Cecilia Anim describes how she was told to take her disabled daughter for a test to see if she could get a job guardian.co.uk

Ruth Anim needs constant one-to-one care, has no concept of danger and attends life skills classes to learn practical things like how to make a sandwich or a cup of tea. So it came as a considerable surprise to her mother, Cecilia, that an official assessment of her daughter's abilities classified her as someone who would be capable of finding work in the near future.

The report contained a number of factual errors, perhaps most remarkably the assessor's description of the 27-year-old as a "male client", but more disturbing for Anim was the conclusion of the doctor who carried out the test: "I advise that a return to work could be considered within 12 months."

Anim says: "For Ruth to go to work is actually totally unimaginable. She can't even cross the road without someone going with her; she doesn't know that if a car hits you it will kill you; she has no concept of danger." Her daughter was born with complex medical needs, learning disabilities, a heart problem and epilepsy. "She is somebody who has a one-to-one carer – is she meant to go to work with her carer?"

As a result of the assessment, Ruth was assigned to a category known as the work related activity group, and required to attend the jobcentre regularly to begin mandatory preparations for going to work.

Cecilia Anim's amazement at the written report, describing her daughter's work capability assessment (WCA), the test to determine fitness for work, echoes the shock felt by hundreds of thousands of former claimants of incapacity benefit over the last three years, after undergoing the stringent new computerised test to check their continued eligibility for benefit payments.

Since the test was introduced in 2008 more than 600,000 people have appealed against the assessments; the cost to the state of those appeals has risen from £25m in 2009-10 to £60m in 2011-12. About 38% of those who appeal against an initial fit-for-work finding see that decision overturned on appeal and benefits granted. Welfare rights organisations and charities have voiced consistent unease about the test and the way doctors employed by the private IT firm Atos, which is paid £100m a year by the government to carry out the test, have implemented it.

Last week Labour called for a "fast and radical" overhaul of the system, admitting the policy it introduced when in government was not working.

As deputy president of the Royal College of Nursing, Anim can project her fury about the experience her daughter endured far more powerfully than most individuals going through the system. This awareness has heightened her desire to talk about the "injustice of the process", to educate people about how inaccurate the assessments can be.

"I am able to fight back, but what about the people who are not able to fight back? It's causing a lot of problems for a lot of people," she says. "My daughter's consultant neurologist was beside himself with fury when I told him. The first question he asked was, 'Have they done a risk assessment?' "

Ruth's case is by no means exceptional. Mencap, the charity which supports people with a learning disability, says it has seen countless similarly surprising cases of misclassification of vulnerable clients, many of whom are told they are not eligible for any sickness or disability benefit and must seek work immediately.

The principle underlying the WCA is that a health condition or disability should not automatically be regarded as a barrier to work, and in theory the policy is designed to ensure that support is available to help people find work. Anim says there is nothing she would like more than for her daughter to find a job, just as she would like her to get married and have the kind of life her contemporaries have, but she argues that, given the severity of her daughter's condition, this approach is not realistic.

The 45-minute examination was chaotic from start to finish, Anim says. Her daughter was extremely anxious and kept asking the doctor if he was going to take a blood test. She refused to sit down and hopped on and off the medical examining couch when the doctor was talking to her. Anim points to a line in the partly computer-generated report which notes "client was able to sit on a chair with a back for 45 minutes".

"The whole examination was very chaotic and bizarre because she was not co-operating. But in his report he has put that Ruthie sat for 45 minutes. She never sat down for more than three minutes. She was all over the place," she says. "At one point she went to the tap and washed her hands and started spraying the water everywhere. He raised his voice and said 'Stop doing that!' I said no, no, don't speak to her like that. She's got learning difficulties; she doesn't understand."

A few questions the doctor asked, about her daughter's condition and her schooling, made Anim doubt his familiarity with the British care system. He noted in his report that her daughter's speech was normal, although Anim had done most of the speaking. The few questions Ruth managed to respond to were answered inaccurately. "He asked her how old she was and she said 18, despite the fact that she is 27," she says.

A few months after the medical assessment Ruth was called to an interview at the jobcentre to discuss finding work. She went with her mother, who was aghast when she understood why they had been called in. "I said 'Are you having a laugh?'" The jobcentre adviser realised very quickly that a mistake had been made. "We sat down, and every question she asked her, Ruth raised her palms as if she didn't know the answer. She asked 'What day is it?'; Ruthie said Thursday, but it was Tuesday. She asked 'What time is it?'. She said 5.30pm, but it was 2.30pm," she recalls. "Ruth was rummaging through the tray on her desk and being disruptive. She kept saying, 'What's your name?'"

"They said she must come every three weeks to show that she is actively seeking work," Anim says; but the adviser also told her that she could appeal against the decision. "It only took her 10 minutes to realise that the decision was wrong."

Anim spent her summer holiday trying to sort out the problem, marshalling the support of her local MP, Glenda Jackson, and a welfare rights organisation, Brent Association of Disabled People, as well as contacting Atos and the DWP.

The decision caused immense stress to the whole family, she says. "As a nurse I know what effect this has on families. You have to constantly struggle to get the support to meet her basic needs. After all we have gone through, then to be told she needs to look for work. She was totally oblivious to what was going on, as usual, but we felt disbelief, frustration, stress and shock.

"It was a barmy decision. People with learning disabilities need all the support they can get. [They should] not be put in this situation where there is total ignorance about their ability to work, safety and wellbeing."

Although the Royal College of Nursing has no official position on the WCA, Anim is clear that the policy needs urgent reform. "The system needs to be overhauled and reviewed."

The DWP says that it has introduced numerous improvements to the testing process, but charities state that serious problems continue. A report published by Citizens Advice earlier this year found a "worryingly low" level of accuracy in the assessments. The charity, which supports many people who feel they have been wrongly denied benefits through the appeals process, has seen a 71% increase in workload relating to the employment and support allowance (the replacement to incapacity benefit) over the past two years.

Campaigners blame both the design of the policy and the way it has been implemented for the problems. The headquarters of Atos have been repeatedly targeted by disabled protesters, angry at the company's involvement in the assessments, and the company's sponsorship of the Paralympics caused widespread controversy.

The National Audit Office criticised the Department for Work and Pensions in August for not having "sought financial redress for contractor underperformance" and recommended that it "tighten performance requirements with Atos in relation to the quality of medical assessments".

Earlier this year delegates at the BMA conference passed a motion stating that the "inadequate computer-based assessment" performed by Atos had "little regard for the nature or complexity of the needs of long-term sick and disabled persons", and proposed that the WCA should be halted "with immediate effect".

Jane Alltimes, senior policy officer at Mencap, said Ruth's case was not particularly extreme. Mencap has submitted recommendations for improvement to the system to the DWP, and is arguing for greater recognition of employers' unwillingness to employ people with learning disabilities. Just 7% of people who receive state support for their learning disabilities are in work.

"The evidence we've seen suggests an assessment process that isn't working for lots of people with a learning disability. An assessment designed to determine a person's 'fitness for work' needs to take into account the realities of the barriers experienced by disabled people in getting a job – things like job availability, the prejudices of employers, the support people need to overcome the barriers they face. The assessment in its current form just doesn't do that."

An Atos Healthcare spokesperson said: "We apologise for any discrepancy in our report and any distress this may have caused. We carry out around 15,000 assessments each week and work hard to provide the DWP with as much detailed information as we can to contribute to them making an accurate decision on benefits."

A DWP spokesperson said: "The work capability assessment is under constant review to ensure it is both fair and effective, and it is in everyone's interest to get the system right. We are committed to help thousands of people move from benefits and back into work while giving unconditional support to those who are most in need."