SCOTLAND’S schools were in the dock this week following the publication of an international survey of pupil attainment.

According to the 2015 Programme for International Student Assessment (Pisa) pupil scores for science and reading declined while those for maths stagnated.

The report concluded that Scotland’s performance was now “average” in the developed world compared to being “above average” in 2000 when the survey of 15-year-olds began.

As expected, Scotland’s slide was seized upon by opposition politicians who accused the SNP government of a “decade of failure” in education.

Because First Minister Nicola Sturgeon has made closing the school attainment gap the cornerstone of her administration she was also forced to defend her record in Holyrood.

Hearing alternative voices in this high volume black and white narrative is difficult, but writing in The Herald on Wednesday Dr Alan Britton, from Glasgow University’s School of Education, was one of the few to put the spotlight on Pisa itself.

He believes Pisa provides a flawed basis on which to draw too many hard and fast conclusions because it offers only a snapshot of change over a three year period amongst a sample of just 3,000 pupils. “It tells us little or nothing about why things have changed,” he adds.

In fact, the survey coincided with a time when teachers were raising significant concerns about the roll-out of Curriculum for Excellence reforms with accusations of burdensome bureaucracy, confusion about its aims and over-assessment.

Additional pressures on schools were created by cuts to funding which have impacted on key support staff such as classroom assistants.

Dr Britton’s reservations about Pisa are mirrored by a number of other key figures in recent years both in the UK and abroad.

Writing in the Daily Telegraph in 2013, Martin Stephen, the former headmaster of the private St Paul’s School, in London, revealed that during a year-long research project into how the world educates its most able children “several representatives from one of the high-scoring countries confessed they taught to the test to achieve a good score”.

In 2014 Professor Yong Zhao, from the University of Oregon, noted that Pisa pushed schools to conform to basic academic abilities without valuing the skills needed in the 21st century.

He said: “Asian countries performed much better, but a homogeneous workforce is not required for a successful future. We should ignore Pisa.”

That is not the approach taken by John Swinney, the Education Secretary, who got his retaliation in early by arguing Pisa was a sign to press ahead with even more radical reform of the kind favoured by the SNP - namely standardised testing, new educational regions and a shifting of power from councils to headteachers.

Interestingly, a paper by Oxford University’s Centre for Educational Assessment in 2011 noted: “It is striking that Pisa seems to have been used for sabre-rattling political rhetoric to drive through educational reforms.”