Can repeated measures ANOVA be used in this case?

Question

I am trying to compare the change in score of inhaler technique in the same group of patients at different time points:

• before counseling
• 1 week after counseling
• 2nd week of counseling

I have scored the technique using an 8 item checklist. Each step performed correctly is scored 1 and each step performed incorrectly is scored 0.

What is a suitable test to use in this case? Would a repeated measures ANOVA work? If not, which test should I use?

Answer 1

The only problem I can see with using a repeated measures ANOVA would be the assumption that the error component of the score is normally distributed. If you think that is a reasonable assumption than use repeated measures ANOVA.

If the error component is not approximately normal there is a nonparametric repeated measures alternativeSee the following link:

In the case where the error is not approximately normal there is a nonparametric repeated measures test. See the following link:

Nonparametric Repeated Measures ANOVA