A theory of coverage rate differences for hearing aids around the world based on correlational observation and analysis.

Objective: Our objective was to ascertain likely reasons for explaining variation in coverage rates for hearing aids (HAs) among various countries around the world.

Design: A retrospective analysis of past coverage rates and their association to demographic and economic variables of apriori logical consideration.

Study sample: Data was obtained on macroeconomic conditions from 37 countries in the OECD and estimated coverage rates for HAs using recent actual sales data.

Results: Two variables were identified with a very strong correlation (R = 0.97, R² = 0.95) to coverage rates. The first variable was the level of subsidy provided for the citizens to obtain HAs. The second variable was the GNI/capita which reflects the income available to citizens to make the purchase of HAs.

Conclusion: In countries where subsidy for HAs are made available through either public or private health service/insurance, an increase in coverage rates is likely to occur. The effect of subsidy is likely to surpass any effect of OTC HAs that has been demonstrated to date. Where and when feasible, subsidy presence and encouraging income generation among able citizens of a country should be sought in tandem - a complex interplay of improving coverage rates for HAs with economics.