Harnessing mHealth to improve access to hearing care: Low material-cost, smartphone-based infant hearing screening at Seattle Children’s Hospital

Abstract

ObjectiveEarly childhood hearing loss is a neglected global health issue, with the largest and fastest growing burden in low- and middle-income countries. Universal screening is essential for early identification of children with disabling hearing loss, yet there is a lack of cost-effective, scalable technology suitable for resource-constrained settings. We aim to evaluate whether an innovative mHealth device can effectively screen for hearing loss in infants. MethodsWe recruited infants from ambulatory clinics at Seattle Children's Hospital between January and October 2022. All infants less than six months old with at least one patent ear canal were eligible. We used an open-source distortion product otoacoustic emission (OAE) probe using off-the-shelf earphones and microphones, with a material cost of $10, and a simple smartphone application to conduct single-step hearing screening. The results were compared to a commercially available OAE device that costs approximately $5000. Tests were conducted by research coordinators without prior clinical experience. Hearing status was confirmed via a two-step newborn hearing screening protocol and/or diagnostic brainstem auditory evoked response. Ear-specific primary outcomes included hearing loss prevalence, referral rate, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). ResultsEighty-seven infants (mean age 3.1 ± 1.8 months, median 4 months [1-5 months]; 39% female) were recruited, with a total of 143 ears screened. The sample prevalence of hearing loss was 10%. The referral rate for smartphone screening was 34%, while the referral rate for commercial device screening was 26%. Sensitivity and specificity for hearing loss with the smartphone device was 100% and 64%, respectively. The estimated PPV and NPV were 24% and 100%, respectively. Results were similar to the commercially available OAE device. ConclusionThe smartphone device effectively ruled out hearing loss. Although it over-identified hearing loss, the low PPV was comparable to published rates for OAEs in low-risk populations such as ours. Thus, smartphone-based OAE detection is a promising low-cost solution to the challenge of building scalable hearing screening programs in resource-constrained settings.