The number of children who receive free school meals (FSM) is a misleading indicator of a school’s socio-economic composition, Catholic academics have said.

The figure is often used by campaigners to accuse Catholic schools of not taking a fair share of poor pupils.

But researchers at St Mary’s University, Twickenham have shown that data from the Department for Education only inc­lude the number of children actually receiving free meals, rather than all those who are eligible but may not have signed up for them.