title: The Use of Key Informant Method for Identifying Children with Blindness and Severe Visual Impairment in Developing Countries.
abstract: An estimated 19 million children are visually impaired; of these, 1.4 million are irreversibly blind. A key challenge is to identify them early in life to benefit maximally from visual rehabilitation, and/or treatment. This aggregative review and structured literature analysis summarizes evidence of what it is about the key informant (KI) approach that works to identify children with blindness or severe visual impairment (B/SVI) in the community (for whom, to what extent, in what circumstances, in what respect, how and why).
  
  
  
  Peer-reviewed (PubMed, hand search) and grey literature (Google, World Health Organization website, academic theses, direct requests) were included, and methods and criteria used for identification, productivity (number of children referred per KI), accuracy of referrals (positive predictive value, PPV), age of children with B/SVI, KI definition, sex, information about cost and comparisons aggregated.
  
  
  
  We included 31 documents describing 22 unique KI programs. Mostly KIs identified children with B/SVI in 1-3 weeks, i.e. "campaign mode." In 60%, KIs were community volunteers, others formal health sector workers (FHSW). Around 0.02-1.56 children per KI (median = 0.25) were successfully recruited. PPV ranged from 12 to 66%. In two studies comparing FHSWs and community KIs, the latter were 8 and 10 times more productive.
  
  
  
  KIs working in campaign mode may provide an effective approach to identifying children with B/SVI in communities. Including identification of ocular problems and/or other impairments has been recommended. Research on factors that influence effectiveness and on whether KIs continue to contribute could inform programs.
authors.affiliation: a Independent consultant.
authors.forename: Rènée
authors.initials: R
authors.lastname: du Toit
authors.affiliation: b Kilimanjaro Centre for Community Ophthalmology , UCT Division of Ophthalmology, Groote Schuur Hospital , Cape Town , South Africa.
authors.forename: Paul
authors.initials: P
authors.lastname: Courtright
authors.affiliation: b Kilimanjaro Centre for Community Ophthalmology , UCT Division of Ophthalmology, Groote Schuur Hospital , Cape Town , South Africa.
authors.forename: Susan
authors.initials: S
authors.lastname: Lewallen
mesh_terms: D001766:Blindness / Q000175:diagnosis; D002648:Child; D002662:Child Health Services / Q000458:organization & administration; D003150:Community Health Workers; D003906:Developing Countries; D006801:Humans; D015397:Program Evaluation; D019035:Rural Health Services / Q000458:organization & administration; D014786:Vision Disorders / Q000175:diagnosis*; D019987:Persons with Visual Disabilities
keywords: Blind; childhood blindness; children; community volunteers; effectiveness; health workers; identify; key informant; screening; visually impaired