Peer Pressure?

I heard a piece of rather amusing report this morning and thought of sharing with you.

There was a report that the proportion of girls who were from girls' school was 50% among all the girls who have to receive help for eating disorders. My first reaction was it seemed very high and could it be due to peer pressure. On second thoughts, a girl will either come from a girls' school or a co-ed school, so the proportion of 50-50 is just a simple probability?

Then you may have argued that the proportion of girls' school to co-ed schools is definitely not 50-50, so the number of girls who suffered from eating disorders and who studied in girls' schools is still high. Then I will counter-argue that the number of girls in a girls' school is definitely higher than the number of girls in a co-ed school, thus the 50-50 again is a simple probability?

Am I getting more and more cynical about such reports and studies or am I over-defensive over girls from girls' school?