Schools rated outstanding by Ofsted are no more successful at closing the achievement gap between rich and poor students than those judged inadequate, a new research paper suggests.

The similar gap across all types of schools suggests that factors outside of the institutions’ control, rather than any school-related policy or classroom practice, are the main factor affecting results, according to Professor Steve Strand from the University of Oxford.

In schools rated “outstanding”, the gap between the proportion of free school meals pupils receiving five GCSEs at A* to C including English and maths and their peers is 25 percentage points, the same as in those rated “good”, his analysis shows.

There is a similar finding for schools rated “satisfactory/requires improvement” and “inadequate”, where the gap is 22 percentage points.

According to Professor Strand, who is due to present his findings at the British Educational Research Association annual conference tomorrow, the findings suggest that the current school accountability regime - including Ofsted and league tables - is biased against schools in disadvantaged areas.

“Schools do not appear to be the major cause of the FSM [free school meals] gap since there appears to be an FSM gap in nearly all schools,” Professor Strand’s paper says.

“Factors outside the school gates (in the home, wider community or peer groups) are likely to be more influential. For example, children who grow up in poverty may do less well in education because they have parents who are more stressed, less able to afford educational activities and resources and less well-placed to help them with their school work.

“This is not to say that schools should not do everything possible to strive to close the FSM gap, but does indicate that a punitive approach to ‘failing’ schools misconstrues the nature of the problem.”

The paper, Moderators of the FSM achievement gap: being more able or poor in an affluent school, says: “By failing to account for any factors associated with pupil background or the socio-economic composition of the school, current accountability mechanisms such as performance [league] tables and Ofsted inspections are biased against schools serving more disadvantaged intakes.

“These are a disincentive for talented teachers and school leaders to work in more challenging schools.”

The findings come after an analysis by Trevor Burton, the headteacher of Millthorpe School in York, who found a correlation between secondary schools’ Ofsted grades and the prior attainment of their pupils when they were at primary school.

The link was particularly stark in grammar schools, which got a disproportionate number of “outstanding” grades, even though they only accept brighter students.

Related stories:

Is Ofsted’s grading ‘scandalous’?:  31 August 2014

Literacy - Poverty can set the brightest back by three years 31 July 2013