Fig. 1
From: Otoacoustic emission measurements: a test–retest reliability study
The vertical lines show the distortion level in dB SPL and the horizontal lines the f2 frequency in Hz. DPOAE indicates distortion product otoacoustic emission.The first session consists of the baseline measurement (measurement1 = M1). The second session (measure2 = M2) after 20 min. Third session (measure3 = M3) after 20 days. The figure shows mean DPOAE amplitude of the frequency variables from the test and retest conditions