Inspectors have found "significant weaknesses" with special needs provision in more than half of local authority areas visited over the past five years, new statistics show.
And of the areas with shortcomings that have since been revisited, less than half were making "sufficient progress" in addressing all major issues.
The data, published today, shows that Ofsted and the Care Quality Commission (CQC) carried out joint inspections of special educational needs and disabilities (SEND) arrangements in 116 of the 151 local areas across England between May 2016 and March 2021.
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Over half of the areas visited (51 per cent) were required to produce and submit a written statement of action to the Ofsted chief inspector – the worst possible inspection outcome.
The watchdog said this was "an indication of significant weaknesses" in their SEND provision.
Ofsted and the CQC have since revisited 21 of these areas. Inspectors found that only nine were making "sufficient progress in addressing all significant weaknesses".
Tes previously revealed that more than half of the first 100 inspections of SEND services had found significant weaknesses.
Damning inspection reports highlighted recurring problems, including poor quality of education, healthcare plans, concerns about the high numbers of children with special educational needs being excluded or absent from school, poor exam outcomes for SEND children, and a lack of confidence among parents in the system.
SEND area inspections were put on hold in July last year because the disruption to education, health and care services during the coronavirus pandemic made it "impossible" to reach valid judgements.
However, Ofsted said that, in the interim period, it would conduct visits with the CQC to understand what children and young people with SEND had experienced during the lockdown.
In March, the watchdog announced that full SEND area inspections would resume from June.