Schools in Stevenage have taken the decision not to publish their overall GCSE performance on results day in August because of the potential “confusion” caused by the new league table system known as Progress 8.

Headteachers at all six Stevenage secondary schools have stated that the new system will make it impossible for schools to compare performance with previous years and with other schools until official league tables are published later in the year.

The new system – which was rolled out nationwide this academic year – means instead of secondary schools being ranked on the proportion of pupils gaining C grades or higher in five GCSE subjects including English and maths, they will be judged on how much progress pupils have made since Key Stage 2.

There is huge debate about whether it is fairer to pupils or not, but it is vastly more difficult to calculate.

As part of the new system, GCSEs will be graded from 1 to 9, with 9 being the highest – replacing the old A*-G scoresheet. But only English and maths are being scored in the new way this year, with the changeover of other subjects staggered until 2019.

Marriotts head Beth Honnor issued a statement on behalf of the Stevenage secondary school headteachers which said: “This year there have been many changes in how students in Year 11 are assessed in their GCSEs.

“This summer is the first time students sat the new English and maths GCSE. Throughout the year schools across the country have struggled to predict and assess what students will achieve as no grade boundaries were in place.

“The new system has led to confusion for students, parents and schools alike.

“With these national changes, year-on-year comparisons of attainment are not appropriate and headline progress measures will be unavailable until the official performance tables are released.”

She added: “As head, we continue to work hard in our own schools. and together as a family of schools, to raise achievement and improve the life chances of every single student in our care. This year we want to celebrate the success of every student.”

It follows a decision made by schools in North Herts two years ago not to publish overall results so they could also focus on “celebrating individual success”.