The number of inspectors in Scotland has fallen from 80 to 66 since the SNP came to power in 2007, according to the Scottish Conservatives, who got the figures released in a parliamentary written answer.
Statistics uncovered by the Tories last month that showed inspections in Scotland had fallen drastically over the past decade, from 491 in 2004-05 to 148 in 2015-16 – a drop of 70 per cent.
At the current rate, it would take 19 years to get round every school in the country, said Ruth Davidson (pictured), leader of the Scottish Conservatives.
Education Scotland, which incorporates HM Inspectorate of Schools, said the drop was partly down to a deliberate move to reduce the burden of inspection on schools and target those that needed help the most.
This contrasts with the approach taken in England where Ofsted aims to inspect all schools, barring those classed as outstanding, every five years. In 2014-15, Ofsted inspected 4,525 state primary and secondary schools and the watchdog currently employs about 160 HMIs.
There are also around 1,600 additional inspectors working for Ofsted and 1,243 have schools as their core remit and are guaranteed at least 16 days inspection per year.
Curriculum for Excellence
Scotland's school inspectorate can call on the support of teaching professionals who have undergone specialist training to carry out inspections.
It has 422 associate inspectors, of whom 96 are trained to inspect primary and secondary schools. Each associate inspector is deployed about twice a year.
Education Scotland said the drop in school inspectors was due to the more supportive role the body had taken on during the implementation of the new curriculum. It planned to increase inspections in future years and was in the process of appointing a number of new HM Inspectors, a spokesperson said.
“As we move into the next phase of Curriculum of Excellence, it is timely that we shift the balance from intensive support for implementation, to a stronger emphasis on evaluating what is working best and sharing those practices more effectively," she said.
"This will require us to once again increase the number of school inspections in the forthcoming years. It is of the utmost importance that Education Scotland utilises its independent role and continues to respond to changes in the education system by offering the most appropriate blend of support or challenge to teachers, schools and the education system.”