  In a Randall-Sundrum type II inflationary scenario we compute perturbation
amplitudes and spectral indices up to next-to-lowest order in the slow-roll
parameters, starting from the well-known lowest-order result for a de Sitter
brane. Using two different prescriptions for the tensor amplitude, we show that
the braneworld consistency equations are not degenerate with respect to the
standard relations and we explore their observational consequences. It is then
shown that, while the degeneracy between high- and low-energy regimes can come
from suitable values of the cosmological observables, exact functional matching
between consistency expressions is plausibly discarded. This result is then
extended to the Gauss-Bonnet case.
