"There will be no losers," Iain Duncan Smith said of his Universal Credit programme in November 2010. But a commission led by Paralympian Tanni Grey-Thompson (interviewed earlier this year by the NS) has found that there will, in fact, be 450,000 - all of them disabled.

Its report, based on surveys of 3,500 disabled people and their families, warns that 100,000 disabled children stand to lose up to £28 a week; 230,000 severely disabled people who do not have another adult to assist them are at risk of losing £28-£58 a week; and up to 116,000 disabled people who work could lose £40 a week. If true, and the government has denounced the study as "irresponsible scaremongering", Duncan Smith's vow to "make work pay" will ring hollow for thousands of people.

The report, Holes in the Safety Net: the impact of universal credit on disabled people and their families, is backed by The Children's Society, Citizens Advice and Disability Rights UK. Here's what Grey-Thompson, who shares the title of Britain's most successful Paralympian with cyclist Sarah Storey, had to say about it.

The findings of this report do not make easy reading. The clear message is that many households with disabled people are already struggling to keep their heads above water. Reducing support for families with disabled children, disabled people who are living alone, families with young carers and disabled people in work risk driving many over the edge in future.

Labour has responded by reaffirming its call for the government to delay the introduction of Universal Credit by a year and one wouldn't be surprised if Ed Miliband chooses to quiz David Cameron on this subject at today's PMQs. Shadow work and pensions secretary Liam Byrne said: "This report is another nail in the coffin for David Cameron's claims we are all in this together. The PM tried to hide it in the Commons, but this report lays bare the truth that he is snatching up to £1,400 from 100,000 disabled children yet offering a huge tax cut to millionaires. Disabled people and their families are being forced to pick up the tab for the government's shambolic mismanagement of our economy."

For the record, the Department for Work and Pensions described the report as "highly selective" and accused the commission of "highly selective". A spokeswoman said: "The truth is we inherited a system of disability support which is a tangled mess of elements, premiums and add-ons which is highly prone to error and baffling for disabled people themselves.

"Our reforms will create a simpler and fairer system with aligned levels of support for adults and children. More importantly, there will be no cash losers in the rollout of Universal Credit.

"In fact, hundreds of thousands of disabled adults and children will actually receive more support than now, including paying a higher rate of support for all children who are registered blind."

Laudable words, but the government will need to do much more to convince charities that the disabled, rightly viewed as the most worthy recipients of welfare by the public, will not lose out.