The government has failed to investigate an “incredibly difficult” Sats paper that left children “sobbing” and unable to finish their tests, it has been revealed.

The Standards and Testing Agency (STA), overseen by the Department for Education, had agreed with Ofqual that it would  investigate the 2016 key stage 2 reading test after a quarter of pupils did not complete their papers.

However, now Ofqual - the exams regulator - has revealed that, “regrettably”, the STA has not yet managed to carry out the research, owing to “lack of sufficient resource”.

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The test, described by teachers as “incredibly difficult”, “ridiculous” and “bloody tough”, was the first of the reformed Sats introduced in 2016, and was sat by 600,000 children.

In 2017, Ofqual concluded that the paper may have been “unduly hard” after using test data from the STA, as well as independent research, its own investigation into the tests and comments published on social media to review the exam.

It said that there were a number of “important questions” for the STA, including whether pupils were given enough time to complete the reading test; if concerns about this could have been flagged up earlier during the development process; and how potential biases against certain groups of pupils - such as those with SEND - could be better identified.

But the exams watchdog has since found that the STA is yet to research data that may provide an insight into why so many pupils failed to finish their papers.

In its National Assessments Regulation Annual Report 2019 published today, the regulator said: “In response to our review of the 2016 reading test, STA committed to a number of actions, the majority of which are either on track or completed (see 2018 report).

“However, while STA remains committed to researching data to understand more about why the 2016 reading test was not finished by 25 per cent of pupils, regrettably, it has not yet been able to carry this out due to lack of sufficient resource.

“We will continue to monitor and report on STA’s progress towards this commitment.”

The Sats had been made tougher in 2016 to reflect the new curriculum. The tests included questions designed to “stretch” the highest achieving pupils, who in previous years could have taken a separate test.

When the results were published, just two-thirds of pupils had reached the expected standard in reading. 

Voicing their concerns on the Tes forums in 2016, some teachers claimed that the paper was better suited to 15-year-olds than pupils aged 10 and 11.

One said: “That was, without doubt, the hardest reading test I’ve ever seen. Unbelievable. I’m so angry right now.

“That has completely demoralised a number of children in my class. It wasn’t even like the sample paper they released. Much harder.”

Another added: “The questions were ridiculously hard from the start and I had a child in tears within five minutes, because in her words, ‘I don’t understand the questions’. This wasn’t even a less able child.”

A third teacher said: “Dreadful! Children who had succeeded previously in the ‘sample’ test were sobbing! More able not finishing. If ever a test was set up to prepare children to fail, this was it.”

The DfE has been approached for comment.