"Recruitment for the trial is due to start in 2025, months later than originally anticipated. Young people will likely be referred after a full assessment by specialist clinicians. A lot is still to be determined, including how many participants there will be.
Ultimately the scientists running the trials will need to establish whether people who get an intervention are better off than those who do not. In this case, do the puberty blocking drugs and their effect make the young people better off?
"Better off" in this instance includes the extent to which a young person's mental health may be improved if they are happy with their body. Quality of life is determined by various factors including self-confidence and self-esteem. As well as getting the personal views from the young people and parents, the trial could measure actual real life changes, such as time spent in education and time spent with family and friends.
But there are potential harms to study too, such as the possibility of reduced bone density. Some scientists suggest examining the impact on learning using a form of IQ test.Normal brain development is influenced by both puberty and chronological age, which usually act in tandem during adolescence. It's not clear how this is affected when puberty is suppressed. Brain scans are one way of understanding any effect.
Some scientists believe it may be possible to simply randomly assign trial participants into two groups where one gets puberty blockers, the other gets a placebo and nobody is aware which group they're in.But others believe a placebo group is impossible. They say the placebo group would go through puberty, realise they weren't on puberty blockers and potentially drop out of the trial or even find other ways to obtain puberty blockers. Either scenario would reduce the validity of the results.
Professor Gordon Guyatt and others have outlined a potential trial where the group of patients not receiving drugs would be made up entirely of children who are keen to socially transition, such as by changing how they dress and altering their name and pronouns. Researchers could then monitor the difference between the groups.
A second possibility is that both trial groups are given puberty blockers but one group gets them after a delay, during which time they receive psychological and emotional support. This would help researchers determine, among other things, whether their gender-related distress subsides during that delay while receiving the support.
Alongside this there would be a "matched" control group that doesn't take a placebo or puberty blockers, whether for health reasons or because they don't want to, that get similar tests and scans"