Even-longer-term stability of spontaneous otoacoustic emissions.

This report is an addendum to a previous report by Burns [(2009). J. Acoust. Soc. Am. 125, 3166-3176] that measured spontaneous otoacoustic emissions (SOAEs) in 18 subjects, whose ages at the time of initial measurement ranged from 6 to 42 yr, for follow-up periods of up to 19.5 yr. The major finding of that report was that the frequencies of all SOAEs, in all subjects, declined over time, with an average decline of 0.25% per year. In this report seven SOAEs in the oldest subject were measured for an additional 13.7 yr, for a total follow-up of 33 yr, to age 75.