Sexual abuse among students could be “happening outside of school” rather than being caused by a culture problem within institutions, Ofsted’s chief inspector has said.

Amanda Spielman said testimonials posted anonymously by students on the Everyone’s Invited website have shown a “crossover very often between things happening outside of school bleeding into children’s lives within school”.

She added that Ofsted’s review into the issue will aim to make it easier for children to report sexual abuse allegations to their school.

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The watchdog will be visiting a sample of schools and carrying out a review into whether institutions have effective safeguarding measures in place, following the deluge of reports to Everyone’s Invited.

Ms Spielman told Sky News: “We can only inspect and discuss things with schools on inspection, things that schools and children themselves tell us about.

Everyone’s Invited sex abuse allegations: Students ‘have felt unable to speak to their school’

“I think Everyone’s Invited is showing quite how much is happening in that blurred space - with friends from school, and not friends from school but outside school - it’s the crossover very often between things happening outside of school bleeding into children’s lives within school.”

She added: “I have such a big concern about the fact so many of these young people have felt unable to tell their school what’s been happening to them.

“Many of these schools think that they have good routes - people that children can trust, who they can talk to - and yet somehow it’s not always adding up. That’s what’s clear. So [we will look at] how we make sure the pieces add up to something that gives young people the opportunity to report and talk about these things.”

Ofsted has said it will be speaking with headteachers and students at schools where allegations have been made, but Ms Spielman confirmed the “thematic review” does not aim to target specific cases or institutions.

She said: “The point is not to investigate individual cases or schools, it’s to put together this wider picture and say: ‘What are the aspects of the problem which are of greatest concern to young people? And what are the things that existing systems do well? And what more could potentially be done?’”

Ofsted’s review will also look at how well schools are teaching the new relationships, sex and health education curriculum, which covers sexual abuse, cyber-bullying, pornography and consent.

And the watchdog will look at whether current inspection programmes are robust enough on the issue of sexual abuse, and consider how schools can improve their coordination with other safeguarding organisations, such as social services.

The review is due to conclude by the end of May 2021.