The government must change the way benefits are assessed if its welfare reform plans are to succeed, the Citizens Advice Bureau has warned.

The charity said that the process used to decide who qualifies for disability and incapacity benefits is "deeply flawed". So many wrong decisions are made, the charity said, that more than six out of ten are overturned on appeal.

The way medical assessments were carried out and the weight they are given was largely blamed for the problem.

Citizens Advice said that the Department of Work and Pensions relied too heavily on the findings of these tests, rather than evidence from claimants' own GPs or other practitioners.

The problems with the medical assessments included inaccurate reports, doctors wrongly reporting what people have told them or underestimating the severity of people's disabilities. Many CAB clients reported feeling humiliated, intimidated and rushed by examining doctors, who were also described as often rude, insensitive, aggressive and dismissive.

People with mental health problems often fared particularly badly during these examinations, the charity said. In one case, a woman with severe mental health problems lost her benefit and was forced to live on £39 a week for six months, after an examining doctor said she "didn't look mental", the report said.

The CAB said that those whose claim is stopped or refused faced the choice of claiming jobseeker's allowance of £56.20 per week or, if they decide to appeal, income support reduced by 20%. This means they could be left with as little as £45 per week to live on for several months while they wait for their appeal to be heard.

Citizens Advice senior social policy officer John Wheatley said: "Getting benefit decisions right and getting them right first time is the key to ensuring that vulnerable people get the money that is rightfully theirs and that public money is not wasted.

"Things have got to change. There has to be a vast improvement in the quality of medical assessments and decision-making and this has to happen before the government goes ahead with its welfare reform plans.

"Our evidence shows that the current system is not working either for the people claiming benefits or for the DWP and the quality of medical assessments and decision-making is completely unacceptable."

However, the Department for Work and Pensions claimed that their surveys showed that the number of dissatisfied clients was small. A spokesperson also said that the department was expected to address problems with medical assessments, in order to provide help and support for people to return to work.

The CAB has called for an urgent review of the decision-making and appeals processes for all incapacity and disability benefits.

The charity also said that a mental health champion should be appointed to ensure that the system deals better with cases involving people with mental health problems.

(KMcA/GB)