  We study the observational viability of coupled quintessence models with
their expansion and growth histories matched to modified gravity cosmologies.
We find that for a Dvali-Gabadadze-Porrati model which has been fitted to
observations, the matched interacting dark energy models are observationally
disfavoured. We also study the distinguishability of interacting dark energy
models matched to scalar-tensor theory cosmologies and show that it is not
always possible to find a physical interacting dark energy model which shares
their expansion and growth histories.
