Field test of the Rapid Assessment of Hearing Loss survey protocol in Ntcheu district, Malawi

Abstract

Objective: (1) To test the feasibility of the Rapid Assessment of Hearing Loss (RAHL) survey protocol in Malawi (Ntcheu); (2) To estimate the prevalence and probable causes of hearing loss (adults 50+).Design: Cross-sectional population-based survey.Study sample: Clusters (n = 38) were selected using probability-proportionate-to-size-sampling. Within each cluster, 30 people aged 50+ were selected using compact-segment-sampling. All participants completed smartphone-based audiometry (hearTest). Prevalence was estimated using WHO definitions (PTA of thresholds 0.5, 1, 2, 4 kHz in the better ear of >25 dB HL (any) and >40 dB HL (≥moderate)). Otoscopy and questionnaire were used to assess probable causes. Participants with hearing loss and/or ear disease were asked about care-seeking and barriers.Results: Four teams completed the survey in 24 days. 1080 of 1153 (93.7%) participants were examined. The median time to complete the protocol was 24 min/participant. Prevalence of hearing loss was 35.9% (95% CI = 31.6–40.2) (any level); and 10.0% (95% CI = 7.9–12.5) (≥moderate). The majority was classified as probable sensorineural. Nearly one third of people (30.9%) needed diagnostic audiology services and possible hearing aid fitting. Hearing aid coverage was <1%. Lack of perceived need was a key barrier.Conclusion: The RAHL is simple, fast and provides information about the magnitude and probable causes of hearing loss to plan services.