Study found there was no reliable difference between paper and computer prototype usability results. This has been studied quite a lot and seems to play out each time.
The analyzed 1270 participants. The participants made reliably more comments about the computer prototypes, but both types of testing found equally severe issues.
More fodder for me to eschew the computer prototype that I see other spend so much time and money making work well. They might as well just build an app. Go paper. Test sooner, test more often.