The Otoacoustic Emissions in the Universal Neonatal Hearing Screening in China and India: An Update on the Asian States (2005 to 2025)

Background: China and India represent a large proportion of the Asian birth cohort and have produced extensive but heterogeneous evidence on neonatal hearing screening. This scoping review summarizes studies published between 2005 and 2025 on otoacoustic-emission-based neonatal hearing screening programs in these countries, with emphasis on program implementation, screening coverage, prevalence of congenital and bilateral hearing loss, follow-up, and intervention pathways. Methods: Searches were conducted in PubMed, Scopus, and Google Scholar using predefined keywords. Studies reporting screening protocols, coverage, prevalence, or follow-up outcomes were included. The standard English language filter was used. A total of 19 papers were considered for this review. Results: The data from the two assessed Asian states show two clearly different screening implementation profiles. In China, Universal hearing screening has evolved into a large-scale and increasingly standardized system, supported by technical specifications and regional or municipal databases; The reported screening coverage was 85.8% in early rural programs, 93.6% in Shanghai, and 97.9% in Liuzhou, while national institutional surveys indicate that UNHS has been substantially implemented in many regions. Reported Hearing Loss prevalence estimates generally ranged from 1.66 to 3.43 per 1,000 newborns, although follow-up and regional equity remain problematic, especially in rural settings. In India, the evidence is dominated by tertiary-hospital feasibility studies rather than a uniformly implemented national program. Reported Hearing loss prevalence estimates varied more widely, from 0.29 to 5.60 per 1,000 screened newborns, largely reflecting differences in study design, screening timing, referral completion, and population risk profile. Across both countries, OAE-based two-stage or sequential OAE+AABR protocols reduced referral rates and improved case identification, but loss to follow-up remained a recurrent limitation. Conclusions: China and India provide complementary models of neonatal hearing screening expansion: China demonstrates the effects of system-level scale-up, whereas India highlights the feasibility and constraints of hospital-based implementation in a highly diverse healthcare environment. Future priorities include stronger follow-up systems, harmonized reporting standards, and broader dissemination of outcome data through peer-reviewed publications.