The ionization of atomic shells by the impact of spin-½charged particles in collisions involving largemomentum transfers is analysed within the framework of therelativistic plane-wave Born approximation. An expression isderived for the double differential cross section based on theimpulse approximation, which leads to a relationship between thegeneralized oscillator strength and the Compton profile. Theagreement between the impulse and plane-wave Born approximationsis then improved by introducing a Born Compton profile extractedfrom the numerically evaluated (Born) generalized oscillatorstrength. Calculations corresponding to the Bethe ridge ofdifferent atomic shells demonstrate the usefulness of thepresent approach for obtaining accurate generalized oscillatorstrengths at large momentum transfers with a minimum ofnumerical effort.