The Status of Newborn Hearing Screening in Japan: Past, Present, and the Future

Abstract

This review article summarizes the chronological history of newborn hearing screening (NHS) implementation in Japan. Beginning with experimental pilot programs implemented in the early 2000s, efforts have been made to establish NHS throughout the country. The results of and responses to these pilot programs are introduced, analyzed, and discussed. Data reported annually, from 2014, by the Japanese Ministry of Health, Labour, and Welfare (MHLW), introduce the overall progress achieved in NHS throughout the country. The most recently published MHLW report, from 2019, cites a screening rate of 90.8%. Analysis of the data from these reports, however, suggests that while clear progress has been achieved, "known-screening" rates are lower than the "surveyed" rates cited. Published NHS program data from three pilot programs as well as publicly available data from one prefecture and unpublished data from an additional prefecture are analyzed and compared to the national figures. Hearing impairment occurrence frequency for newborns in Japan, calculated from two large data sets, reveals an average occurrence rate of 0.14% or one per every 1,400 births. Progress is observed in terms of an expanding coverage rate for NHS in Japan. Work remains, however, to achieve a screening rate of 95% or higher. Additionally, a protocol for ensuring quality standards for NHS is recommended. Data collected and analyzed for this review may inform planned efforts to introduce more efficient digitized NHS program management systems in Japan as well as in other countries where NHS program improvement efforts continue. Such systems may serve to enable effective monitoring of pre-determined screening program protocols and thus may make a shift from a 1-3-6 to 1-2-3 protocol more feasible.

Keywords: early intervention; follow-up testing; hearing impairment; newborn hearing screening; screening; tracking.

Figure 1. Newborn hearing screening rates per year from 2006 to 2020 including annual birth data and hearing impairment counts per year by category.

Achieved screening rates are displayed as vertical bars with percentages displayed at the top of each bar for 2006 to 2020. The percentage scale for these figures is displayed on the left vertical axis. The total number of hearing impairment cases is plotted as an orange line from 2006 to 2020 with the scale displayed on the right vertical axis. The number of bilateral severe to profound hearing impairment cases is plotted as a green line from 2006 to 2020 using the same scale on the right vertical axis. The exact number of cases for total hearing loss and bilateral severe to profound hearing loss is displayed within the vertical screening rate bar with the total number on the top and the number of bilateral severe to profound cases on the bottom. The total number of births per year is displayed at the top of the figure.

Figure 2. Actual births as reported annually by the Ministry of Health, Labour, and Welfare plotted together with births reported on the newborn hearing survey. The reported screening rate is from the newborn hearing survey. The known rate is calculated using annual total births instead of the total reported in the surveys.

Actual births, displayed as blue vertical bars, are from the Ministry of Health, Labour, and Welfare e-Stat statistics website. Reported births, displayed as orange vertical bars, are the total numbers reported in the annual newborn hearing screening survey. The number of newborns screened, as reported from the annual survey, is displayed as a vertical grey bar. The scale for these vertical bars is displayed on the left vertical axis. Reported screening rates, from the annual survey, and the known rate calculated by dividing the total number of screenings by the number of annual births, are displayed as yellow and blue lines respectively. The percentage scale for these numbers is displayed on the right vertical axis.