Investigation; interpretation (8)
I believe the answer is:
analysis
I believe this clue is a double definition.
'investigation' is the first definition.
(analysis is a kind of investigation)
'interpretation' is the second definition.
(I've seen this before)
(Other definitions for analysis that I've seen before include "Determination" , "Detailed breakdown" , "Examination to determine component parts" , "Dissection and examination" , "Investigation of the component parts which make up the whole" .)