Contextually appropriate school entry hearing screening protocol for low- and middle-income countries: A scoping review

Abstract

BackgroundIn low- and middle-income countries (LMICs), where universal newborn hearing screening programmes are often not available, school entry hearing screening programmes serve as a safeguard for early detection and intervention for hearing loss in school learners. ObjectiveTo determine a contextually appropriate school entry hearing screening protocol for LMICs. MethodsA scoping review was utilised to comprehensively search for relevant publications in the following electronic databases: Africa-Wide Information, CINAHL, Health Source: Nursing/Academic Edition, Cochrane Library, Pubmed, Scopus, and Web of Science. Studies included those that investigated school-based hearing screening protocols or programmes for LMICs among learners aged five to twelve years. The review was conducted and reported according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews checklist. ResultsThe search yielded 1863 studies, and after removing duplicates and ineligible studies, 19 studies were selected for data extraction. Pure tone audiometry screening was the most frequently used age-appropriate hearing screening test in the reviewed studies (n = 17). Conducting pure tone audiometry screening using 1, 2, and 4 kHz frequency combination resulted in referral rates ranging from 3.2% to 21%. In studies that included 0.5 kHz to the screening frequencies, referral rates ranged from 5.8% to 56%. Screening at 25 dB HL intensity level yielded referral rates ranging from 3.2% to 10.3%. Immediate rescreening reduced overall referral rates for learners referred for audiological diagnostic testing by up to 57%. Ambient noise levels were controlled by conducting screening in quiet rooms (n = 14) and utilising screening equipment that allows for monitoring and reducing environmental noise (n = 3). ConclusionAn ideal school entry hearing screening protocol in LMIC contexts could potentially utilise pure tone audiometry screening at 1, 2, and 4 kHz, using 25 dB HL screening intensity level with an immediate rescreen for learners with a refer result. School entry hearing screening should be conducted in a quiet room, preferably using hearing screening equipment capable of monitoring ambient noise levels to reduce false positive referrals.