Young people with special educational needs are three times more likely to be out of school, work, or training than their peers, official figures suggest.
More than a third (39 per cent) of 19-year-olds with a statement of SEN are "NEET" - not in education, employment or training - according to figures published by the Department for Education.
In comparison, 12 per cent of 19-year-olds with no special educational needs are considered NEET.
The figures are contained in a new DfE report on SEN.
The study says that more than a fifth of pupils in England (21 per cent), around 1.67 million in total, have special educational needs.
This has risen from 1.52 million (19 per cent) in 2006.
The numbers of pupils with formal SEN statements has fallen from 236,730 in 2006 to 224,210 in 2011.
Of those with statements this year, the most common types of SEN were autistic spectrum disorder and moderate learning difficulties.
Boys are nearly two and a half times more likely than girls to have SEN statements at primary school and nearly three times more likely to have SEN statements at secondary school.