I would expect that even as a fairly squishy pro-abortion Westerner (incredibly discomforted with the procedure but even more discomforted by the actions necessary to ban it), I'm likely to underestimate the health risks of even contragestives, and significantly underestimate the health risks of abortion procedures. Discussion in these circles also overstates the effectiveness of conventional contraception and often underestimates the number of abortions performed yearly. The last number is probably the easiest to support through evidence, although I'd weakly expect it to 'fool' smaller numbers of people than qualitative assessments.
I'm also pretty sure that most pro-choice individuals drastically overestimate its support by women in general -- this may not be what you're looking for, but the intervals (40% real versus 20% expected for women who identify as "pro-life") are large enough that they should show up pretty clearly.
It wouldn't surprise me if people generally overestimate the safety and effectiveness of drugs and medical procedures-- would you want to compare the accuracy of people's evaluation of contraceptives and abortions to their evaluation of medicine in general?
It also wouldn't surprise me if there's a minority who drasitically underestimate the safety and effectiveness of medicine.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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