Status of the Newborn Hearing Screening in the 4-Months Age National Infant Health Checkup in Korea: A Nationwide Population-Based Study

BACKGROUND: The aims of this study are to review data on 4-months age National Health Screening Program for Infants and Children (NHSPIC) using a National Health Insurance Service (NHIS) database, and to analyze the newborn hearing screening (NHS) results and related characteristics of the 4-months NHSPIC for 7 years in South Korea. METHODS: We analyzed a NHIS database of infants who had participated in the 4-month age NHSPIC from 2010 to 2016. According to the results of hearing questionnaires and physical examination, we analyzed the outcomes of NHS and related infantile and socioeconomic factors. RESULTS: Among 3,128,924 of total eligible infants in Korea between the year 2010 and 2016, 69.2% (2,164,621 infants) conducted 4-months age NHSPIC, and 94.4% (2,042,577 infants) of which performed hearing questionnaires regarding NHS. Among the total hearing examinees, premature infants accounted for 3.6%, infants who were hospitalized in the neonatal intensive care unit (NICU) for more than 5 days accounted for 5.6%, and infants with head and neck abnormalities were 0.6%. The NHS performing rate was 79.1% for total hearing examinees in 2010, but gradually increased to 88.9% in 2016. The NHS performing rate in 2016 was 93.4% for premature infants, 91.7% for NICU hospitalized babies. The mean referral rate was 0.6% for total hearing examinees, 1.4% for premature infants, and 2.3% for NICU hospitalized babies. When we analyzed the NHS performing rate and the referral rate according to the household income level, the NHS performing rate of infants in Medical Aid programs was the lowest as 65.6%, and the NHS performing rates in other five levels of NHIS was higher ranging between 85.1% to 86.0%. The referral rate of infants in the Medical Aid program (3.8%) was significantly higher than those of infants in other classes (1.10–1.25%). CONCLUSION: The estimated overall NHS performing rate in Korea gradually increased and was 88.9% in 2016. The overall referral rate was low as 0.6%, and it was significantly different depending on the infant’s health condition and household income levels. We assume that our finding would help to establish policies managing hearing impaired children, and to develop the customized hearing care service programs considering the household economic levels.