When you get an error or questionable message in the log, please copy the data step or procedure along with any messages from the LOG and post them in the code box.
Then you can reference your explicit question. The code you provided does not generate an error for me but does have a NOTE (which very specifically is not an error) that you might not expect.
You might want to add an explicit Input to advance to the next line when expected:
data easyway;
do Group = 'Placebo','Active';
do Subj = 1 to 5;
input Score @;
output;
end;
input;
end;
datalines;
250 222 230 210 199
166 183 123 129 234
;
That will get rid of the note:
NOTE: SAS went to a new line when INPUT statement reached past the end of a line.
It is usually a good idea to use an explicit input to stop the @; reading when you know you have read the expected data.
If you have more complex input file then this can be critical to control where and when values get read.