Abstract
PurposeThis study has two main objectives: 1) to assess the value of combining the rapid assessment of avoidable blindness (RAAB) and the recently developed rapid assessment of hearing loss (RAHL) based on existing population-based data from Cameroon andIndia; 2) to test the feasibility of a combined RAAB-RAHL protocol.MethodsA secondary data analysis of population-based disability surveys in India and Cameroon (in 2013–2014) was conducted, focussing on people aged 50+. Hearing impairment (HI) was defined as pure tone average of ≥41dB (better ear).Visual impairment (VI) was defined as presenting visual acuity of <6/18 (better eye). The relationship between HI and VI was examined. The feasibility of a combined RAAB-RAHL survey was assessed within a RAHL conducted among adults aged 50+ in Malawi in 2018. Outcomes included: time taken, costs, number of people examined in a day, and qualitative feedback from participants and field teams.ResultsThe prevalence of combined VI and HI among people aged 50+ was 4.4% (95% confidence interval (CI) 3.0, 6.4) in India and 4.8% (95%CI 3.0, 8.0) in Cameroon. Among participants with VI, approximately a third in India (29.3%) and Cameroon (35.1%) also had HI. A quarter of participants in India (25.4%) and Cameroon (26.9%) who had HI also had VI. In Malawi, the total time taken to complete both RAAB and RAHL assessments was approximately 27 minutes per participant. It was feasible to complete 30 participants per day for a team of four people. The estimated cost of a combined RAAB-RAHL approach in comparison to two separate impairment surveys is up to 37% less depending on the method of combination.ConclusionThe substantial overlap between VI and HI supports a combined rapid survey of the two impairments. The pilot study of a combined RAAB-RAHL survey demonstrates feasibility and lower cost compared to conducting two standalone impairment surveys. A combined RAAB-RAHL approach could maximize limited resources to increase prevalence data for both vision and hearing impairment.
Highlights
The prevalence of visual impairment (VI) and hearing impairment (HI) tends to be higher in lowand middle-income countries (LMICs).[1, 4]
Evidence suggests that over 80% of blindness is experienced by those aged 50+, and that the distribution of the main causes of blindness in this age group are comparable to the all-age population.[7]
We conducted secondary analysis of datasets to explore the relationship between VI and HI in two LMICs and the potential value of combined rapid surveys
Summary
More than 250 million people have visual impairment (VI) and over 450 million have hearing impairment (HI).[1,2,3] The prevalence of VI and HI tends to be higher in lowand middle-income countries (LMICs).[1, 4] Over the 30 years, with ageing and global population growth, the number of people affected by both impairments is expected to rise–to 700 million (1 in 12 people) with VI and 900 million (1 in 10 people) with HI.[1, 3] Reliable data on needs and unmet needs for eye and ear care services are needed for planning purposes.The Rapid Assessment of Avoidable Blindness (RAAB), has been a successful approach to collecting population-based data on the prevalence and causes of blindness and VI in a lowcost and rapid manner.[5]. Evidence suggests that over 80% of blindness is experienced by those aged 50+, and that the distribution of the main causes of blindness in this age group are comparable to the all-age population.[7] focussing on this age group substantially reduces the sample size required to accurately estimate the prevalence, yet still generates data that can be used to plan eye care services for the total population. A simplified clinical protocol, using lowcost equipment, is used to test vision and examine eyes. This allows testing to be done relatively quickly in the participant’s home. The results from RAAB surveys can be compared over time and across settings
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
