Hearing assistive technologies in developing countries: Background, achievements, challenges.

PURPOSE: The burden of hearing impairment and disability is substantial in the developing world. This review outlines the associated need for amplification devices in low and medium income countries and some of the initiatives that have been taken to improve access to such devices, particularly hearing aids. The main observed barriers to access are listed and possible ways to improve access are considered. METHODS: Prevalence estimates for disabling hearing impairment are reviewed and a number of national and international examples of initiatives to facilitate use of hearing assistive devices in low and medium income countries are provided. Technologies that are potentially appropriate for hearing instruments in developing countries are suggested, as well as fitting programs that are more likely to be maintained over the long term. RESULTS: Challenges to successful hearing instrument fitting in low and medium income countries are many. However, some programs point the way to improved access to such devices. Successful hearing aid fitting programs in developing countries have typically combined appropriate technology with a sustainable local support base. CONCLUSIONS: With a rising middle class in many developing countries, advances in technology, and ongoing training programs for those involved in amplification fitting, hearing device usage rates may eventually reach parity with those in developed economies. IMPLICATIONS FOR REHABILITATION: The historical development of affordable hearing device fitting provision in low and middle income countries is outlined. Three key barriers to widespread access to hearing device provision in many low and middle income countries (LMICs) are identified: lack of trained personnel, the high cost of many existing devices marketed in LMICs and limited public awareness of the benefits of hearing assistive technologies. Examples of programs that have sought to overcome these barriers in LMICs are given and may influence the ways in which future hearing health care is provided