This would breach the guidance given in the headteachers' manual:
There are no standardisation keys, so it is not possible to extrapolate a child’s results in the tests proper from the Practice raw scores. Please do not draw direct inferences from the practice tests.
5. Be very wary about marking the Practice tests in school and extrapolating from these results.
There are no standardisations for the practice tests and it is not possible to accurately equate them with the tests proper. In addition, we asked GL Assessment to make test ‘A’ easier than the real tests and whilst Practice tests 1 and 2 are of a similar level, it should not be forgotten that they are public domain questions and some children may have encountered them before if older siblings sat the tests.