You have to take into account that in Asian countries the reporting of sexual abuse is likely much lower because of social stigmatization. From what I've heard second-hand it's perceived as being shameful for your family to be a victim of such abuse, and I imagine that would affect the statistics.

I'm not agreeing or disagreeing with whether it causes actual child sexual abuse, it's just something to consider.

Be careful when comparing crime rates between countries. Japan, in particular, has...odd statistics.

http://articles.latimes.com/2007/nov/09/world/fg-autopsy9

Further, sex crimes are...different everywhere.

https://www.japantimes.co.jp/community/2014/12/08/voices/for...

There is some bias in that reporting. The US rate of autopsy 8.5 percent the Japan rate is 11.2%. So, if your comparing the US with Japan it's the US that's more likely to miss something based on national rates. As to the second, US rape victims are often told not to report and prison rapes are frequently just ignored.

From a sociology standpoint you need to be careful when doing cross country comparisons. But, reported statistics are not simply accepted at face value.

The US rate of 8.1% (https://www.cdc.gov/nchs/products/databriefs/db67.htm) is for all deaths. The Japanese rate of 11.7% (https://www.japantimes.co.jp/opinion/2016/02/27/editorials/t...) is for "unusual deaths". (Yeah, I wish I could find better figures, but all I get are abstracts for papers about the reasons for Japan's low rate of autopsies; the papers are behind paywalls.)