The “simplistic nature” of Progress 8 means that league tables reward the wrong secondary schools, according to the authors of new research.

The University of Bristol study, published on the day the DfE releases secondary school performance data, has sparked renewed claims from heads that league tables have lost their credibility.

The study, by George Leckie and Harvey Goldstein, examines 2016 data from all 3,098 state-maintained secondary schools in England.

It combines Progress 8 information with information on pupils’ age, gender, ethnicity, special educational needs, free school meal eligibility, deprivation and whether they speak English as an additional language.

It finds that a fifth of schools saw their national league table position change by over 500 places, and 40 per cent of schools currently judged to be underperforming would no longer fall into this category.

Dr Leckie said: “By factoring in vital information about a pupil’s background, we have seen a dramatic change in the league tables.

“This leads to very different interpretations and conclusions about education in England.

“It seems clear from our results that the higher the proportion of disadvantaged pupils in a school, the more it will effectively be punished for the national underperformance of these pupil groups.

“On the flip side, other schools are rewarded merely for teaching educationally advantaged intakes.”

The findings echo concerns raised ahead of the introduction of Progress 8, and since.

Dr Leckie added: “The Department for Education’s decision to ignore pupil background when comparing schools is in stark contrast to both the academic literature and feedback from teachers.

“At the moment, the simplistic nature of Progress 8 as a measure places too much emphasis on schools rather than the government or society as a whole.”

Paul Whiteman, general secretary of the NAHT headteachers’ union, said: “League tables have lost their credibility”.

He added: “Ultimately, we have to move away from data.

“Everyone understands that test and exam scores are only part of the picture when judging a pupil’s performance or a school’s effectiveness, so we should stop using them on their own.”

A DfE spokesperson said: “We publish a wide range of performance data - including Progress 8 scores and what pupils go on to do after school or college - to help parents decide on a school for their children and for schools to measure their performance. We do not put schools into league tables.

“Our school accountability measures reflect our high expectations for all pupils, whatever their background.

“Progress 8 takes prior attainment into account and rewards schools for the progress made by all their pupils, not just those at particular grade thresholds.”