Dear Dr Wicklin I am developing a short course and would like to use your example of mixed effects modelling using splines for estimating the effect of a treatment on blood lead contents among toddlers, the data is reported by Fitmaurice and Ravichandran (2008). Your codes are in SAS. I am running the course using Stata. I wonder whether you have Stata codes for this. I will be grateful for your help. regards Haider Mannan, PhD