By Sean Coughlan

Sleep deprivation is a significant hidden factor in lowering the achievement of school pupils, according to researchers carrying out international education tests.

It is a particular problem in more affluent countries, with sleep experts linking it to the use of mobile phones and computers in bedrooms late at night.

Sleep deprivation is such a serious disruption that lessons have to be pitched at a lower level to accommodate sleep-starved learners, the study found.

The international comparison, carried out by Boston College, found the United States to have the highest number of sleep-deprived students, with 73% of 9 and 10-year-olds and 80% of 13 and 14-year-olds identified by their teachers as being adversely affected.

In literacy tests there were 76% of 9 and 10-year-olds lacking sleep.

This was much higher than the international average of 47% of primary pupils needing more sleep and 57% among the secondary age group.

Achievement gap

Other countries with the most sleep-deprived youngsters were New Zealand, Saudi Arabia, Australia, England, Ireland and France. High-performing Finland is also among the most lacking in sleep.

Countries with the best records for getting enough sleep include Azerbaijan, Kazakhstan, Portugal, the Czech Republic, Japan and Malta.

The analysis was part of the huge data-gathering process for global education rankings – the Trends in International Mathematics and Science Study (TIMSS) and Progress in International Reading Literacy Study (PIRLS).

I think we underestimate the impact of sleep… on average, children who have more sleep achieve higher in maths, science and reading”

These are among the biggest international benchmarks for education standards, based on tests taken by more than 900,000 pupils in primary and secondary schools in more than 50 countries and regional administrations.

The rankings of results for maths, science and reading were published at the end of last year, with Asian education systems dominating the top of the tables.

But the researchers also wanted to find out more about the influence of home life. There has been much analysis of the impact of family wealth and poverty, but the Boston College researchers also wanted to measure factors such as sleep and nutrition.

So the tests were accompanied by questionnaires for teachers, pupils and parents about sleep patterns. And this information was compared with pupils’ test results, so that the performance in maths, science and literacy could be compared with levels of sleep.

Brain food

“I think we underestimate the impact of sleep. Our data show that across countries internationally, on average, children who have more sleep achieve higher in maths, science and reading. That is exactly what our data show,” says Chad Minnich, of the TIMSS and PIRLS International Study Center.

Read More BBC News – Lack of sleep blights pupils’ education.