You are testing two different methods of patient teaching in two unrelated groups and will be using a t test. Each group contains 21 patients. One group will attend classes and the other will complete an online program. Patients will be tested on their knowledge after the teaching.

Using the t table on p. 304, what is the critical value for this example, using a two-tailed test at an alpha of 0.05?

Using the same situation, if the calculated value for the t test is 3.8, what is your conclusion. Do you reject or fail to reject the null?

The degree of freedom is 40