Diagnostic accuracy of non‐specialist versus specialist health workers in diagnosing hearing loss and ear disease in Malawi

Hearing loss characteristics and cerumen management efficacy in low-income South African communities: a cross-sectional study

AIM

To describe the prevalence and characteristics of hearing loss in a self-referred adult cohort in low-income South African communities and to evaluate the effectiveness of a cerumen management protocol within a community-based service setting.

BACKGROUND

Hearing loss affects 1.5 billion people globally, with a disproportionate impact on individuals in low- and middle-income countries (LMICs) and the elderly, often attributed to age-related factors and cerumen impaction. Despite the high prevalence, access to ear and hearing care remains challenging, particularly in LMICs, such as Africa.

METHODS

A total of 227 participants aged 43-102 were recruited from two community centres in low-income South African communities for hearing evaluation and cerumen management for those with cerumen impaction. A cross-sectional, predominantly quantitative approach was used.

FINDINGS

Video otoscopy of 448 ears revealed normal findings in 57.9%, cerumen impaction in 29.1%, and other abnormalities in 1.3%. The prevalence of confirmed hearing loss was 97.8%, primarily mild (45.8%), and sensorineural hearing loss (SNHL) was the most common (55.3%). Cerumen impaction accompanied hearing loss in 28.4% of cases. Post-treatment, 50.9% of participants with cerumen impaction showed normal otoscopy results, with mean hearing improvements of 16.2 dB (±17.9 SD) in the left ears and 15.8 dB (±17.2 SD) in the right ears, though overall significance was limited.

CONCLUSION

The high prevalence of hearing loss and cerumen impaction in low-income communities emphasizes the importance of ear care in primary healthcare (PHC) settings, especially for the elderly. Effective community-based cerumen management highlights the potential of integrating community resources and task-shifting strategies for cost-effective ear care in resource-limited settings.

Ten years of ear, nose and throat (ENT) services in Southern Africa: a scoping review

BACKGROUND

While ear, nose, and throat (ENT) diseases are a substantial threat to global health, comprehensive reviews of ENT services in Southern Africa remain scarce.

OBJECTIVE

This scoping review provides a decade-long overview of ENT services in Southern Africa and identifies gaps in healthcare provision. From the current literature, we hope to provide evidence-based recommendations to mitigate the challenges faced by the resource-limited ENT service.

DATA SOURCES

PubMed, Web of Science, EBSCOhost, Cochrane Library, Cochrane Library, and Scopus.

REVIEW METHODS

On several databases, we conducted a comprehensive literature search on both quantitative and qualitative studies on ENT services in Southern Africa, published between 1 January 2014 and 27 February 2024. The extracted data from the analyzed studies was summarized into themes.

RESULTS

Four themes in the fourteen studies included in the final analysis described the existing ENT services in Southern Africa: 1. Workforce scarcity and knowledge inadequacies, 2. Deficiencies in ENT infrastructure, equipment, and medication, 3. Inadequate ENT disease screening, management, and rehabilitation and 4. A lack of telehealth technology.

CONCLUSION

The Southern African ENT health service faces many disease screening, treatment, and rehabilitation challenges, including critical shortages of workforce, equipment, and medication. These challenges, impeding patient access to ENT healthcare, could be effectively addressed by implementing deliberate policies to train a larger workforce, increase ENT funding for equipment and medication, promote telehealth, and reduce the patient cost of care.

Basic ENT training for enhanced healthcare worker knowledge, attitudes and practices in a resource-limited setting: a pre-post and post-post cross-sectional study

INTRODUCTION

Diagnostic errors in ear, nose and throat (ENT) diseases are prevalent among healthcare workers (HCWs) in resource-limited settings, yet comprehensive data that describe HCW knowledge, attitudes and practices (KAP) regarding ENT disease management remains scarce. Further, the impact of basic ENT training on HCW KAP in such settings is largely undetermined.

OBJECTIVE

We assessed HCW KAP before and after basic training in ENT disease management.

METHODS

This questionnaire-based pre-post-test cross-sectional survey employed HCW training in public hospitals in a resource-limited setting. We conducted a 2-day training, preceded by a pretraining survey, followed by immediate and 5-month post-training assessments using a prevalidated questionnaire. 416 HCWs participated and were selected through probability-proportionate-to-size random sampling. Wilcoxon matched-pairs signed-rank and Kruskal-Wallis tests were used to assess pre-post training KAP variations.

RESULTS

At baseline, the median (IQR) percentage knowledge scores for HCWs in general ENT, ear, sinonasal and head and neck disease management were 60 (40), 55 (18), 58.3 (25) and 56 (22.6), respectively. Only 33.8% (133/394) of HCWs had access to an otoscope, 25.5% (101/396) to a headlight and 12.1% (48/397) to a nasal speculum. While 99.2% (390/393) of HCWs considered ENT important, 57.8% (226/391) of them lacked the confidence to correctly diagnose and manage most ENT conditions. At the immediate post-training assessment, HCWs' median knowledge scores increased by 20%, 18%, 25% and 33% for general ENT, ear, sinonasal and head and neck disease management, respectively (p<0.001). Further, the proportions of HCWs consistently performing otoscopy and using ENT guidelines increased from 15.1% (43/284) and 13.8% (48/282) to 35.5 (44/124) and 23.9% (27/113) 5 months post-training.

CONCLUSIONS

This study underscores the critical need for continuous medical education (CME) to address knowledge gaps and improve HCW attitudes and practices. The findings provide valuable insights for policymakers aiming to enhance ENT healthcare delivery in resource-limited settings.

"Us versus Them": is the voice of the community heard when planning communication screening programmes for preschoolers?

OBJECTIVES

Community consultation is necessary to ensure the uptake and use of community-based screening intervention to detect early childhood disabilities, as its absence can result in poor service acceptance and usage. To document stakeholders' perspectives regarding planning a community-based communication disorder (an impairment in the ability to receive, send, process and comprehend concepts or verbal, non-verbal and graphic symbol systems) screening programmes for pre-schoolers.

STUDY DESIGN

This qualitative research design used purposive and random sampling to recruit 46 participants from eThekwini Municipality, South Africa. These stakeholders consisted of caregivers/parents of children who underwent screening for communication disorders, People who are Deaf, their parents, early childhood development practitioners, health professionals and government officials involved with children with disabilities. All participants were adults aged between 19 and 79 years, with an average age of 39.7 years.

METHODS

Data was collected through focus group discussions and individual interviews, which were thematically analysed.

RESULTS

The four emergent themes were screening approaches, methods, location and personnel. Service users expected greater access to screening and reliable tests to identify problems by trained personnel at sites within the community. Service providers preferred a targeted approach to screening with parental input. Task shifting and sharing were seen as a solution to address staff shortages and provide services at health facilities, as resource constraints made it challenging to provide outreach services.

CONCLUSION

Stakeholder engagement revealed diverging views between service users and providers, with implications for programme provision and uptake. There is a need for ongoing, inclusive discussion to ensure consensus during the planning stage, in order to render services that address issues of equity and accessibility for people with disabilities in marginalised communities.

Examining Diagnostic Errors in the Field of Otorhinolaryngology within the Challenging Landscape of Limited-Resource Healthcare

Diagnostic accuracy is vital in otorhinolaryngology for effective patient care, yet diagnostic mismatches between non-otorhinolaryngology clinicians and ENT specialists can occur. However, studies investigating such mismatches in low-resource healthcare environments are limited. This study aims to analyze diagnostic mismatches in otorhinolaryngology within a low-resource healthcare environment. A publicly available dataset assessing diagnostic outcomes from non-otorhinolaryngology clinicians and ENT specialists was analyzed. The dataset included demographic characteristics, referral diagnoses, and final ENT specialist diagnoses. Descriptive statistics and appropriate statistical tests were employed to assess the prevalence of diagnostic mismatches and associated factors. The analysis comprised 1544 cases. The prevalence of diagnostic mismatches between non-otorhinolaryngology clinicians and ENT specialists was 67.4%. Certain specific ENT diseases demonstrated higher frequencies of diagnostic mismatches. Factors such as mismatch in the diagnosis and compliance of patient were found to influence the occurrence of diagnostic mismatches. This study highlights the presence of diagnostic mismatches in otorhinolaryngology within a low-resource healthcare environment. The prevalence of these mismatches underscores the need for improved diagnostic practices in such settings. Factors contributing to diagnostic mismatches should be further explored to develop strategies for enhancing diagnostic accuracy and reducing diagnostic errors in otorhinolaryngology.

Service delivery approaches related to hearing aids in low- and middle-income countries or resource-limited settings: A systematic scoping review

Hearing loss is an important global public health issue which can be alleviated through treatment with hearing aids. However, most people who would benefit from hearing aids do not receive them, in part due to challenges in accessing hearing aids and related services, which are most salient in low- and middle-income countries (LMIC) and other resource-limited settings. Innovative approaches for hearing aid service delivery can overcome many of the challenges related to access, including that of limited human resources trained to provide ear and hearing care. The purpose of this systematic scoping review is to synthesize evidence on service delivery approaches for hearing aid provision in LMIC and resource-limited settings. We searched 3 databases (PubMed, Scopus, Ovid MEDLINE) for peer-reviewed articles from 2000 to 2022 that focused on service delivery approaches related to hearing aids in LMIC or resource-limited settings. Fifteen peer-reviewed articles were included, which described hospital-based (3 studies), large-scale donation program (1 studies), community-based (7 studies), and remote (telehealth; 4 studies) service delivery approaches. Key findings are that hearing aid services can be successfully delivered in hospital- and community-based settings, and remotely, and that both qualified hearing care providers and trained non-specialists can provide quality hearing aid services. Service delivery approaches focused on community-based and remote care, and task sharing among qualified hearing care providers and trained non-specialists can likely improve access to hearing aids worldwide, thereby reducing the burden of untreated hearing loss.

Mobile Health Hearing Aid Acclimatization and Support Program in Low-Income Communities: Feasibility Study

BACKGROUND

The most common management option for hearing loss is hearing aids. In addition to devices, patients require information and support, including maintenance and troubleshooting. Mobile health (mHealth) technologies can support hearing aid management, acclimatization, and use. This study developed an mHealth acclimatization and support program for first-time hearing aid users and subsequently implemented and pilot-tested the feasibility of the program. The program was facilitated by community health workers (CHWs) in low-income communities in South Africa.

OBJECTIVE

This study aimed to evaluate the feasibility of an mHealth acclimatization and support program supported by CHWs in low-income communities.

METHODS

An application-based acclimatization and support was adapted and translated for use in low- and middle-income countries. This program was delivered in the form of 20 different voice notes accompanied by graphical illustrations via WhatsApp or 20 different SMS text messages. The program was provided to first-time hearing aid users immediately after a community-based hearing aid fitting in March 2021 in 2 low-income communities in the Western Cape, South Africa. The 20 messages were sent over a period of 45 days. Participants were contacted telephonically on days 8, 20, and 43 of the program and via open-ended paper-based questionnaires translated to isiXhosa 45 days and 6 months after the program started to obtain information on their experiences, perceptions, and accessibility of the program. Their responses were analyzed using inductive thematic analysis.

RESULTS

A total of 19 participants fitted with hearing aids received the mHealth acclimatization and support program. Most participants (15/19, 79%) received the program via WhatsApp, with 21% (4/19) of them receiving it via SMS text message. Participants described the program as helpful, supportive, informative, sufficient, and clear at both follow-ups. A total of 14 participants reported that they were still using their hearing aids at the 6-month follow-up. Three participants indicated that not all their questions about hearing aids were answered, and 5 others had minor hearing aid issues. This included feedback (n=1), battery performance (n=1), physical fit (n=2), and issues with hearing aid accessories (n=1). However, CHWs successfully addressed all these issues. There were no notable differences in responses between the participants who received the program via WhatsApp compared with those who received it through SMS text message. Most participants receiving WhatsApp messages reported that the voice notes were easier to understand, but the graphical illustrations supplemented the voice notes well.

CONCLUSIONS

An mHealth acclimatization and support program is feasible and potentially assists hearing aid acclimatization and use for first-time users in low-income communities. Scalable mHealth support options can facilitate increased access and improve outcomes of hearing care.

Combined hearing and vision screening programs: A scoping review

Background and aim

The World Health Organization (WHO) estimates that 1.5 billion and 2.2 billion people have hearing and vision impairment, respectively. The burden of these non-communicable diseases is highest in low- and middle-income countries due to a lack of services and health professionals. The WHO has recommended universal health coverage and integrated service delivery to improve ear and eye care services. This scoping review describes the evidence for combined hearing and vision screening programs.

Method

A keyword search of three electronic databases, namely Scopus, MEDLINE (PubMed), and Web of Science, was conducted, resulting in 219 results. After removing duplicates and screening based on eligibility criteria, data were extracted from 19 included studies. The Joanna Briggs Institute Reviewer Manual and the Preferred Reporting Items for Systematic Reviews and Meta-analyzes (PRISMA) Extension for Scoping Reviews were followed. A narrative synthesis was conducted.

Results

Most studies (63.2%) were from high-income countries, with 31.6% from middle-income and 5.2% from low-income countries. The majority of studies (78.9%) involved children and the four studies reporting on adults all included adults above 50 years of age. Vision screening was most commonly performed with the "Tumbling E" and "Snellen Chart," while hearing was typically screened using pure tone audiometry. Studies reported referral rates as the most common outcome with sensitivity and specificity rates not reported in any included articles. Reported benefits of combined vision and hearing screenings included earlier detection of vision and hearing difficulties to support functioning and quality of life as well as resource sharing for reduced costs. Challenges to combined screening included ineffective follow-up systems, management of test equipment, and monitoring of screening personnel.

Conclusions

There is limited research evidence for combined hearing and vision screening programs. Although potential benefits are demonstrated, especially for mHealth-supported programs in communities, more feasibility and implementation research are required, particularly in low- and middle-income countries and across all age groups. Developing universal, standardized reporting guidelines for combined sensory screening programs is recommended to enhance the standardization and effectiveness of combined sensory screening programs.

A longitudinal community-based ototoxicity monitoring programme and treatment effects for drug-resistant tuberculosis treatment, Western Cape

Background

South Africa has a high burden of drug-resistant tuberculosis (DRTB) and until recently, ototoxic aminoglycosides were predominant in treatment regimens. Community-based ototoxicity monitoring programmes (OMPs) have been implemented for early detection of hearing loss and increased patient access.

Objectives

A longitudinal study was conducted to describe the service delivery characteristics of a community-based OMP for DRTB patients facilitated by CHWs as well as observed ototoxic hearing loss in this population.

Method

A descriptive retrospective record review of longitudinal ototoxicity monitoring of 194 DRTB patients undergoing treatment at community-based clinics in the city of Cape Town between 2013 and 2017.

Results

Follow-up rates between consecutive monitoring assessments reached as high as 80.6% for patients assessed by CHWs. Few patients (14.2% – 32.6%) were assessed with the regularity (≥ 6 assessments) and frequency required for effective ototoxicity monitoring, with assessments conducted, on average, every 53.4–64.3 days. Following DRTB treatment, 51.5% of patients presented with a significant ototoxic shift meeting one or more of the American Speech-Language-Hearing Association (ASHA) criteria. Deterioration in hearing thresholds was bilateral and most pronounced at high frequencies (4 kHz – 8 kHz). The presence of pre-existing hearing loss, human immunodeficiency virus co-infection and a history of noise exposure were significant predictors of ototoxicity in patients.

Conclusion

DRTB treatment with kanamycin resulted in significant deterioration of hearing longitudinally, predominantly at high frequencies. With ongoing training and supportive supervision, CHWs can facilitate community-based ototoxicity monitoring of DRTB patients. Current protocols and guidelines may require reassessment for appropriate community-based ototoxicity monitoring.

Prevalence and characteristics of hearing and vision loss in preschool children from low income South African communities: results of a screening program of 10,390 children

BACKGROUND

The majority of children with sensory impairments live in low- and middle-income countries. More studies of hearing and vision impairment prevalence are needed, in order to generate more accurate estimates of trends in sensory impairments. This study aimed to estimate the prevalence and describe the characteristics of hearing and vision loss among preschool children (4-7 years) in an underserved South African community following community-based mobile health (mHealth) supported hearing and vision services.

METHODS

A screening program of sensory impairments was undertaken of children attending preschools in the communities of Khayelitsha and Mitchell's Plain, Cape Town, from September 2017 until June 2019. Hearing and vision screening were done by trained community health workers using mHealth technology. Children who failed hearing and vision screening were seen for follow-up assessments at their preschools. Follow-up assessments were conducted using smartphones that host point-of-care validated and calibrated hearing and vision testing applications (hearTest app, hearX Group, South Africa and PeekAcuity app, Peek Vision, United Kingdom). Descriptive statistical analysis and logistic regression analysis were conducted after extracting data from a secure cloud-based server (mHealth Studio, hearX Group) to Microsoft Excel (2016).

RESULTS

A total of 10,390 children were screened at 298 preschools over 22 months. Of the children screened, 5.6 and 4.4% of children failed hearing and vision screening respectively. Community-based follow-up hearing tests were done at the preschools on 88.5% (514) of children of whom 240 children (54.2% female) presented with hearing loss. A preschool-based follow-up vision test was done on 400 children (88.1%). A total of 232 children (46.1% female) had a vision impairment, and a further 32 children passed the test but had obvious signs of ocular morbidity. Logistic regression analysis found that age was a significant predictor of vision loss (p < 0.05), but not for hearing loss (p = 0.06). Gender was not a significant predictor of hearing (p = 0.22) or vision loss (p = 0.20).

CONCLUSIONS

Hearing loss is prevalent in at least 22 per 1000 and vision loss in at least 23 per 1000 preschool children in an underserved South African community. Timely identification of sensory losses can be facilitated through community-based hearing and vision services supported by mHealth technology.

The Use of Tele Practice in Assessment of Middle Ear Function in Adults Living with HIV During the COVID-19 Pandemic

Coronavirus disease (COVID-19) pandemic is the latest threat to global health that causes severe acute respiratory syndrome (SARS). Tele-practice has inadvertently sprung to the forefront to become a common practice amongst healthcare providers during COVID-19. Limited evidence exists on the use of tele-practice in assessing middle ear function in adults living with HIV during the COVID-19 pandemic. The aims of this study were to investigate the use of tele-practice for assessment of middle ear function in adults with HIV during the COVID-19 pandemic. A quantitative observational, cross-sectional design was adopted. A total of 134 adults diagnosed with HIV were purposively selected from the HIV clinic. An audiology researcher, in the role of site-facilitator, captured video otoscopic images of the tympanic membrane using a video otoscopy for all participants through asynchronous tele-practice. All captured images were sent to two independent otorhinolaryngologists for diagnosis. Findings of this study indicated that tele-practice can be used to assess middle ear function in adults living with HIV during COVID-19 pandemic. When asynchronous tele-practice was used, there was a moderate diagnostic agreement (k = 0.58) between the two otorhinolaryngologists on abnormality versus normality, but poor agreement (k = 0.15) on the nature of abnormality (e.g. OME vs CSOM). Current findings highlight the urgent need for a widespread use of tele-practice during the continued clinical follow up and management of adults living with HIV, and the implementation of tele-practice, particularly in low- and middle-income countries (LMICs) where capacity versus demand challenges related to ear and hearing care continue to exists.

Training, supervision and performance of Community Health Workers in the delivery of ear and hearing care to 321 community members in rural Uganda

OBJECTIVES

Community Health Workers are one way to address the shortage of ear and hearing care specialists in low-resource settings. However, there are few reports evaluating training and service delivery by Community Health Workers.

DESIGN, SETTING AND PARTICIPANTS

We trained 13 Community Health Workers in primary ear and hearing care in Mukono District, Uganda. Community Health Workers attended a two-day training workshop and received remote supervision thereafter during service delivery in the community. An ear camp was held at the local health centre every two months, where a local ENT specialist could assess referred cases.

MAIN OUTCOME MEASURES

Clinical and diagnostic skills and decision-making were assessed using an Objective Structured Clinical Examination, with scores recorded at baseline and six months. Service delivery was evaluated by analysing the following: (i) number of individuals evaluated; (ii) treatments delivered; (iii) cases referred for specialist opinion; (iv) proportion of appropriately referred cases; and (v) agreement between Community Health Worker and specialist diagnosis.

RESULTS

Observed Structured Clinical Examination scores were high and stable for six months. 312 individuals were screened in the community by the Community Health Workers, with 298 classified as having an abnormality. Care was delivered in the community to 167 of these, and the remaining 131 referred to the ear camp. Diagnostic agreement was 39%, but 98% of referrals were deemed "appropriate" by the ENT specialist. 27 individuals self-presented to the ear camp without prior assessment by a Community Health Worker, and 97% of these were deemed appropriate.

CONCLUSION

Trained Community Health Workers can play an important role in delivering ear and hearing services. Future work should look to explore this model in other contexts and/or compare it to other models of service delivery.

Mhealth hearing screening for children by non-specialist health workers in communities

OBJECTIVES

To compare outcomes of a community-based hearing screening programme using smartphone screening audiometry operated by specialist (School Health Nurses - SHNs) and non-specialist health workers (Community Health Workers - CHWs) in school children.

DESIGN

This study used a two-group comparison of screening outcomes as conducted by SHNs and CHWs using smartphone screening for children in communities.

STUDY SAMPLE

The study included 71 CHWs and 21 SHNs who conducted community-based hearing screening on 6805 children. One thousand one hundred and fifteen hearing screening tests were conducted by the CHWs and 5690 tests by the SHNs.

RESULTS

No significant difference in screening outcome was evident between CHWs and SHNs using a binomial logistic regression analysis considering age, test duration and noise levels as independent variables. Final screening result was significantly affected by age (p < 0.005), duration of test (p < 0.005) and noise levels exceeding at 1 kHz in at least one ear (p < 0.005). Test failure was associated with longer test duration (p < 0.005; B: 119.98; 95% CI: 112.65-127.30). CHWs had significantly (p < 0.005) longer test durations (68.70 s; 70 SD) in comparison to SHNs (55.85 s; 66.1 SD).

CONCLUSION

Low-cost mobile technologies with automated testing facilitated from user-friendly interfaces allow minimally trained persons to provide community-based screening comparable to specialised personnel.

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

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.

Field-testing of a rapid survey method to assess the prevalence and causes of hearing loss in Gao'an, Jiangxi province, China

BACKGROUND

The Rapid Assessment of Hearing Loss (RAHL) survey protocol aims to measure the prevalence and causes of hearing loss in a low cost and rapid manner, to inform planning of ear and hearing services. This paper reports on the first field-test of the RAHL in Gao'an County, Jiangxi Province, China. This study aimed to 1) To report on the feasibility of RAHL; 2) report on the estimated prevalence and causes of hearing loss in Gao'an.

METHODS

A cross-sectional population-based survey was conducted in September-October 2018. Forty-seven clusters in Gao'an County were selected using probability-proportionate-to-size sampling. Within clusters, compact segment sampling was conducted to select 30 people aged 50+. A questionnaire was completed covering sociodemographics, hearing health, and risk factors. Automated pure-tone audiometry was completed for all participants, using smartphone-based audiometry (hearTest), at 0.5, 1, 2, 4 kHz (kHz). All participants had their ears examined by an Ear Nose and Throat (ENT) doctor, using otoscopy, and probable causes of hearing loss assigned. Prevalence estimates were age and sex standardised to the Jiangxi population. Feasibility of a cluster size of 30 was examined by assessing the response rate, and the proportion of clusters completed in 1 day.

RESULTS

1344 of 1421 eligible participants completed the survey (94.6%). 100% of clusters were completed in 1 day. The survey was completed in 4.5 weeks. The prevalence of moderate or greater hearing loss (pure-tone average of 0.5, 1, 2, 4 kHz of > = 41dBHL in the better ear) was 16.3% (95% CI = 14.3, 18.5) and for any level of hearing loss (pure-tone average of > = 26dBHL in the better ear) the prevalence was 53.2% (95% CI = 49.2, 57.1). The majority of hearing loss was due to acquired sensorineural causes (91.7% left; 92.1% right). Overall 54.0% of the population aged 50+ (108,000 people) are in need of diagnostic audiology services, 3.4% were in need of wax removal (7000 people), and 4.8% were in need of surgical services (9500 people). Hearing aid coverage was 0.4%.

CONCLUSION

The RAHL survey protocol is feasible, demonstrated through the number of people examined per day, and the high response rate. The survey was completed in a much shorter period than previous all-age surveys in China. Some remaining challenges included assignment of causes of probable sensorineural loss. The data obtained from this survey can be used to scale-up hearing services in Gao'an.

Rationale and feasibility of a combined rapid assessment of avoidable blindness and hearing loss protocol

Purpose

This 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.

Methods

A 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.

Results

The 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.

Conclusion

The 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.

Rationale for a Rapid Methodology to Assess the Prevalence of Hearing Loss in Population-Based Surveys

Data on the prevalence and causes of hearing loss is lacking from many low and middle-income countries, in part, because all-age population-based surveys of hearing loss can be expensive and time consuming. Restricting samples to older adults would reduce the sample size required, as hearing loss is more prevalent in this group. Population-based surveys of hearing loss require clinicians to be involved in the data collection team and reducing the duration of the survey may help to minimise the impact on service delivery. The objective of this paper was to identify the optimal age-group for conduct of population-based surveys of hearing loss, balancing sample size efficiencies, and expected response rates with ability to make inferences to the all-age population. Methods: Between 2013–2014, two all aged population-based surveys of hearing loss were conducted in one district each of India and Cameroon. Secondary data analysis was conducted to determine the proportion of hearing loss (moderate or greater) in people aged 30+, 40+ and 50+. Poisson regression models were developed to predict the expected prevalence of hearing loss in the whole population, based on the prevalence in people aged 30+, 40+, and 50+, which was compared to the observed prevalence. The distribution of causes in these age groups was also compared to the all-age population. Sample sizes and response rates were estimated to assess which age cut-off is most rapid. Results: Of 160 people in India and 131 in Cameroon with moderate or greater hearing loss, over 70% were older than 50 in both settings. For people aged 30+ (90.6% India; 76.3% Cameroon), 40+ (81% India; 75% Cameroon) and 50+ (73% India; 73% Cameroon) the proportions were higher. Prediction based on Poisson distributed observations the predicted prevalence based on those aged 30+, 40+, and 50+ fell within the confidence intervals of the observed prevalence. The distribution of probable causes of hearing loss in the older age groups was statistically similar to the total population. Sample size calculations and an analysis of response rates suggested that a focus on those aged 50+ would minimise costs the most by reducing the survey duration. Conclusion: Restricting the age group included in surveys of hearing loss, in particular to people aged 50+, would still allow inferences to be made to the total population, and would mean that the required sample size would be smaller, thus reducing the duration of the survey and costs.