A fifth of Scottish schools have not been inspected for at least a decade, it has emerged.

The schools inspectorate has revealed, following a Tes Scotland investigation, that three schools have not had an inspection since 2002, some 16 years ago.

Concerns have been growing in Scotland for some time about the frequency of school inspection.

Education Scotland moved away from undertaking inspections on a cyclical basis in 2008 - inspecting primary schools at least once every seven years and secondary schools at least once every six years - to look instead at a sample of Scottish schools every year.

In the seven-year period between 2009-10 and 2016-17 the number of inspections being carried out dropped by 60 per cent - from 403 to 161. 

However, until now there has been no clear picture nationally about exactly how long Scottish schools are going without an inspector calling.

The figures revealed today have taken almost a year to obtain using freedom of information legislation and were only released following an application from Tes Scotland to the information commissioner.  

Iain Gray, education spokesman for Scottish Labour, said the findings combined the Scottish government’s dual “failings on transparency and mismanagement of our schools”.

The SNP had “diverted resources away from inspection” but tried to hide the scale of that, he said. 

He continued: “This government is perfectly prepared to subject five-year-olds to high stakes tests in the name of “standards”, while letting the established inspection regime wither. 

“It is clear that the inspectorate was not so much merged into Education Scotland, but disappeared into it.”

The Scottish Conservative education spokeswoman Liz Smith said inspection was a vital tool for measuring school’s success and it was “not right that pupils can go through all the years or primary or all the years of secondary without their school being inspected”.

She reiterated her call for the inspectorate to be “entirely separate from Education Scotland”

In response to a previous Tes Scotland freedom of information request attempting to uncover the number of Scottish schools that had been without an inspection for a decade - dating back to August last year - Education Scotland said that records of inspection prior to 2008 had been deleted.  

However, when questioned in the Scottish parliament by Labour’s Iain Gray about the revelation, the education secretary John Swinney said: “Education Scotland retains the ability to see when a school was last inspected by referring to paper-based records for each school.”

Now - for the first time - that information has been pulled together.

It shows that 474 of Scotland’s 2,514 primaries, secondaries and special schools have not been inspected for 10 years or more.

The three identified as not having been inspected since 2002 include Canna Primary in Highland; Sandwick Junior High in Shetland, and Back School in the Western Isles.

A further three schools have not been inspected since 2003: Greenview Learning Centre in Glasgow which is a special school; Hawick High in the Scottish Borders and St Joseph’s Primary in East Dunbartonshire.

Twelve schools were last inspected in 2004; 52 were last inspected in 2005; 118 last had an inspector call in 2006; 151 were last inspected in 2007 and 135 were last inspected in the first six months of 2008.

Education Scotland said last year it planned to increase the number of inspections it carried out. It said that as of April (2018) it would be carrying out 250 inspections a year.

 An Education Scotland spokesman added inspection was only one aspect of the scrutiny work under taken by the body and that Scottish schools were inspected using “a sampling approach rather than a cyclical model”.

He said that the body was in the process of recruiting the addition inspectors and support staff “to support our commitment to enhanced inspection activity”.

The spokesman continued: “Education Scotland continues to place a high priority on our crucial role in inspecting schools across Scotland. Inspection supports improvement and provides assurance on quality and improvement in Scottish education. In carrying out our duties we operate independently and impartially.”

 A Scottish Government spokeswoman said inspection was raising standards in schools. However she added that there was “a need to increase the total number of inspections each year” and inspection was set to increase by a third.