Offshore outsourcing is starting to hit IT workers in the pocket, as premiums paid for some skills and certifications begin to "collapse".

A review of nearly 40,000 IT workers by researchers Foote Partners found that the level of bonuses paid for particular skills or qualifications is dropping.

In 2003, the overall premium an IT worker could expect to receive for having certain technical skills was 23 per cent lower than in 2001.

Similarly, the value of being certified in a particular skill was 11 per cent lower than in 2001.

David Foote, president and chief research officer at Foote Partners, said: "The interest in hiring talent abroad at cheaper rates has put downward pressure on skills and certificates pay this year.

"As more work is transferred offshore, premium pay becomes unnecessary. It is one of the reasons why IT certifications pay specifically began collapsing in 2003."

But it is not all bad news, as some qualifications still seduce employers. Candidates with credentials in project management, security and Linux remain sought-after and continue to attract increasing bonuses.

The premium paid for a Red Hat Certified Engineer rose by 13 per cent in 2003, according to Foote Partners.

Other areas have faired less well. Internet qualifications, like Microsoft Certified Professional + Internet, attracted premiums almost a third lower than two years ago.

A Siebel Certified Consultant qualification also saw a marked decrease.

But the overall trend is that firms are happier rewarding certified staff than untested experience.

"Many managers see certification as a more meaningful measure for comparing IT workers," said Foote.

Those with skills and experience, but not formal qualifications, in .Net, DB2, Baan and Novel Groupwise have all seen a drop in demand in 2003.

According to the research, Linux skills gained the most value overall. IBM WebSphere also attracted higher bonuses.