Workplace absence cost the UK economy £12.2bn in 2004 - with concern that £1.7bn of that cost is due to staff "pulling sickies" rather than absence resulting from genuine ill-health.
The latest annual CBI-AXA Absence Survey of over 500 organisations alo shows that 6.8 working days were lost per employee in 2004, costing £495 per employee in 2004 compared with £475 per employee in last year's survey.
The overall cost of £12.2bn has increased from £11.6bn in the previous survey, with rising labour costs and growth in average earnings pushing up the total cost despite the lower absence level.
But as revealed earlier this week, public sector absence outstripped private sector absence by almost three days per employee in 2004, averaging 9.1 days per public sector employee and costing the UK economy £4.1bn.
Though the public sector represents only 30 per cent of the UK workforce, it accounts for 40 per cent of the total number of working days lost to absence.
The total number of days lost to absence across the UK economy fell by 4.5 per cent to 168 million in 2004, from 176 million in 2003, bringing total absence back in line with the level seen in 2002 (166 million days).
The survey also reveals that organisations fear as many as 23 million - or 14 per cent - of the 168 million working days lost to absence last year were a result of unwarranted absence, or staff "pulling sickies". This represents a cost of £1.7bn, broadly the same figure recorded in the previous survey.
Three-quarters of respondents suspect that some employees take illegitimate long weekends by calling in sick on Fridays or Mondays, with three-quarters of organisations saying there was a link between patterns of absence and the unauthorised extension of the weekend.
Two-thirds said they saw an increase in absence around Bank Holidays.
Genuine minor illness - such as flu - was the main cause of absence across the economy in 2004. The second most significant cause of absence was stress among non-manual workers, and recurring illness (for example back pain) among manual workers.
John Cridland, CBI Deputy Director-General, said: "Employers understand that staff are not invincible. They accept that the majority of absence is due to genuine minor illness and nobody is saying genuinely ill staff should drag themselves to work.
"But let's be honest about this - there are some employees out there who will gladly award themselves a day off when they are in good health at the expense of their employers and hard working colleagues.
"With summer almost upon us, employers may well be concerned about staff granting themselves days off that they are not entitled to."
The survey, which has been conducted every year since 1987, also shows manufacturing firms reported higher absence levels than service sector companies in 2004 - 7 days lost per employee compared with 6 days lost.
Manual workers have significantly higher absence rates than non-manual employees. The average for manual workers was 8.4 per employee in 2004, compared with six days per employee for non-manual staff.
Larger organisations also reported higher absence levels than smaller ones. Those employing over 5,000 staff averaged 8.3 days per employee, while companies with less than 50 employees averaged 4.5 days.
The lower absence rates for smaller firms may be because absence it is dealt with by senior management, the CBI said. When senior managers are put in charge of absence, 2.3 fewer days are lost per employee compared with absence dealt with by line managers.
Eighty-seven per cent of organisations are taking action to reduce absence and return-to-work interviews are the most common absence management policy. Two-thirds of respondents have a stress management policy and 60 per cent have rehabilitation schemes in place.
"Companies and organisations are increasingly employing new and innovative methods to manage absence and to help people get back to work quickly," John Cridland said.
"But business also needs efficient health services so staff can make swift recoveries. Employers will be looking to the newly elected government to deliver on its promises for NHS reform."