  The contribution of physical degrees of freedom to the one-loop amplitudes of
Euclidean supergravity is here evaluated in the case of flat Euclidean
backgrounds bounded by a three-sphere, recently considered in perturbative
quantum cosmology. The physical degrees of freedom (denoted by PDF) are picked
out by imposing the supersymmetry constraints and choosing a gauge condition.
Remarkably, for the massless gravitino field the PDF method and local boundary
conditions lead to a result for the trace anomaly which is equal to the PDF
value one obtains using spectral boundary conditions on a 3-sphere.
