Quality estimation of click-evoked oto-acoustic emissions

The Fsp statistic used by Elberling & Don (1984) as a quality estimator for averaged ABR recordings has been applied to averaged click-evoked oto-acoustic emissions. This statistic is akin to signal-to-noise ratio. The sampling distribution of Fsp under the null hypothesis that no signal is present has been determined by using no-stimulus trials. A determination by multiple replications in three normally-hearing adults demonstrated significant inter-subject variation, leading to a larger experiment in 58 children. From the latter experiment, the sampling distribution across subjects allowed the setting of a criterion value for Fsp of 2.0 which was only exceeded on 1% of trials. Thus, values above this criterion would indicate the presence of a signal in the average with a probability of Type I error below 1%. When two consecutive average both exceeded an Fsp of 1.6 the probability of Type I error was also below 1%.