This article has a couple of interesting features.
1) Normally when you look at the effectiveness of a treatment you compare people who were treated with people having the same condition who aren't. This study compared people who were treated with the general population. Thus it's not clear how useful the results are.
2) They also looked at the results of treatment during two different time periods. The results are instructive. The increase in crime rate was only significant those treated before 1989. Also, "In support of this notion, the survival curve (
Figure 1) suggests increased mortality from ten years after sex reassignment and onwards. In accordance, the overall mortality rate was only significantly increased for the group operated before 1989. However, the latter might also be explained by improved health care for transsexual persons during 1990s, along with altered societal attitudes towards persons with different gender expressions.
[35]"
There are other studies that suggest that the mental health of transsexuals is strongly influenced by the attitudes of those around them, particularly family. It is not surprising that the increased acceptance would have a beneficial effect. Conservatives, of course, want to get rid of that progress.
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