[criddell]

It looks like the type of practice test matters a lot:

> a multiple-choice practice test increased intrusions of false alternatives on a final cued-recall test when no feedback was provided, whereas no such increase was observed when feedback was given

Sounds like practice tests are most useful when they are graded and the student gets that feedback. I suppose that makes sense. Flash cards and practice problems also fall under practice testing and it sounds like they were less effective.