Coincidentally running the numbers on race and ethnicity from the fourth AB/DL survey: For one reason or another, the AB/DL community (or at least the ones who finished the survey) were mostly white.
Actually, with a large enough sample, one sees a shift of roughly five years: On average, the diaper type preferred in fantasy is the same as the type an ABDL roughly five years younger would have been raised in.
I've long had a curiousity: If the reason we're AB/DLs is a universal human trait, we'd expect to see particular varieties of AB/DLs growing up in certain regions.