Hi--,
I am trying to properly subset and merge variables DONEPEZIL and MEMANTINE from dataset RECCMEDS to ADNIMERGE in order to assess whether each patient was using the medication or not at a given visit.
For some records variable CMCONT=No (i.e. Is the medication continuing? No) but DONEPEZIL=1. Does this mean that the patient was not using DONEPEZIL at this visit?
I spoke with members of the Clinical Core and all of the cases with CMCONT="No" have an end date for the drug (CMEND), suggesting that the drug was stopped at a specific date (so not continuing).