Multi-academy trusts (Mats) in England have significantly higher annual turnover of classroom teachers at secondary level than schools maintained by local authorities, analysis has found.
Teacher recruitment and retention is a challenge facing all schools but the problem is particularly acute in larger Mats where annual teacher turnover stands at 19.5% on average compared with just 14.4% at the median local authority, the research showed.
Larger Mats, with 10 or more schools, also have higher rates of persistent pupil absence, suspension and unexplained departures than smaller Mats and local authority schools on average, according to the Education Policy Institute (EPI) analysis.
The findings are the result of a tool developed by the EPI to compare the performance of academy trusts, local authorities, federations and dioceses across a range of performance indicators.
The school system in England has undergone rapid and far-reaching change since Labour introduced academies in 2002 as a means of raising educational standards in disadvantaged communities and areas of low performance.
Academies are state schools that are not controlled by the local authority, but are usually in Mats, which are not-for-profit companies that run more than one academy.
The rollout of the academies programme has escalated under the Conservatives and now eight out of 10 state-funded secondary schools are academies or free schools, while two out of five primary schools have converted to academies.
While the EPI research is cautious about suggesting causality, on teacher retention it says that at secondary level, high teacher turnover is negatively correlated with overall attainment and post-16 destinations.
It adds: “Some staff turnover is … necessary and desirable, but excessively high turnover can be disruptive to learning and may imply staff are unhappy with the working conditions in their current role.”
On persistent pupil absence, suspensions and unexplained exits, the EPI notes by way of context that larger Mats admit greater rates of disadvantaged pupils and help them to make greater progress.
Another significant area the EPI has investigated is the financial health of different groups of schools. It found in the case of secondary schools, Mats are almost three times as likely to have positive in-year balances than other school groups. At primary level, Mats are twice as likely.
The EPI does not reach a conclusion about which school structure is best. It says: “This report shows there is no identifiable general optimal organisational structure for school groups. We cannot conclude that, based on performance alone, the Mat structure should be preferred to the local authority model, or vice versa.”
Daniel Kebede, general secretary of the National Education Union, said it was commonplace for students to be taught by three different, often non-specialist teachers in a given subject within a year.
“That is why the recruitment and retention crisis is such an urgent issue for the present and any future government,” he said.
“The EPI highlights that this problem is even greater within multi-academy trusts, which is yet further evidence that the obsession with forcing schools into trusts has nothing to do with what is best for education.
“There has been a fundamental failure by successive Conservative governments to make teaching attractive and paid well enough for people to stay. The expansion of academies has been at the heart of this failure.”
Louis Hodge, associate director for school system and performance at the EPI, said: “With large increases in academisation over the last decade, an increasing number of schools are now working as part of wider groups and networks.
“Yet our understanding of the relative strengths and weaknesses of different groups has, to date, been patchy and inconclusive.
“This new research provides a strong foundation on which to build a more rounded understanding of how school groups in England are performing.”
A spokesperson for the Department for Education said: “As the report highlights, there are also positive drivers to teacher turnover. Many teachers leave their current roles due to promotion and move between schools within the same trust.”
“We now have more teachers than ever before, with over 468,000 teachers in the workforce, a 27,000 increase on 2010.”
