Employees took 180 million sick days last year, averaging 6.4 days each, according to the Confederation of British Industry (CBI)/Pfizer Absence and Workplace Health Survey.
The rate of absence is the lowest since the survey began in 1987.
The research, which surveyed senior HR staff from 241 public and private sector organisations, showed the 180 million sick days cost employers about £16.8 billion in 2009, and that 15%, or 27 million sick days, were not genuine.
Public sector employees took more sick days, with an average of 8.3 days per year, which is 43% higher than the private sector figure of 5.8 days. However, the public sector's record has improved since the last CBI absence survey in 2007, when the average was nine days.
Larger organisations had higher rates of absence, and employers have increased their use of structured rehabilitation plans to help people with longer-term illnesses back to work.
Katja Hall, director of employment policy at the CBI, said: "The rate of employee absence has come down, but it still costs the economy billions of pounds a year.
“If absence levels across the board could be reduced by 10%, the economy would see annual savings of just under £1.7 billion. Unfortunately, bogus sick days remain a problem, and are unfair on hard-working colleagues and employers alike."
Long-term absence accounted for 20% of lost days in the private sector and 36% in the public sector. Back pain and mental health issues were listed as key causes of long-term absence.
Dr. Berkeley Phillips, UK medical director at Pfizer, said: “We have long known mental health, back pain and other musculoskeletal disorders are the leading causes of long-term absence, and this year’s CBI report reinforces this.
“While employers view loss of productivity as the main impact of absence, as this report highlights, the economic consequences stretch much further and as such, we as a society, need to do more to advance health and wellness at every stage of life.”
Employers are increasingly using rehabilitation plans and support in which getting staff back to work sooner and productively are major objectives.
The survey showed 95% of organisations had a formal absence policy - a rise of 10 percentage points compared with 2007.
The survey also showed respondents welcomed the introduction of the ‘Fit Note’ in April 2010. Three-quarters (76%) said it would help people get back to work.
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