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 cat food data, the difference between the protein content of the discount food and the original formulations is -0.12122. The confidence interval (-0.48345, 0.24101) falls completely within the equivalence interval (-0.5, 0.5). Thus you can conclude that the amount of protein in the discount cat food is equivalent to the amount of protein in the original formulation.

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