“…Several studies found that most CAS effects were evident at 1-2 kHz [ 4 , 23 , 24 ]. However, other studies did not support this contention; DPOAE CS varied in different ways depending on the primary frequency [ 16 , 25 , 26 ]. In our study, the extremes of frequency bands centered at f2=1,189 Hz and 5,657 Hz afforded significantly greater DPOAE CS than did the mid-range stimulus frequencies (2 kHz to 4 kHz) ( Fig.…”