According to a study, bosses think non-genuine sick days account for up to 25 per cent of absenteeism, when they actually account for less than 15 per cent.
The research from Direct Health Solutions - an absence management firm - found sick days cost the economy about 28 billion dollars a year and CEO Paul Dundon said bosses found this easy to blame on workers.
"They're focussed too much on the odd case of a 'sickie' and not on the genuine factors absence," News.com.au quoted Dundon as saying.
The 2012 Absence Management Survey found that businesses believed the most common reason workers took days off was for unexpected illness.
Employees also view paid sick days as an entitlement, which turned out to be the second most common reason cited by business for leave days.
The study also found absenteeism was higher in large organisations with more than 1000 employees.
"It becomes more complex to manage the bigger a business becomes, and it's easier to fly under the radar and when that happens it kind of develops a culture of absenteeism," Dundon said.
Absence levels were also 21 per cent higher in unionised environments, and 20 per cent higher in the public sector.
The telecommunications and utilities industry had the highest number of days lost at 13.1, followed by travel, tourism and hospitality at 13 and outsources service providers at 11.1.
IT workers had the lowest number of sick days at 4.6, followed by retail workers at 6.5 and manufacturing and production and 6.5.
The study also found that half of employers think it is easy for workers to obtain a medical certificate even when they are not sick.