Exam boards have been criticised by the head of Ofqual for oversights on their papers, where pupils were tested on topics they had been told were ruled out of the paper or sat papers that included mistakes.

Exam board AQA has apologised twice during this year’s GCSE and A-level exam period following complaints that a 30-mark question in its A-level law exam had not been included as part of the advance notice of exam topics given to pupils this year to mitigate the impact of the pandemic.

On Friday, the board apologised to law students for the “confusion and stress” they had been caused after questions on nuisance were included in the paper despite not appearing in the list of topics pupils were informed in advance to revise.

AQA had told pupils that “higher tariff questions” – those carrying more marks – would draw on the listed topics given to pupils before their exam.

It apologised last week after its GCSE physics paper included a question on a topic that had been ruled out in the advance information.

Another exam board, Edexcel, was forced to apologise over an error in its GCSE geography paper which labelled Gabon as the Democratic Republic of Congo on a map of Africa.

Jo Saxton, Ofqual’s chief regulator, told the Confederation of School Trusts’ annual conference on Friday that “the package of support in place for students for this year’s summer series, all intended to make the path back to pre-pandemic arrangements as smooth as possible” had had some “real bumps in this road”.

She added: “I absolutely understand the distress that mistakes in advance information and exam papers cause.”

Dr Saxton added that students had “welcomed” exam aids and formulae sheets, which she said had “taken the stress off of their shoulders”.

Pupils have had advance information about the topics covered in their exams alongside formulae sheets in some subjects to help adjust for the impact of the pandemic on their learning this year.

But she added: “They love the idea of the advance information, but the reality is they found navigating it in many cases just one other thing to think about.”

Dr Saxton said that the 2022 results would be “the most generously graded” set of exams on record but that results would be lower than in 2021, when teacher-assessed grades were awarded for GCSEs and A-levels.

An AQA spokesperson said: “One of the aims of advance information is that it shouldn’t narrow teaching and learning, so we couldn’t list all the topics on the exam paper.

“Although we advised students to revise all topics and included the focus of one of the two 30-mark questions, we appreciate that many students expected us to include the focus of both questions – especially in light of guidance we gave before we released the advance information.

“We didn’t mean to cause any confusion or stress for students and we’re sorry that we did. The fairest way to address this is for us to look at how students performed on this paper after we’ve marked it, and we’ll take any action necessary to protect them.”