Guess it could be:
A) a computer based questionnaire to find out if we're secret axe murderers
or
B) an interview with a Psychologist to find out if we're secret axe murderers
Either way unless you're a secret axe murderer I don't think it's going to be something to sweat about
The interview should give them a pretty good idea of our personality I'd have thought, as always I'm just going to wait and see what is in the e-mail see if that reveals anything, and work towards the interview in the meantime!