NO!!!
You keep ALL datasets in the long layout, append that, and do any transposing (either with TRANSPOSE or REPORT) as a FINAL(!!!) step.
I will say this a last time, in the hope that it finally sinks in:
ONE DOES NOT WORK WITH WIDE DATASETS!!!
Wide datasets are needed for regression (where you need a lot of predictors side-by-side with the outcome) or for presentation purposes. They are useless for work like joining, subsetting, grouping or appending (what you experience right now).
So you keep all your data in a long layout, can then simply append (as the structure is constant) and let SAS procedures do the work of transposing for you when needed for reporting.
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Learn how use the CAT functions in SAS to join values from multiple variables into a single value.
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