Changed doctor provided, that is, daughters come round (8)
I believe the answer is:
modified
'changed' is the definition.
(modifying is a kind of changing)
'doctor provided that is daughters come round' is the wordplay.
'doctor' becomes 'mo' (medical officer**).
'provided' becomes 'if'.
'that is' becomes 'ie' ('i.e.' can be a synonym of 'that is').
'daughters' becomes 'dd' (I've seen this in other clues).
'come round' means one lot of letters goes inside another.
'if'+'ie'='ifie'
'ifie' going inside 'dd' is 'dified'.
'mo'+'dified'='MODIFIED'
(Other definitions for modified that I've seen before include "Reformed" , "tweaked" , "Changed or qualified" , "Changed slightly, form or quality" , "Altered, changed" .)