Well, i can't. i have no idea what "SDTM" stands for.
STUDY DATA TABULATION MODEL
Its standardization of data as per FDA guidelines.
Dataset level, variable level and value level.
EX or EC ?
This is more of a study design question. This should be specified in the Clinical Trial Protocol or Statistical Analysis Plan.
Typically intervention datasets collect /capture information about procedures and treatments given as per protocols. This includes Substance Use (SU) . This a possible location.
However it all depends on Study design / protocol.
Learn how use the CAT functions in SAS to join values from multiple variables into a single value.
Find more tutorials on the SAS Users YouTube channel.
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