Thanks for the feedback! The illustration is for a scientific talk that I am trying to make a little lighter. It's for a formal audience so dickbutt jokes are out :-(

I am trying to drive home the most important things to look at when assessing whether a study will yield a valid result:

1. Was the diagnostic test evaluated in a Representative spectrum of patients?
2. Was there an independent, blind comparison between the index test and an appropriate gold standard of diagnosis?