“The authors were skeptical about the validity of the responses regarding circumcision status. To address this question they asked a group of men whether or not they had been circumcised. The men were then examined by a physician.
Of the 56 men who stated they were circumcised, 19, or 33.9%, were found to be uncircumcised. Of the 136 men who stated they were not circumcised, 47, or 34.6%, were found to be circumcised.
These data demonstrate that the findings from studies using interview data may not always be clear-cut.”
I picture the author of our epi textbook typing up that last line and then annoying his family the rest of the day by periodically breaking into a gleeful snickering fit.
… “Clear-cut.” Heh.