract: BACKGROUND
  The majority of children with disability live in low and middle income (LAMI) countries. Although a number of important reviews of childhood disability in LAMI countries have been published, these have not, to our knowledge, addressed the association between childhood disability and the home socio-economic circumstances (SEC). The objective of this study is to establish the current state of knowledge on the SECs of children with disability and their households in LAMI countries through a systematic review and quality assessment of existing research.
  
  
  METHODS
  Electronic databases (MEDLINE; EMBASE; PUBMED; Web of Knowledge; PsycInfo; ASSIA; Virtual Health Library; POPLINE; Google scholar) were searched using terms specific to childhood disability and SECs in LAMI countries. Publications from organisations including the World Bank, UNICEF, International Monetary Fund were searched for. Primary studies and reviews from 1990 onwards were included. Studies were assessed for inclusion, categorisation and quality by 2 researchers.
  
  
  RESULTS
  24 primary studies and 13 reviews were identified. Evidence from the available literature on the association between childhood disability and SECs was inconsistent and inconclusive. Potential mechanisms by which poverty and low household SEC may be both a cause and consequence of disability are outlined in the reviews and the qualitative studies. The association of poor SECs with learning disability and behaviour problems was the most consistent finding and these studies had low/medium risk of bias. Where overall disability was the outcome of interest, findings were divergent and many studies had a high/medium risk of bias. Qualitative studies were methodologically weak.
  
  
  CONCLUSIONS
  This review indicates that, despite socially and biologically plausible mechanisms underlying the association of low household SEC with childhood disability in LAMI countries, the empirical evidence from quantitative studies is inconsistent and contradictory. There is evidence for a bidirectional association of low household SEC and disability and longitudinal data is needed to clarify the nature of this association.
authors.affiliation: Health Sciences Research Institute, Warwick Medical School, University of Warwick, Coventry, (CV4 7AL), UK. d.e.simkiss@warwick.ac.uk
authors.forename: Douglas E
authors.initials: DE
authors.lastname: Simkiss
authors.forename: Clare M
authors.initials: CM
authors.lastname: Blackburn
authors.forename: Felix O
authors.initials: FO
authors.lastname: Mukoro
authors.forename: Janet M
authors.initials: JM
authors.lastname: Read
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Spencer
mesh_terms: D002648:Child; D002657:Child Development; D003906:Developing Countries; D004185:Disability Evaluation; D019988:Children with Disabilities / Q000534:rehabilitation* / Q000706:statistics & numerical data; D014943:Global Health; D006801:Humans; D012959:Socioeconomic Factors