A measure used by universities to spot socio-economic disadvantage is “not effective” at identifying poorer students who need support, a report suggests.

Nearly half (48%) of students classified as “disadvantaged” under the Polar measure – which assesses whether a young person comes from an area with low participation in higher education- are not from a low-income background, according to the Sutton Trust report.

The Polar (Participation of Local Areas) measure is biased against certain groups – including BAME students, those living in London and those with young mothers, the study suggested.

The charity is calling on the Government to give universities access to data on free school meal (FSM) eligibility so they can move away from the Polar measure and make the fairest admissions decisions.

It says the Office for Students (OfS) should review Polar as it is a “poor” indicator of family income.

It is of particular concern that local area indicators such as Polar are biased against some groups like young people from BAME backgrounds, or those that live in rented accommodation

The Sutton Trust report, which looked at data from more than 7,000 young people in the Millennium Cohort Study, explored how different measures of disadvantage relate to long-term family income.

Of the nine measures examined, the research concluded the most effective indicator of childhood poverty is the number of years a child has been eligible for FSMs.

But universities commonly use Polar data in their contextual admissions processes as they do not have access to verified data on FSM eligibility.

The Polar measure looks at a young person’s local area and assigns them into one of five groups, depending on the proportion of young people in their area that go to university.

The quintiles are ranked from the areas with the lowest participation rates – the most disadvantaged – to the areas with the highest participation rates, considered the most advantaged.

The report comes as elite universities are under increased pressure to widen access to their courses and make sure students from poorer backgrounds are not put off from applying.

Oxford University released figures this week which showed the proportion of British students from areas with low progression to higher education admitted last year rose to 15.6%.

But the Sutton Trust report concluded the Polar tool contains the greatest biases against certain groups

The charity is calling for greater transparency and consistency from universities and employers when communicating how contextual data is used and how certain markers are used.

The OfS requires universities and colleges to consider Polar alongside other measures of disadvantage when they are drawing up the plans and targets they must agree with the OfS

Sir Peter Lampl, founder and chairman of the Sutton Trust, said: “In order to widen access fairly and effectively, universities need to know which students would benefit most from outreach programmes and contextual offers.

“But as today’s research shows, the measures they use are not as effective as they should be at identifying low-income students. They miss out some who deserve support while inaccurately flagging others.

“It is of particular concern that local area indicators such as Polar are biased against some groups like young people from BAME backgrounds, or those that live in rented accommodation.

“As a practical next step, the Government should make sure that universities have access to data on free school meal eligibility, and target support where it is most needed.”

A Universities UK (UUK) spokeswoman said: “As recommended by UUK’s fair admissions review last year, the Government must facilitate access to free school meals data at the point of students applying to university, to help bolster efforts to widen access and drive social mobility.”

On Friday, Lord Wharton, the new chair of the OfS, will highlight universities’ key role in levelling up access to higher education for students from all backgrounds in a speech to vice-chancellors.

Addressing the UUK members’ meeting, Lord Wharton will warn “too many people are still locked out of higher education”.

He will say: “Universities, working with schools, have a crucial role to play here – they need to continue to reach out – especially to those towns and coastal communities where people feel forgotten – and to show people there that university is for them too.”

But Lord Wharton will add: “Let me be clear though. Broadening access to university cannot be done by lowering standards. I do not accept the argument that levelling up can involve any reduction in the academic excellence and rigour of which our higher education sector is rightly proud.”

On the Sutton Trust study, an OfS spokesman said: “Polar is used to measure areas of under-representation in higher education, and its use helps the OfS to fulfil our objectives around fair access and participation.

“Polar shows entrenched patterns of under-representation, highlighting neighbourhoods where very few people go into university.

“This is crucial when we consider how best to improve successful higher education participation in the places across the country where people feel they have been left behind.”

He added: “The OfS requires universities and colleges to consider Polar alongside other measures of disadvantage when they are drawing up the plans and targets they must agree with the OfS.

“We are developing new measures which consider a range of factors – including identity and place as well as income – and will be deploying these as we engage with universities and colleges on their access and participation plans in the coming years.”