Profs Pearce & Greenland have been working on a paper concerned with modelling strategies in epidmiology. This includes exploring issues of whether or not to adjust for covariables that are strongly correlated with the main exposure. They would like to include real life examples in this paper and have therefore asked colleagues if they could provide any. Debbie Lawlor provided an example of a published paper where the strong correlation between dietary sodium and potassium intake was an issue in exploring the relationship of infant sodium intake with subsequent offspring blood pressure. We would like to include reference to this in our modelling paper, including some additional analyses that were not in the original paper. DA Lawlor has agreed to complete these analyses for us, and she and ALSPAC will be acknowledged. We do not, therefore, require any data to be provided to us.