parity in numbers Gender Variance different kinds of surgery Prevalence, incidence, growth and geographic distribution report different kinds of surgery small in number different kinds of surgery report report different kinds of surgery GIRES’ report different kinds of surgery parity in numbers Gender Variance report Best estimates Prevalence, incidence, growth and geographic distribution different kinds of surgery report report report Best estimates A 2009 study different kinds of surgery report report report different kinds of surgery Best estimates different kinds of surgery a 2009 report parity in numbers