Grammar school selection has become a “Wild West”, according to a respected education figure who designed 11-plus tests.

Professor Robert Coe, a former maths teacher, was part of an attempt to create “tutor-proof” tests when he worked at Centre for Evaluation and Monitoring (CEM) in Durham.

But he said there was too little quality control or transparency over the tests.

He told Tes: “I do think it’s a bit of a Wild West in which individual schools or groups of schools can basically commission any kind of test or selection process they like and some are a lot better than others.

“There is no quality driver, no incentive for high-quality processes in the system. That’s not to say that many grammar schools do not have high-quality processes - and they want that and they prioritise that - but not all do.”

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Professor Coe, who now works for training and research provider Evidence Based Education, but whose 11-plus test is still being used by grammar schools, said the Covid pandemic had probably made “a bad situation slightly worse” when it comes to the performance of disadvantaged pupils taking grammar school entrance exams.

He is one of more than twenty leading educationalists to have signed a letter to education secretary Gavin Williamson calling for the same “transparency” in 11-plus exams as is afforded to Sats and GCSEs.

Grammar schools: Fears over the number of disadvantaged pupils passing the 11-plus 

And he said the pandemic had created “a particular problem this year” because of the disruption to normal kinds of support for taking the tests, including the extra support that many primary schools put on, as well as the logistics of pupils going into schools to sit the tests.

The letter, signed by more than a dozen university professors, states that there are currently more than 70 different 11-plus exams taken by more than 100,000 pupils every year, yet there is no central data available on how many pupils sit the tests every year and how many pass, including how many disadvantaged pupils pass.

Dr Nuala Burgess, chair of anti-selection campaign group Comprehensive Future, who initiated the letter, said: “Of particular concern to us is that there is no way of knowing how poorer children fared in the tests taken last autumn, in the midst of the Covid pandemic. It seems highly likely that thousands of children’s 11-plus chances were negatively impacted by disrupted learning.

“Incredibly, grammar schools are now planning their September 2021 tests - as if the world of education has not been turned upside down by a global pandemic. These schools are under no obligation to check how disadvantaged pupils performed in last year’s test and appear unconcerned by the severe challenges they will have faced.”

The Grammar School Heads’ Association (GSHA) says the admission tests need to be different for different schools because they are “fulfilling different purposes”, and that it “simply doesn’t make any sense” to categorise them as a public exam in the same way as Sats or GSCEs.

GSHA chief executive officer Mark Fenton said: “Selection tests for grammar schools vary across the country because grammar schools are not all the same. For historical reasons, selective schools admit widely variable percentages of the children in their area. Where just one or two grammar schools remain to serve a wide area, they might only be able to admit 5 per cent of children, whereas in wholly selective areas such as Kent the proportion is 25 per cent.”

He added: “Adding the results of different tests which cannot sensibly be compared with each other to the National Pupil Database would invite wholly misleading comparisons between groups of children.”

A DfE spokesperson said: “It is for individual schools’ admission authorities to determine their process for admission, including the content of the selection test and the required standard for admission.

“There are already protections within the system to ensure admission arrangements are fair without seeking further data from schools and local authorities.”