Hey everyone,
I am looking for a check and a bit of advice.
A colleague of mine is working on a study where he wants to use ICC to check for consistency in performance. In this study, 20 participants took part in a single session. They all performed five max-effort kicks into a force plate during the session.
Which ICC should he use? He is interested in knowing how consistent the performances were, which means whether each repetition was similar to the others (within a given participant). Similar literature is a bit of a mess. People use different ICCs or preferably do not report what ICC they used.
I would suggest using ICC(3,1), but ICC(3,k) seems standard practice. They give vastly different ICC values, ~0.6 and ~0.9, respectively.
What would you suggest?