Figure 3. Equivalence testing confirms equality (or near equality) between groups for all parameters tested between WT and dCKO mice.

Equivalence testing allowed for the identification of similar groups and was based on the estimated means and the confidence interval (CI) for the difference in means. An absolute difference of Δ was determined such that a difference less than Δ essentially coincided with equality of means. Any pair of means with a CI that was completely contained in −Δ to +Δ was considered equivalent. The Δ values for organ of Corti length, ABR, and regularity, were determined to be 0.5mm, 10dB, and 10%, respectively. P0 WT and P0 dCKO, P21 WT and P21 dCKO, and four month WT and four month dCKO organ of Corti lengths were equivalent (A). At P21, click and 16 kHz ABR responses were equivalent between WT and dCKO (Bi). At four months of age, click ABR responses were nearly equivalent while 16 kHz ABR responses were equivalent (Bii). After cisplatin treatment, neither click nor 16 kHz ABR responses were equivalent at the 10dB threshold; however, were equivalent at the 15dB threshold (Biii). All regularity measurements: P21 WT vs. P21 dCKO (Ci), four month WT vs. four month dCKO (Cii), P21 WT vs. four month WT (Ciii), and P21 dCKO vs. four month dCKO (Civ), were equivalent.