Association between two lab parameters over time

[AVoelp]

I have two lab values measured in a group of trial subjects at baseline and at four equidistant follow-up visits, and I want to analyze the association between the changes in these two parameters over time. What would be the best approach for this?

Thank you very much!

 

[fed2]

compute the change from baselines and take pearson correlation / scatterplot at each time point, probably the easiest.