An overhaul of special educational needs (SEN) provision will expose a shortfall in the number of specialist educational psychologists, which could disadvantage thousands of the most vulnerable young people, experts have warned.

Next Monday the new SEN code of practice will be introduced, hailed as the biggest reform in support and provision for 30 years. For the first time, there will be a single assessment and care plan covering education, health and social care from birth to the age of 25, including the legal right to educational support post 16.

But a shortage of educational psychologists to work in schools, colleges and nurseries could scupper the reforms, according to the union that represents the profession. The Association of Educational Psychologists (AEP) has claimed that there is already a shortfall in the number of trainee psychologists coming through the system.

And without extra investment, young people with behavioural difficulties and special needs could miss out on vital support, AEP general secretary Kate Fallon told TES. “We have to do more for young people at the same time as local authority budgets are being cut,” she said. “Educational psychologists are being pulled each and every way.”

Educational psychologists play a central part in helping providers to deal with the SEN requirements of their learners, by identifying the type of support required and assisting teachers in delivering it.

In order to help schools, colleges and other providers meet the increased responsibilities resulting from the change in the law, extra funding is being provided to increase the number of training places to 132 for each of the next two years.

But Ms Fallon said that this would barely provide half the number of educational psychologists required to meet the number of new vacancies being advertised, especially given that new recruits need a three-year training programme before they are ready to take up their first jobs. Under the new code of practice, the shortage was likely to worsen significantly, she added.

“We are reaching the point when educational psychologists will not be able to meet all the demands on their time,” Ms Fallon said.

“There is already a shortage of educational psychologists, but the workforce is being placed under increasing pressure to provide more and more school SEN and mental health support services in an environment where the number of new schools and new types of schools is rising, along with a growing number of pupils, leading to an increase in the number of young people with special needs and behavioural difficulties.

“There has never been a worse time for there to be uncertainty over how the training of future educational psychologists will be funded. The government needs to ensure that there is secure long-term funding for the training of educational psychologists with some urgency.”

Mary Bousted, general secretary of the ATL teaching union, said its members were also concerned about the lack of centralised planning under the new system, in which schools will be able to buy in their own provision. “It’s something our members are very worried about,” she added.

A Department for Education spokesperson said: “We recognise the vital role that educational psychologists play in supporting children and young people with special educational needs. That is why we are providing pound;5 million per year to support 132 new training positions - up from 120 - and why we have retained their statutory role in the new SEN and disability system.

“We are providing significant additional funding to councils to support the reforms as they are brought into effect on 1 September, including a pound;70 million SEN reform grant and a pound;45.2 million SEN and disability implementation grant.”