Congenital and early-onset hearing loss is a common sensory disorder with substantial long-term consequences for speech, language, educational attainment and social development when detection and intervention are delayed. Early identification through newborn hearing screening enables diagnostic confirmation, early hearing amplification or cochlear implantation and entry into early intervention programs — actions that materially improve language and developmental outcomes. Population-level estimates of congenital hearing impairment vary by setting and by the screening protocol used. In many high-income settings the commonly cited prevalence of bilateral permanent congenital hearing impairment in the general newborn population lies between about 1 and 4 per 1,000 live births; Indian studies and program reports have reported a wider range. Several single-center and programmatic newborn screening reports from India estimate prevalence values between approximately 0.6 to 8.8 per 1,000 screened newborns depending on protocol (single OAE, two-stage OAE→ABR, automated ABR, or targeted high-risk screening), population (well-baby vs NICU), and completeness of follow-up. India has substantial regional diversity in health-care infrastructure, neonatal risk profiles (e.g., rates of NICU admissions, perinatal asphyxia, neonatal sepsis), and adoption of screening protocols (single-step OAE, two-step OAE→ABR, AABR). Reported prevalence estimates therefore vary widely between programs and studies; programmatic reports and HTA documents have quoted pooled or “typical” figures (e.g., 5–6 per 1,000) but these derive from heterogeneous data and are not necessarily restricted to studies using formal newborn hearing screening protocols with confirmatory diagnostic testing. A transparent systematic review and meta-analysis restricted to studies of newborn hearing screening (OAE and/or ABR) performed at birth or in the neonatal period will (1) provide a pooled estimate useful for national planning, (2) quantify between-study heterogeneity and drivers of variability (screening protocol, NICU vs well-baby, single vs two-stage screening), and (3) highlight gaps in follow-up, reporting, and study quality that affect prevalence estimates in India.
Prasad et al. (Thu,) studied this question.