The performance gap between poorer pupils in northern secondaries and their counterparts in London, on the Department for Education headline accountability measure, can be almost entirely explained by demography rather than school effectiveness, a new analysis reveals.

The research, by Education Datalab, comes after standards in northern schools have faced sustained criticism in recent weeks.

It shows that more than half (58.5 per cent) of the Progress 8 gap between disadvantaged pupils in the north and London can be explained by the characteristics of pupils – such as their ethnicity and first language – and school characteristics, such as the proportion of pupils entitled to free school meals.

More than a quarter (26.2 per cent) of the gap is related to pupil attainment at key stage 2, the analysis finds.

And another 12.3 per cent is down to the fact that London pupils are typically entered for more subjects that count towards the Progress 8 target.

Northern schools gap

In 2016, disadvantaged pupils in London averaged 9.6 entries, whereas those in the North averaged 9.4 entries. The maximum is 10, factoring in the double-counting of English and maths.

In a blog, Mike Treadaway, associate research fellow at Education Datalab states: "The difference of 0.2 entries might look small, but it accounts for around 0.8 points difference in the Attainment 8 score."

So 97 per cent of the Progress 8 gap between the two regions has nothing to do with actual school performance.

Mr Treadaway concludes: "All of this suggests that attainment gaps between London and the North are more a reflection of the areas that they serve than the effectiveness of the schools in each region."

Political priority

The findings follow a recent report by the Northern Powerhouse Partnership thinktank that showed disadvantaged pupils in the north have an average Attainment 8 score that is 6.5 points lower than that of disadvantaged pupils in London.

The GCSE grades achieved by deprived pupils in the North are on average nearly a full grade lower than those gained by children in the rest of England, it found.

Improving schools in the North of England should therefore be "at the top of the intray" for education secretary Damian Hinds, the thinktank said.

Mr Treadaway's findings are based on Progress 8 scores which put Attainment 8 results into context by factoring in prior attainment when comparing how pupils have performed in eight GCSEs.

He told Tes: "The main message is, when you take a lot of the other factors into account [related to pupil and school characteristics], the differences are pretty thin."

His blog states: "We might, therefore, conclude that the recommendations for additional funding made in the Northern Powerhouse Partnership report are justified – but that they are justified more on the basis of demographic differences rather than differences in school effectiveness."

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