  A compact general integral formula is derived from which the fermionic
contribution to the one-loop coefficient in the perturbative expansion of the
MSbar coupling in powers of the bare lattice coupling can be extracted. It is
seen to reproduce the known results for unimproved naive, staggered and Wilson
fermions, and has advantageous features which facilitate the evaluation in the
case of improved lattice fermion formulations. This is illustrated in the case
of Wilson clover fermions, and an expression in terms of known lattice
integrals is obtained in this case which gives the coefficient to much greater
numerical accuracy than in the previous literature.
