Dear Colleagues
I have been using "test-retest" method for calculating reliability by
applying the Pearson Product Moment (PPM) analysis. However, I have been
told that this not the right way to calculate reliability, and I should use
the ANOVA to calculate the reliability. Would you comment and a
The best measure of reliability is the standard error of measurement. It's
really the same as the within-subject standard deviation (SD you expect to
get when retesting a subject many times), but you take out any change in
the mean between trials. For any reasonable sample size and two trials