I would be grateful for some advice. I have an outcome which is the amount
of biofilm on a bone surface was assessed by a score of 1 to 4. In the
experiment a piece of bone is split into two, one part being treated with
the active ingredient and the other with a saline control. There are 12
samples in each of 4 test groups.
My uncertainty is in how to correctly handle the paired scores. Should I
calculate either their difference or ratio and use this as a composite
measurement in a subsequent Kruskal-Wallis or similar analysis, or is there
a more appropriate( correct) way of handling this data.
Many thanks,
Martyn
Dr. Martyn Sherriff
Reader in Dental Materials Science.
King's College London Dental Institute at Guy's, King's College and St
Thomas' Hospitals.
Department of Biomaterials and Biomimetics.
Floor 17, Rm 17/4, Guy's Tower, Guy's Campus.
London Bridge.
London SE1 9RT
England.
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