How do you read these statistics (Rape and sexual violence)?

[MrsFionaCharming]

I was reading a post on a blogging site, where someone was trying to make the point that actually, rape and sexual violence aren't feminist issues, because they actually affect more men than women.

To back this up, they referenced The National Intimate Partner and Sexual Violence Survey (Which actually makes some pretty interesting reading, if you're into social statistics and stuff).
( www.cdc.gov/ViolencePrevention/pdf/NISVS_Report2010-a.pdf )

They referenced table 2.1 and 2.2, pages 18-19 and said that it shows that more men are victims than women. Now, I interpret it differently. However, maths and data interpretation are not my strong points, and I'm worried I may have misunderstood it. Particularly as if the other person is right, then that undermines a lot of my feminist beliefs!

Can anyone help me out?

Just to add some context, this shows the original blog post, along with the picture that started the debate, and my response.

sparkly-octopus.tumblr.com/post/40147572849/misandryisalie-rhiannonsays-i-need

They only way (after looking at the tables) ir effects more men than women is because more male perpertrators are men.

Reading the figures women are raped more frequently although they do state the belief that under reporting is so great in male victims the figure is unreliable. Which is probably right as both sexes will under report sexual abuse (men can only be raped by men unless the women uses coercion). The current belief from my reading in the states most male rape take place in prison and will not be reported.

Comarision of the percentages for women (from table 2.1) and men (from table 2.2) concerning their lifetime exposure to various sexual violence gives:
(first figure is women, second figure is men)

Rape 18.3 1.4
Completed forced penetration 12.3 0.9
Attempted forced penetration 5.2 0.4
Completed alcohol/drug facilitated penetration 8.0 0.6

Other Sexual Violence 44.6 22.2
Made to penetrate * 4.8
Sexual coercion 13.0 6.0
Unwanted sexual contact 27.2 11.7
Non-contact unwanted sexual experiences 33.7 12.8

Yet it is claimed that men experience more sexual violence than women?

Sausageeggbacon wrote - "in the states most male rape take place in prison and will not be reported."

The male prison population in the USA is about 1 per cent of the total male population of the USA. Would this small percentage of the population have a significant impact on underreporting for figures of the USA as a whole, bearing in mind that the national rate for reported rape is 13 times higher for women ?

How much of the rape in female prisons is unreported?

Less than 10 percent of American men have served time in prison, so even if every man who was raped in prison reported the rape, the contribution to the national figure would be a maximum of 10 percentage points.

"if every man who was raped in prison reported the rape, the contribution to the national figure would be a maximum of 10 percentage points"

Does that rely on the assumption that each man is raped only once?

Well most of the figures for women only presume they have been raped once. For example a woman who was repeatedly raped by her husband over a 15 yr period would probably only get one count against her name (if she reported it of course and was believed and wasn't killed for doing that, because then the rape charge would be dropped in favour of murder).

I've been commenting on the "lifetime" statistics in the report of the OP. Therefore, my posts are about the numbers of American women or men who have been raped at least once. Those tables of statistics do not differentiate between single and multiple rapes of individuals.

Ah! Statistics, something I can actually say something intelligent about. I think that there is no evidence here backing up the position that men suffer worse than women. They suffer more or less equally in the "other sexual violence in the last twelve months" category, yes, but definitely less in the rape categories and the "lifetime" categories. It's possible that some of the difference is due to different reporting rates for men and women. However, there's no measure of that here, so any such claim is guess-work.

It's an interesting couple of tables, though. The difference between the "lifetime" and "last 12 month" figures is quite stark.

In the lifetime rape figures, women are ten-to-twenty times more likely than men to have suffered in any of the categories. In "other sexual violence", women still suffered more than men, but only by a factor of 2, or thereabouts.

In the "last twelve months" figures, there are no entries for rape for men because the reporting rate is too low. However, the figures for "other sexual violence" are very close - 5.6% overall for women, 5.3% for men, with similar differences across the sub-categories. Noting that a naive estimate of the 95% confidence interval on these figures is around +/-0.4%, the differences are small enough to be just sampling error.

That factor of two difference in the "lifetime" figures versus no significant difference in the "last-twelve-months" figures is interesting. I can think of several possible explanations:

1 - more men have suffered abuse recently than historically.
2 - fewer women have suffered abuse recently than historically.
3 - women are relatively less likely to report recent abuse than men.
4 - women are relatively more likely to report historic abuse than men.
5 - abusers of women change victims more frequently than abusers of men.

A series of these reports covering different time periods might give some insight - I haven't looked. Basically, I agree with vesuvia about the lifetime figures abd rape figures. But the last-twelve-months other-sexual-violence is a slightly more equivocal picture.

Tables 2.3 and 2.4 (ethnicity breakdowns by sex) are also interesting - white is not the best thing to be, somewhat to my surprise.

Thank you for all your input!

I guess his comment really was wrong then. Though I somehow doubt he'll be back to correct himself...