Six of the seven specialist NHS gender services for adults “co-ordinated” their refusal to share data on health outcomes for patients who had been under the care of the now-closed Gender Identity Development Service (Gids), according to paediatrician Dr Hilary Cass. In her final report on Gids submitted to the government, Cass makes clear that the use by researchers of existing data held by the NHS “is usual practice” when looking to improve services. Seeking fresh data “would take a minimum of 10-15 years” the report pointed out, and there is already a paucity of good evidence on which clinicians can base their decisions on the care of patients presenting with gender dysphoria. “This research represents a unique opportunity to provide further evidence to assist young people, their parents/carers and the clinicians working with them to make informed decisions about the right pathway for them,” the report states. The clinics’ “disappointing” opposition to sharing their data “seemed to me to be ideologically driven,” Cass said. The decision by so many NHS gender clinics to reject the data requested by University of York researchers had “thwarted” efforts to secure the best possible evidence base. The report’s recommendations include the bald statement that NHS England and the Department of Health and Social Care “should direct” the clinics to participate.