Abstract
Four laboratories participated in this study to compare ascending and bracketing methods in manual determination of hearing thresholds using attenuators with 5 dB step. In all, 214 ears were measured. No significant difference was found between mean thresholds obtained with the two methods in the frequency range 0.5–6 kHz; the four-laboratory, six-frequency grand mean difference was -0.31 dB. The variability among subjects also remained essentially the same for the two methods. However, the bracketing method required a significantly longer test time than the ascending method.