If you choose a difference hypothesis, Minitab displays the difference between the means and the confidence interval for that difference. If you choose a ratio hypothesis, Minitab displays the ratio of the means and the confidence interval for that ratio. If the confidence interval is completely within the equivalence interval, then you can claim that the two groups are equivalent.

For the contact lens data, the difference between the contact angles is small, -0.11929. The confidence interval for the difference (-0.31960, 0.081034) falls completely within the equivalence interval (-0.5, 0.5). Thus you can conclude that the new solution cleans as well as the leading brand.

The equivalence plot is a useful way to visualize these results.