Tens of thousands of disabled people could have had their disability benefit claims decided on evidence from assessment reports that were of “unacceptable” poor quality, government figures suggest.

The Department for Work and Pensions (DWP) figures suggest that civil servants may have been deciding many personal independence payment (PIP) claims based on information contained in assessment reports that were of such poor quality that they should have been sent back to DWP contractor Atos to “rework”.

DWP and Atos – which carries out PIP assessments on the government’s behalf – have both denied any such inference can be made from the figures passed two weeks ago by the minister for disabled people, Sarah Newton (pictured), to Labour MP Grahame Morris.

But disabled campaigners believe the figures raise fresh concerns about the quality of PIP assessment reports and how DWP decides claims, following years of mounting anger about the way the extra costs benefit is run since it was launched five years ago as a replacement for working-age disability living allowance.

Morris had asked DWP ministers how many PIP assessment reports in each of the last five years had been returned to Atos for “reworking” because they were “deemed unacceptable”.

In another question, he asked how many PIP assessments Atos had carried out every year.

But the figures showed only a tiny proportion of assessment reports were being returned by DWP case managers to Atos for reworking because they were “unacceptable”, with 301 (0.48 per cent of them) returned in 2013-14, 640 (0.18 per cent) in 2014-15, 748 (0.14 per cent) in 2015-16, 1,727 unacceptable reports (0.22 per cent) in 2016-17, and 8,702 (1.14 per cent) in 2017-18.

The figures showed a huge increase in the last two years, but the proportions were still far lower than Atos had admitted to the Commons work and pensions committee last December.

Giving evidence to the committee, Atos said the proportion of PIP assessments graded as “unacceptable” had been as high as 30 per cent at one stage of its contract and was still about five or six per cent.

DWP explained last week that the rates revealed in the committee’s evidence session in December had been the proportion of PIP reports graded as “unacceptable” after an Atos “independent audit”, which was why they were different to the figures released to Morris.

Only a tiny proportion of reports are ever audited.

This suggests that in the last five years, assessment reports of an “unacceptable” quality may have been at times more than 100 times less likely to be picked up by a typical DWP case manager and sent back to be “reworked” than the small number of reports that were audited.

With more than 760,000 Atos assessments taking place in 2017-18 and more than 780,000 in 2016-17, this suggests that tens of thousands of unacceptably poor reports could have slipped through the net and led to unfair decisions to refuse disabled people’s entitlement to PIP.

Both DWP and Atos deny that this is what the figures show.

But DNS has previously spoken to a DWP civil servant working on the PIP “frontline”, who has said that DWP case managers have strict targets for the number of PIP claims they need to process every day, and are quizzed by their superiors if they miss their weekly targets.

He has said they are also “instructed to act on the assessor’s report, given that they are the medical experts”.

This week, he stressed again that case managers are “browbeaten by the ‘you are not medically trained, go with the Assessment Provider’s justification’”, but insisted that case managers “do try to ensure accuracy and will question”.

When asked to explain the discrepancy between the two sets of figures last Friday, DWP originally promised to respond on Monday this week. It finally responded after 4pm yesterday (Wednesday), nearly five days after the original request was submitted.

When it finally issued a statement, DWP argued that its PIP decision-makers did not always return poor quality reports to Atos but were instead “empowered to overturn decisions without further involvement of the Assessment Providers”, while they would “also seek advice and clarification directly from the Assessment Providers without the need for formal re-work”.

A DWP spokeswoman said this meant that its staff had not been basing huge numbers of decisions on unacceptably poor PIP assessment reports.

She also said that “re-work guidance” for its decision makers was revised in September 2017 so that it was consistent with the guidance used by the Atos internal auditors, and “to help improve the quality and accuracy of the information that was the basis of the PIP decisions”.

She added: “The proportion of all reports that are sent back for re-work is very low given the vast numbers of reports produced.

“The vast majority of reports are of a quality that can be used by decision-makers in the first instance.”

But she refused to say by noon today (Thursday) if DWP believed that its decision-makers prevented a similar proportion of PIP claims being decided on “unacceptable” reports as the Atos auditors.

She has also repeatedly failed to explain why the proportion of assessment reports returned by DWP case managers to Atos as “unacceptable” shot up from 0.14 per cent in 2015-16 to 0.22 per cent in 2016-17, and 1.14 per cent in 2017-18, an increase last year of more than 400 per cent.

An Atos spokesman said: “We don’t in any way recognise the interpretation of the data or the conclusions reached by Disability News Service.”

DNS has been investigating claims of widespread dishonesty by PIP assessors – from both Atos and fellow outsourcing giant Capita – for nearly 18 months, and has heard from about 300 claimants who say their PIP assessment reports contained clear lies.

Morris, the MP for Easington, said: “The minister for disabled people is presiding over a systemic failure, which is causing misery and hardship for thousands of vulnerable sick and disabled people.

“DWP are not providing sufficient oversight and scrutiny, with so few reports sent back to Atos for re-work.

“I can see from my casework, and I fear, that thousands of vulnerable people are being denied access to PIP based on substandard reports produced by outsourcing contractor Atos.

“The health assessment process does not work and is a cruel system which harms the health and wellbeing of the sick and disabled.

“There is gross incompetence at every level. The government demonise the sick, viewing them as claimants to be processed, rather than as people in need of support to manage often multiple complex health conditions.

“The system will never be fit for purpose while the government’s motivation is about cost-cutting rather than an individual’s health needs.”

Campaigner John Slater, whose freedom of information work has previously produced crucial data about the DWP’s PIP assessment contracts with Atos and Capita, said the new figures appeared to confirm his suspicions about the audit process.

He said they appeared to show that a significant percentage of unacceptable reports are never spotted and acted on by DWP.

He said: “My personal view is that the DWP is doing all it can to be opaque about the true extent of quality problems with PIP assessment reports.”

Bob Ellard, a member of the national steering group of Disabled People Against Cuts, said: “To the uninitiated, this might sound like simple incompetence by the DWP, but for those with more experience of them will see that this is just one part of the ‘hostile environment’ that they perpetrate towards disabled people and other claimants.

“For them to have the knowledge of such a high number of unacceptable assessments, and yet only rework a small number of them, shows once again deliberate maltreatment of disabled people for whom their benefit entitlements can form a vital lifeline.”

Although there are not yet any statistics to show the levels of “unacceptable” assessment reports by the other PIP assessment provider, Capita, it is likely that similar problems also affect its reports.

In December, the Commons committee heard from Simon Freeman, managing director of Capita’s PIP contract, that at one point, internal audits were showing 60 per cent of its reports were of an “unacceptable” standard, while the current rates were still at nearly seven per cent.