Migrants are better qualified and holding down better-paid jobs than people born in the UK, according to a major international study published yesterday.

Figures show that 34 per cent of migrants in the UK have a post-school qualification; 4.9 percentage points higher than the figure for non-immigrants. They are also better paid than migrants in most other countries and UK-born workers, putting less of a strain on the benefit system, according to research by the Organisation for Economic Co-operation and Development.

A quarter of international students from outside Europe complete their studies in the UK and stay on in the country, said Andreas Schleicher, head of the indicators and analysis division at the OECD and author of the report. "The benefits to your economy from them are great," he said.

His intervention comes at a time when universities fear that visa restrictions will drive international students away from UK universities. Baroness Blackstone, vice-chancellor of Greenwich University and a former Labour Universities minister, said applications to her university were 10 per cent down this year.

"Migrants tend to be better qualified with a higher proportion of degree holders," Mr Schleicher added. "It is a very interesting factor that often gets lost in the public debate about immigration."

Yesterday's report also revealed that poorly qualified UK adults had been some of the hardest hit by the recession in the entire world. Figures showed the employment rate amongst 15- to 29-year-olds without at least five A* to C grade GCSE passes had fallen from 65.6 per cent to 56.9 per cent – a slump four times higher than the international average.

"Adults (without the equivalent of five top-grade GCSE passes) have borne the brunt of the economic crisis and seen a marked drop in their employment prospects between 2008 and 2009 [the years of the study's findings]," said the report. It added that this showed "significant vulnerability for individuals with less education".

The survey also showed that the UK trails behind other countries in the percentage of young people going into higher education, despite a massive increase in the past decade. And, of the 30 countries in the survey, 25 had higher rates of 15- to 19-year-olds in education and 27 had a higher rate of 20- to 29-year-olds in education.

"Even before the Government decided to treble tuition fees and slash funding, UK participation in higher and further education was already languishing near the bottom of the table and they have now put us at risk of dropping even further still," said Liam Burns, president of the National Union of Students.

The report also showed that a major investment in education in the UK between 2000 and 2008 had seen a significant drop in class sizes – particularly in secondary schools where the average had dropped to 19.6 pupils, well below the OECD average of 24.

Case study

Sujatha Santhanakrishnan, 27, from London

"I'm from Madras, in India. I came to work for an investment bank in the UK in 2007. The pay was good, but I didn't find the work rewarding, so I left to do a Masters in comparative politics at the London School of Economics.