Charities should follow the Cass Review findings and ensure they keep up to date with any future changes to guidance or legislation, the sector’s watchdog has said.

The Charity Commission made a statement on wider issues as it published its report into the Mermaids charity, which supports gender-questioning young people.

The watchdog said charity trustees working in this area “need to ensure that they have regard to the findings, conclusions and recommendations of the Cass Review”.

The independent review of gender identity services for children and young people, published in April, concluded children’s gender care is an area of “remarkably weak evidence” and young people have been caught up in a “stormy social discourse”.

Its author, Dr Hilary Cass, now Baroness Cass, advised a more “holistic and personal” approach to care, and said there had been a “lack of high-quality research” assessing the use of puberty blockers in adolescents who were experiencing gender dysphoria.

She also advised a “more cautious approach” to social transitioning of young children, saying changing pronouns, names and clothes from a young age could lead to a greater sense of urgency for medical interventions such as puberty blockers.

On social transitioning, she said “parents should be actively involved in decision-making unless there are strong grounds to believe that this may put the child or young person at risk”.

The charities watchdog, in the findings of its report into Mermaids, said it had ordered the organisation to review statements on its website about puberty blockers being “an internationally recognised safe, reversible healthcare option” – something it has since done.

The commission also said the charity should ensure parents are informed if it provides chest binders to children in future, in line with the Cass Review’s recommendations around social transitioning.

In its wider conclusions for the charity sector, the commission said: “Trustees who work in this area need to ensure that they have regard to the findings, conclusions and recommendations of the Cass Review and ensure that they have reviewed their charity’s literature, website and guidance in light of them.

“Furthermore, trustees should have the mechanisms in place to ensure that they keep up to date with any future changes to guidance or legislation.”

Commission chairman Orlando Fraser said: “As the report indicates, there are lessons for other charities working in these areas, including that they need to have regard to the findings, conclusions and recommendations of the Cass Review.”

Following the review, The Children’s Society said it should be a “watershed” moment, and NHS England said the health service is “very grateful” for its author’s work.

The LGB Alliance said it was “pleased and relieved” at the commission’s guidance, adding: “It is horrifying to consider how many children, distressed by their emerging same-sex sexual orientation, were persuaded by Mermaids that their bodies were ‘wrong’ and must be fixed by drugs, or even by surgery.”

However, not everyone welcomed its recommendations, with the British Medical Association (BMA) pledging to “critique” the review and make recommendations to improve a healthcare system which it said has “failed transgender patients”.

The doctors’ union had called for the implementation of the recommendations to be paused during its evaluation – a suggestion rejected by NHS which said it has “full confidence” in the review’s final report.