I have a question on comparing means and I would be really thankful if you could help... I have a data set that contains responses from a questionnaire (so one group only, N=216). The questionnaire forms 3 scales (A,B,C).
My means for these scales are: A:mean=14.92, with SD=6.96 B:mean=10.51, with SD=7.32 C:mean=14.04, with SD=11.12
I would like to compare these three means to see which scale is higher (where people scored higher). What should I do? Should I first transform my data into z-scores before making comparison? Thank you for your time and help.