I need your expertise.
How do you adjust for significantly different baseline outcome measures in a longitudinal analysis? Is there a need to adjust for it? If so, is it appropriate to use the constrained longitudinal data analysis (cLDA)? cLDA is used where the main effect of
Treatment is removed, i.e. treatment levels are constrained to have the same baseline mean of the response variable.
My formula in the mixed model:
y ~ Time + Time*Treatment + (1|ID)
Appreciate your help. Thanks!