Commenting on the Education Policy Institute report, sponsored by the NEU, Dr Mary Bousted, joint general secretary of the National Education Union, said:
"The National Education Union is pleased to sponsor this significant study which lays bare the facts of off-rolling. Sixty-nine thousand unexplained pupil exits from schools is a shocking figure and one which the Government needs to address. That pupils with complex needs are most likely to fall out of the school system shows that as a country we are failing our most vulnerable children.
"The reasons are complex, and providing guidance or policing schools will not solve the issue. Funding cuts to local authority support services and access to child mental health services are also making an impact on a school’s ability to support children most in need.
"It calls for further investigation that large multi-academy trusts, many of whom have been lauded by Government for vastly improved results, have higher than average unexplained exits.
"The performance culture in schools, where high GCSE grades and Progress 8 scores are what counts, needs to change. We need a clearer vision of a school system which includes all children and young people, an accountability system which doesn't treat pupils with complex needs as an afterthought, and adequate funding which enables schools to meet pupils needs."