The “toxic” government contractor Atos has been accused of trying to create a smokescreen to hide its past failures and “appalling reputation”, after quietly announcing that it is changing the name of its disability benefit assessment arm.

The company – blamed by many disabled people for repeated, serious and harmful failings in the way it has carried out assessments – has told “stakeholders” that its Atos Healthcare brand has now been renamed Independent Assessment Services.

The company carries out assessments for the government’s new personal independence payment (PIP) – which is gradually replacing working-age disability living allowance – across London, the south and north of England, and Scotland.

Only this week, Atos has been forced to launch an investigation after Disability News Service (DNS) reported how a disabled women said she was left to sit in her own urine for nearly two hours after her plight was ignored by one of its PIP assessors.

This followed a major DNS investigation that uncovered scores of cases in which claimants described how Atos assessors – and those from the government’s other PIP assessment contractor, Capita – produced dishonest reports after carrying out face-to-face assessments.

Atos was previously responsible for delivering the even more controversial work capability assessment (WCA) – a process that researchers, activists and the Equality and Human Rights Commission all concluded had caused significant harm and distress to many of those who were assessed, and was also linked to deaths of claimants – before it quit the government contract in 2014.

Disabled activist Gail Ward, from Black Triangle, accused Atos of trying to create a “smokescreen” to cover up its “incompetence” in carrying out assessments.

She said: “Atos can rebrand all they wish. We will still call them Atos at every opportunity.”

She said Atos’s actions had left many disabled people trapped in their own homes, after losing their entitlement to PIP, with many having to return their Motability vehicles.

And she said many grassroots campaigners were receiving requests for help in dealing with “fabrication of facts” in Atos PIP assessment reports, which had caused many sick and disabled people “a great deal of distress”.

Her Black Triangle colleague John McArdle added: “Atos has not changed its spots. It is still working as the government’s henchman.

“We see the same litany of wrongdoing that has been reported by DNS, with fraudulent reports and catastrophic harm being caused to disabled people.”

He said the attempt to rebrand itself as a “respectable organisation” would fail, and added: “Atos is infamous for carrying out systematic abuse of the fundamental human rights of disabled people.

“It is a toxic brand and has become a byword for corporate wrongdoing worldwide.”

One PIP claimant who has previously given evidence as part of the DNS investigation into dishonest assessment reports said she was “not surprised” at the Atos rebranding.

She was assessed by an Atos nurse, who produced a “fictional” assessment report that was “totally inaccurate”, including a description of a medical examination that was a “total fabrication”.

She said Atos had an “appalling reputation”, and added: “It doesn’t matter what they call themselves, the same people are running the company and the same people are doing the assessments.”

Atos has told stakeholders that it carried out the rebranding to make it “clear that we are ‘independent’ providers, distinct from DWP” and because the new name explains more clearly the service it delivers.

It also claims that the involvement of Atos will still be clear in the branding of the new name, but its new website shows Independent Assessment Services with the words “delivered by Atos” only in tiny letters underneath.

An Atos UK spokesman said: “We believe the new name better reflects the role the company undertakes on behalf of the DWP and the assessment work the company carries out.

“The change also follows the first independent review by Paul Gray which recommended a number of changes to claimant communications*.

“It has been planned and undertaken in consultation with a number of disability representative organisations, who have been supportive and have welcomed the change.”

Both of the two disability organisations Atos said had supported the name change have told DNS that they did no such thing.

The Atos spokesman added: “The change has no effect on any policies and procedures, or the way in which assessments for PIP are carried out.

“All claimants are being advised to continue to attend assessment appointments and respond to communications in the normal manner.”

*Among its recommendations, the review highlighted how “the branding of letters for different parts of the process emphasises the different organisations involved rather than highlighting that they are all part of what should be an integrated PIP journey.

“This practice also makes the development of a blame culture between different parts of the supply chain all too easy.”

Gray recommended that the assessment process should be made “more integrated under common branding”, but there was no suggestion that Atos Healthcare itself should change its name.