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The key informant method: a novel means of ascertaining blind children in Bangladesh

Mohammad A Muhit1, Shaheen P Shah, Clare E Gilbert

  • 1International Centre for Eye Health, Clinical Research Unit, Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1 7HT. UK. Mohammad.Muhit@Lshtm.ac.uk

The British Journal of Ophthalmology
|April 14, 2007
PubMed

Insights

Trained local volunteers as key informants (KIs) effectively identified more children with severe visual impairment or blindness (SVI/BL) in Bangladesh. This novel approach yielded a more representative sample, including those with treatable conditions, compared to traditional methods.

Area of Science:

  • Ophthalmology
  • Public Health
  • Epidemiology

Background:

  • Traditional methods for identifying children with severe visual impairment or blindness (SVI/BL) primarily relied on special education data, potentially skewing population representation.
  • A novel approach using local volunteers as key informants (KIs) was developed to ascertain a more representative sample of SVI/BL children.

Purpose of the Study:

  • To compare the demographic characteristics and causes of blindness in children identified through the KI method versus other ascertainment strategies.
  • To evaluate the effectiveness of the KI approach in recruiting a broader and more representative population of SVI/BL children.

Main Methods:

  • A study was conducted across all 64 districts of Bangladesh to recruit children with SVI/BL.
  • Three case ascertainment methods were employed: schools for the blind (SpEdu), community-based rehabilitation (CBR) programs, and trained KIs.
  • Data collection utilized the standard WHO/PBL Eye Examination Record.

Main Results:

  • A total of 1935 children were recruited, with KIs identifying the majority (64.3%).
  • Children recruited by KIs were significantly more likely to be female, of pre-school age, from rural areas, and have multiple impairments compared to those in SpEdu.
  • The KI method demonstrated higher odds of ascertaining children with avoidable causes of SVI/BL compared to both SpEdu and CBR methods.

Conclusions:

  • The innovative KI approach facilitated one of the largest studies on SVI/BL children to date.
  • Key informants proved effective in rapidly recruiting a substantial number of children.
  • The findings suggest that the KI method yields a more representative sample of SVI/BL children within the community.
Abstract

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