Advance screening of power survey (7)
I believe the answer is:
preview
'advance screening' is the definition.
'preview' can be an answer for 'screening' (preview is a kind of screening). I'm not certain of the 'advance' bit.
'power survey' is the wordplay.
'power' becomes 'p'.
'survey' becomes 'review' ('review' can be a synonym of 'survey').
'p'+'review'='PREVIEW'
'of' acts as a link.
Can you help me to learn more?
(Other definitions for preview that I've seen before include "Early sight of something coming" , "Early chance to see" , "Film trailer" , "special showing" , "A showing before opening night" .)