For the patients the age in years (Y) is shown as well as whether they carry the WFS1 mutation and their age of onset of audiological complaints (AoO). The results of the audiological examination tests are depicted for each ear separately. The ears of the mutation carrying individuals have an increased Fletcher Index (FI; mean threshold for 0.5, 1, and 2 kHz) and a decreased maximum speech recognition score (MSRS). Abbreviations: female (F); male (M); right ear (RE); left ear (LE); decibel hearing loss (dB HL); electronystagmography (ENG); auditory steady-state response (ASSR); computed tomography (CT); not available (Na).