"Missing little fingers"? I've never been to Japan, but as far as I know, most folks aren't in the Yakuza. Also, I wouldn't be super worried about blinding in

"Missing little fingers"? I've never been to Japan, but as far as I know, most folks aren't in the Yakuza. Also, I wouldn't be super worried about blinding in this case - a length measurement is not particularly subjective. I cannot see how unconscious bias would reasonably add 20-50% (postulated effect size) to intestine length. I'd personally consider the results valid even without blinding, provided a rigid procedure was chosen for measuring intestine length.