Comparable Outcomes: Scourge or Scapegoat?

25 November 2016

An approach used to set GCSE and A Level grade boundaries in the UK does not prevent schools from demonstrating improvement to the education watchdog Ofsted, according to research published today by Cambridge Assessment.

Principal Research Officer Tom Benton found that the “comparable outcomes” approach to grade boundary setting in fact has a very limited impact on individual schools.

First implemented by the exams regulator Ofqual in 2011, comparable outcomes is widely credited with tackling grade inflation. It works by pegging GCSE and A Level results to the performance of students in previous years. But teaching unions have argued that the approach comes at the expense of schools, which are required to demonstrate improvement year-on-year but are unable to do so under the “yoke” of comparable outcomes. 

In his paper Comparable Outcomes: Scourge or Scapegoat? Dr Benton acknowledges that the policy could mean that system improvement is not always recognised. However, individual schools and colleges are able to demonstrate improvement because in most cases actively controlling grade inflation using comparable outcomes leads to grade boundaries that are no more than one mark more severe than they would have been in any case. In the context of the usual amounts of year-on-year variation that are seen in schools’ results, the effect of lowering grade boundaries by a single mark is very small.

In his analysis, Dr Benton also argues that Ofsted does not necessarily require schools to demonstrate improved exam performance year-on-year. In fact, one in four schools rated as ‘good’ by the schools inspectorate had decreased their performance in the run-up to the inspection, while almost half rated as ‘requiring improvement’ had improved their results.

Tim Oates, Group Director of Assessment Research and Development at Cambridge Assessment, said:

“Comparable Outcomes is one method of a number to set, monitor and maintain standards. It has particular value when managing periods of change in qualifications, but like so many methods it is no silver bullet and has shortcomings as well as benefits.

“As an international organisation which uses a very wide range of statistical and other measures to monitor and maintain standards, we are agnostic about Comparable Outcomes. We recognise however that there are concerns about whether it prevents schools from demonstrating improvement, so we undertook the research to find out the real situation.”

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