How does one measure biblical literacy? First, which canon to use as the measure? Do you test specific scripture awareness like John 3:16? If so, which translation? I just don’t see how such a test is even approachable without significant bias.
I would guess the Barna study goes into detail about it. From the story while 87% of latinos say they own a bible, only 8% of those actually admit to spending any time reading it.
Can’t be truly literate about something if you never read it. You can however very easily quote a sentence or two out of context when it seems to help advance your point.