Hello, thanks for your response.
I am not very well versed in statistics so I will do my best to answer these questions. We are looking at the effect of a drug in the eye from baseline to day X. We need to CI for the treatment effect. I hope that makes sense.
So you must have a definiton of "treatment effect" in terms of a statistical parameter
(mean, median etc.). On the other hand, Wicoxon signed rank test does not test mean,
median etc., therefore it might be asked what the confidence interval for the z statistic is.