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Published on: July 9, 2016
The Use of Key Informant Method for Identifying Children with Blindness and Severe Visual Impairment in Developing
Rènée du Toit1, Paul Courtright2, Susan Lewallen2
1a Independent consultant.
Insights
The key informant (KI) approach effectively identifies children with blindness or severe visual impairment (B/SVI) in communities, especially when KIs work in campaign mode. Further research is recommended to optimize this identification strategy.
Area of Science:
- Public Health
- Ophthalmology
- Global Health
Background:
- An estimated 19 million children globally experience visual impairment, with 1.4 million suffering irreversible blindness.
- Early identification of blindness or severe visual impairment (B/SVI) in children is crucial for effective visual rehabilitation and treatment.
- The key informant (KI) approach is a community-based strategy for identifying children with B/SVI.
Purpose of the Study:
- To review and analyze evidence on the effectiveness of the key informant (KI) approach in identifying children with B/SVI in community settings.
- To understand the factors influencing the success of KI programs, including who, to what extent, in what circumstances, and how they work.
- To summarize evidence regarding the productivity and accuracy of the KI approach for B/SVI identification.
Main Methods:
- An aggregative review and structured literature analysis of peer-reviewed and grey literature were conducted.
- Included studies described unique KI programs, and data on identification methods, productivity, accuracy, and cost were aggregated.
- Literature searches included PubMed, Google, WHO website, theses, and direct requests.
Main Results:
- 31 documents detailing 22 unique KI programs were analyzed.
- KI programs, often run in "campaign mode" over 1-3 weeks, utilized community volunteers or formal health sector workers.
- Community KIs demonstrated higher productivity (8-10 times) compared to formal health sector workers, with positive predictive values ranging from 12% to 66%.
Conclusions:
- The key informant (KI) approach, particularly in campaign mode, appears effective for identifying children with B/SVI in communities.
- Recommendations include expanding KI identification to include other ocular and general impairments.
- Further research is needed to understand factors influencing KI program effectiveness and long-term contributions.
Purpose:
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).
Methods:
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.
Results:
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.
Conclusion:
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.
