Does anyone know if there is a way to identify which parent cohort a participant is from, through the study id (pptid) in the SHHS dataset?
Unfortunately the parent cohort identifiers were purposefully stripped out of the SHHS dataset as part of BioLINCC's de-identification process. The only method I know of to get this level of information would be to go to BioLINCC and then request access to some of the parent cohorts themselves (e.g. ARIC, Framingham, CHS). BioLINCC holds on to a dataset that links the NSRR subject IDs back to their original cohorts.