Full Idea
The empirical 'content' of a theory is all its observable predictions. Two theories with the same predictions are empirically 'equivalent'. A theory which gets it all right at this level is empirically 'adequate'.
Gist of Idea
Predictions give the 'content' of theories, which can then be 'equivalent' or 'adequate'
Source
Tim Button (The Limits of Reason [2013], 05.1)
Book Reference
Button,Tim: 'The Limits of Realism' [OUP 2013], p.33