Amanda Spielman, Ofsted’s new chief inspector, says it is a myth that children in England are overtested, pointing to international comparative studies from Cambridge Assessment.

The same claim has been made by the Organisation for Economic Cooperation and Development’s (OECD) Andreas Schleicher with reference to testing in the US.

In using the word “myth”, both seek to rebut a “widely held but false idea”.

However, the idea that we overtest our students cannot be rebutted simply by appeal to other children in other places, if they are being over-tested as well.

It may be that our students are no more tested than those in, say, the United States. But what help is that when the debate about testing is, if anything, even more heated there than in England?

Diane Ravitch has called standardised testing “the monster that ate American education”, and urges parents and states to boycott them.

Pasi Sahlberg is quite clear on the narrowing effects of standardised testing in the US. ED Hirsch - not exactly a cheerleader for progressive education - has shown how “invalid” tests have bent teaching and learning out of shape.

A better definition of “myth” is the more technical anthropological one of a “a traditional story, concerning the history of a people or explaining a natural or social phenomenon, and typically involving supernatural beings or events.”

Through this prism, the quantitative amount of testing is not the point; the point is the effect of the testing on education, which depends on context and on how the tests are perceived.

In England, the prevalence of high-stakes testing linked to school status, teacher accountability and student progression, creates considerable backwash, disfiguring both curriculum and pedagogy.

The impact on curriculum is well-attested. Time allocated to subjects covered in high-stakes tests expands and squeezes out other curriculum subjects, impoverishing the educational experience.

This is true of standardised testing here and in the US, and it’s true too of the way that GCSEs were bundled up into the EBacc. The impact on teaching is no less consequential, with test-prep taking precedence over teaching for real understanding and engagement.

Assessment plays a crucial role in education. Setting and monitoring suitably challenging targets for students depends on it.

But testing as an end in itself has elevated assessment above mere curriculum and pedagogy. As Thomas Huxley pointed out at the birth of high-stakes testing, “examinations, like fire, make good servants, but poor masters”.

The verb “to assess” derives from the Latin assidere, “to sit beside”.

Originally referring to tax collection, it reminds us nevertheless that in educational terms, assessment (and by extension, testing) should be something we do with and for pupils, and not to them; still less should we be doing it to schools and to teachers.

Asserting that students do not take too many tests misses the point. It is not the substance of the tests that matters, it is the shadow they cast.

As Huxley is also reputed to have said, “Students learn to pass, not to know. They do pass, and they don’t know”.

Dr Kevin Stannard is the director of innovation and learning at the Girls’ Day School Trust. He tweets as @KevinStannard1

For more columns by Kevin, visit his back catalogue

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