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I want to determine if method A provides the same results as method B. I obtain 2 sets of measurements using both method A and B. I therefore have 2 means that I want to compare using the paired t-test. I know that if the calculated T-value is higher than the chosen critical T-value, the null hypothesis can be rejected, therefore accepting the alternate hypothesis which is that the two means are significantly different. But what if the calculated T-value is lower than the chosen critical T-value? If we don't reject the null hypothesis, can we conclude that, statistically, method A and B are the same?