I am trying to do a paired sample t test between values of SF-12 physical pre (A) and post (B). This is my syntax:
T-TEST PAIRS=A_SF12PhysicaHealth WITH B_SF12PhysicaHealth (PAIRED)
However, I always get this message:
"The correlation and t cannot be computed because there are no valid pairs"
And no output.
I am comparing 20 data entries with 20 other data entries.
How can I get rid of this issue? Did I miss something?
I imported my data from Excel.
Any help appreciated...