The hearZA app–South Africa's national hearing test–was launched on World Hearing Day in March 2016. Within 24 hours of the launch, more than 3,000 people tested their hearing on iOS and Android versions of this South African English test that was developed and validated at the University of Pretoria. The quick, self-administered, digits-in-noise test provides a valuable indication of real-life hearing ability—the ability to understand speech in noise.
Our aim was to have a strategic public awareness tool for accurate detection of hearing loss that allows for personalized hearing health tracking, in-app decision support, and a referral network to link people to their closest hearing health providers. Only 10 percent of South African households have access to a landline, so employing a smartphone-based test with close to 80 percent household penetration was an obvious choice (Statistics South Africa, 2013 http://bit.ly/2g546ol; Ericsson, 2015). We also wanted to leverage a smartphone platform for all the additional possibilities it offers beyond detecting a hearing problem.
Public Awareness Tool
Smartphones are an integral part of modern day living, with health applications becoming central to their monitoring features. We wanted to capitalize on this trend and use it as primary and secondary approaches to increase awareness of healthy hearing.
To spread the hearing health message in mainstream media, we partnered with the largest mobile operator in South Africa as the main sponsor, along with other key players in the hearing industry. Each sponsor purchased test credits that ensure free testing is offered to every South African on the hearZA app. In return, sponsors get an in-app advertisement right before the test commences for their sponsorship. Every download offers three free hearing tests, after which in-app purchases are required.
We also invested in a strategic media campaign using the WHO's World Hearing Day as a springboard from which to get the message out to the broadest audience possible. We recorded four videos with local celebrities who were willing to serve as hearing health ambassadors taking the hearZA test. These were disseminated through various social media platforms. One video had over 250,000 views on Facebook.
The app also encourages sharing the hearing test through social media channels (with or without the score). Health messaging graphics for social media posts are provided as part of this sharing function (Fig. 1), in which users can choose to share their personal hearing health score. The personalized score, deduced from the range of SNRs from our normative data set (Int J Audiol. 2016;55:405 http://bit.ly/2gBmMuP; Potgieter et al., unpublished observations), also has a scoreboard feature that encourages users to track their score alongside their Facebook friends and VIPs who have taken the test. Participation via the #CanYouHearThat campaign is also encouraged. These initiatives allow us to reach a younger demographic; the peak number of persons tested are between 25 and 35 years old.
Accurate Detection of Hearing Loss
Test development was a partnership between the audiology and computer engineering divisions at the University of Pretoria led by myself and Dr. Herman Myburgh, in collaboration with Dr. Cas Smits from the VU Medical University Hospital in the Netherlands, where digits-in-noise testing originated.
The binaural hearZA digits-in-noise test is validated for accurate testing across smartphones with no significant difference between headphone or earphone type (Int J Audiol. 2016 http://bit.ly/2gBmMuP). Test criteria are set up to identify ear sensorineural hearing loss greater than 25 dB HL (PTA 0.5, 1, 2 & 4 kHz) and additional criteria for ear sensorineural hearing loss greater than 40 dB HL (PTA 0.5, 1, 2 & 4 kHz). Test accuracy across native and non-native English speakers approximates 90 percent with sensitivity of 95 percent (Potgieter et al., unpublished observations). These values ensure a valid screening test that can be downloaded to end-user smartphones and conducted with any headphone or insert earbud.
Hearing Health Monitoring
Smartphone health surveillance and monitoring has gained significant traction; an estimated 1.7 billion downloads are expected by 2017, and global revenues are projected to reach $21.5 billion in 2018 (Economist, 2016 http://econ.st/2g51oiG). In line with the global trend of health monitoring on smartphones, the hearZA app allows hearing health monitoring through a personal profile that tracks the user's hearing health score over time. An in-app notification prompts users to retake the hearing test annually to ensure there has not been any significant changes in their hearing health status. This monitoring feature can be personalized for different demographics with targeted preventive health messaging. For example, teenagers and young adolescents who are at significantly increased risk from music-induced hearing loss may be targeted with messages around safe listening behaviors (WHO, 2015 http://bit.ly/2g4WIJo). This approach also ensures greater general awareness of hearing health care, which traditionally has been a difficult and abstract health concept for the general public.
Decision Support Tool for Audiological Intervention
We partnered with the Ida Institute http://idainstitute.com/ to adapt a selection of their tools for in-app decision support in line with the principles of patient-centered care. Help-seeking and hearing aid uptake can be seen as a behavioral change in adults with hearing loss. A brief decision-support tool that incorporates user-driven design is offered as an optional two-minute guide to users who have failed the hearZA test (Fig. 2). The first tool to be incorporated is the Ida Institute's “Why Improve My Hearing?” questionnaire, which facilitates greater uptake of help-seeking by supporting the progression from more pre-contemplative and contemplative stages of change to action.
Referral Linkage to Audiologists
The hearZA app was launched in partnership with two professional organizations for audiologists in South Africa— the South African Association of Audiologists http://www.audiologysa.co.za/ and South African Speech-Language-Hearing Association http://www.saslha.co.za/. Members of these societies were offered the opportunity to register their practices on the hearZA cloud-based management platform. People who fail a hearing test can look up their closest audiologist based on their location within the app. People who have failed the test can take further action by requesting their closest audiologist to contact them directly. In this case, the hearZA cloud-based management portal notifies practices, and audiologists can log in to the secure portal to view the contact details. People are then not only able to detect a likely hearing problem but also receive care by connecting directly with their closest providers.
A smartphone platform for a simple digits-in-noise-based screening test lends itself to a wide range of far-reaching and impactful opportunities for increased awareness, detection, and uptake of hearing care.