SAS day 47: Nadir value
Definition: Nadir value is the lowest value of best response prior to current assessment or the shortest SLD (sum lesion diameter) along with the tumor measurement progress.
Example:
Measurements: 28,29,27,30,35. Nadir:28,28,27,27,27
Measurements:28,28,27,27,27. Nadir:28,28,27,27,27
Note: Nadir value is changing with the time NOT a global minimum.
Challenge: How to find nadir Value?
Key Step/Functions: Retain, Min
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image
almapapi / Pixabay[/caption]
data tlnadir;
/*merge tlsum tl_sum_ly;*/
set tsum;
retain nadir;
by subject aday;
if first.subjid then nadir=.;
nadir=min(sld,nadir);
nolymph=sld-lymph;
run;
Output:
image
Sample Data:
data a;
input subjid $ sld aday;
datalines;
001 28 1
001 29 2
001 27 3
001 30 4
001 35 5
002 28 1
002 28 2
002 27 3
002 27 4
;
run;
