This year's survey is the first since the launch of the fit note - the new medical certificate focussed on what people can do rather than what they can't, designed to aid returns to work and reduce absence costs.
Despite the introduction of the 'fit note' in April 2010, the rate of absence last year was higher than in 2009, when employees averaged 6.4 sick days, the lowest rate since the survey began in 1987.
The 190 million days cost employers £17 billion, including over £2.7 billion from 30.4 million days of non-genuine sickness absence. This does not include the other indirect costs of absence, like lower customer service and lost productivity.
Despite strong support for the initiative, employers have been disappointed by their experience so far. Two thirds (66%) of firms said that it had not yet helped their rehabilitation policy, and 71% were not confident that GPs were using the fit note differently from the old sick note.
Employees in the public sector took more sick days than those in the private sector, an average of 8.1 days a year compared with 5.9 days. This represents an improvement on last year's average of 8.3 days and a marked improvement since 2007's average of 9 days.
Far more absence in the public sector is long-term than in the private sector, and reducing this will be key to reaching private sector levels. The CBI estimates that if the public sector could reach private sector absence levels, it would save the taxpayer around £5 billion by 2015-16.
The cost of absence is much higher in the public sector - a median of £1,040 compared with £710 in the private sector, or a difference of 46%.
Katja Hall, CBI chief policy director, said: "There's been no let up in the cost of absence to the UK economy, which runs into billions of pounds a year. Although many organisations have been successful in bringing down levels of absence, the gap between the best and worst has widened.
"The substantial costs of absence to the economy put a premium on managing longer-term absence well. The fit note is a great initiative, which could play an important role in helping people back to work and stopping them slide into long-term absence. But employers are far from convinced that the scheme is working properly and don't think GPs are getting the necessary training.
"The launch of the electronic fit note should be an ideal opportunity for the Department of Work and Pensions to extend the reach of its training programme and address GPs' engagement. There can be no room for complacency in addressing the so-called sick note culture.
"Sadly, more days were lost to non-genuine absence than in 2009 and the cost of these bogus sick days is over £2.7bn a year. Sickies are unfair on colleagues and damage employers' competitiveness at a critical point in the recovery."
Long-term absence accounts for nearly a third (32%) of all time lost to sickness. In the public sector, the proportion is even higher, with long-term health problems causing nearly half (47%) of days lost, whereas in the private sector long-term absence accounts for 27%.
Mental health issues are the single biggest cause of long-term absence, followed by musculoskeletal disorders, back pain and cancer treatment.
Berkeley Phillips, UK Medical Director, Pfizer, said: "Long-term absence is a concern, and costs associated with longer periods of ill-health are especially high in the public sector. Many people with long term health problems want to work and contribute to society, but the longer employees remain off work, the harder reintegration into the workplace becomes. This report highlights the importance of early intervention and proactive management strategies to support employees and employers in tackling the factors contributing to long-term absence and supporting a return to work.
"The economic consequences of long-term absence stretch beyond the individual workplace to deliver a significant impact on society. By drawing together data on both absence trends and management strategies, this report highlights how both employers and policy makers can deliver significant benefits to maximise wellness and minimise illness for the UK workforce."
