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

Objectives: 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. Methods: 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. Results: 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. Conclusions: The screening program was carefully designed to work in the Japanese society and to be well managed in Okayama Prefecture.