  We present a test with which to evaluate the calculated
isospin-symmetry-breaking corrections to superallowed 0+-to-0+ nuclear beta
decay. The test is based on the corrected experimental Ft values being required
to satisfy conservation of the vector current (CVC). When applied to six sets
of published calculations, the test demonstrates quantitatively that only one
set -- the one based on the shell model with Saxon-Woods radial wave functions
-- provides satisfactory agreement with CVC. This test can easily be applied to
any sets of calculated correction terms that are produced in future.
