Checks out some Cat Stevens' backtrack (4)
I believe the answer is:
vets
'checks out' is the definition.
(I've seen this in another clue)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for vets that I've seen before include "Checks out" , "Screens the animal doctors" , "Examines the animal doctors carefully?" , "Siegfried and Tristan Farnon, for example" , "Thoroughly examines" .)