I have N tissue samples, labelled as either A or B. 2 measurements are taken from each sample.
The data is not normally distributed.
I'm interested in 2 things: firstly, whether there is significant difference between the means of the 2 classes A and B (treating the repeated measures as independent data instances). This seems simple enough.
However I'm also interested to know how well the 2 measurements taken from each sample tend to agree. This sounds like intra-class coefficient to me, however each "class" in this case only contains the 2 repeated measures.
Would the stndard calculation of ICC suffice here? Should I repeat the test independently for the groups A and B or can I lump them together?
Thanks so much, I hope this isn't too basic. let me know if I can provide any other information.