Don't see why they'd need it. It's not like they're doing space walks during this time, and the real goal here is to gauge survival / mental change. You're also possibly better off testing someone who hasn't had prior training, so you can better measure how new training will effect them during the trial. It would probably also make developing a measurement for finding which people shouldn't go on a trip like this before they actually do so a bit easier, as it'd be similarly less tainted.