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