Second, insulin resistance was obtained by means of an indirect
method, the HOMA model, and based on C-peptide. We had to
impute 63.6% of the C-peptide levels since they were under the
detection limit of 0.34. Sensitivity analyses with non-imputed Cpeptide levels showed about the same results with also no evidence
for an association when adjusted for all covariates (data not
shown).