Prevention of blindness and deafness

Epidemiology and economic analysis

Countries are encouraged, with WHO technical support, to conduct random sample, population-based prevalence and cause surveys of deafness and hearing loss. The WHO Ear and Hearing Disorders- Survey Protocol offers a standardized tool for undertaking such population based surveys. It describes the methodology and provides a questionnaire for use.

Population based surveys to assess prevalence of hearing loss and its causes have been undertaken in:

  • Bangladesh
  • Brazil (Canoas)
  • China (Jiangsu, Sechuan, Guizhou, Jilin provinces)
  • Ecuador
  • India (Vellore)
  • Indonesia (Bandung)
  • Iran (Tehran)
  • Madagascar
  • Myanmar (Yangon)
  • Nigeria (Tana province)
  • Oman
  • Sri Lanka
  • Vietnam (Northern, Southern)

The screening protocol is currently being revised and the revised protocol is expected to be launched by end of 2016.

An economic analysis of sensory disabilities was undertaken in 2000 (see below).

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