Pilot study of universal newborn hearing screening in Japan: district-based screening program in Okayama

Newborn hearing screening was started in Okayama Prefecture in 2001 as part of a nationwide pilot study in Japan. Nearly 50,000 infants have been screened to date, and an observational study and more than 2 years of follow-up of this population are described in this report.

Between June 2001 and March 2005 (45 months), 47,346 neonates were screened with automated auditory brain stem response systems and followed up for at least 2 years. This total corresponds to 95% of the infants born in the 44 gynecologic institutions in this district.

After undergoing the screening process twice, 248 infants (0.52%) received referrals; 108 of them had apparent bilaterally affected hearing, and 140 had apparent unilaterally affected hearing. Among the bilateral cases, hearing impairment was diagnosed in 40 infants, for a total prevalence of hearing impairment of 0.08%. In 3 additional infants who received a bilateral pass result and 1 infant who received a unilateral pass result, hearing impairment that was progressive or of late onset was subsequently diagnosed. The positive and negative predictive values were calculated as 40% and 99.993%, respectively.

The screening program was carefully designed to work in the Japanese society and to be well managed in Okayama Prefecture.