A group sequential test for ABR detection

<b>Objective:</b> To detect the auditory brainstem response (ABR) automatically using an innovative sequentially applied Hotelling’s <i>T</i> ² test, with the overall goal of optimising test time whilst controlling the false-positive rate (FPR). <b>Design:</b> The stage-wise critical decision boundaries for accepting or rejecting the null hypothesis were found using a new approach called the Convolutional Group Sequential Test (CGST). Specificity, sensitivity, and test time were evaluated using simulations and subject recorded data. <b>Study sample:</b> Data consists of click-evoked ABR threshold series from 12 normal hearing adults, and recordings of EEG background activity from 17 normal hearing adults. <b>Results:</b> Reductions in <i>mean</i> test time of up to 40–45% were observed for the sequential test, relative to a conventional “single shot” test where the statistical test is applied to the data just once. To obtain these results, it will occasionally be necessary to run the test to a higher number of stimuli, i.e. the maximum test time needs to be increased. <b>Conclusions:</b> The CGST can be used to control the specificity of a sequentially applied ABR detection method. Doing so can reduce test time, relative to the “single shot” test, when considered across a cohort of test subjects.