A new survey confirms what many employers have long suspected -- most workers who call in sick at the last minute aren't really sick.

Based on interviews with more than 300 human-resources managers at businesses nationwide and across all major industries, only about 34 percent of last-minute employee absences are due to "personal illness." The rest take time off to deal with personal or family issues, according to CCH, a Riverwood, Ill.-based employment services firm.

The real reasons for employee absenteeism range from family issues to personal needs and stress. Indeed, a majority of workers tend to call in "sick" on Mondays or Fridays, with similar patterns appearing around major holidays, the survey found.

Whatever the cause, employee sick days can cost employers more than $760,000 a year in direct payroll losses, on top of lost productivity, revenue, or staff morale, researchers said.

"Unscheduled absenteeism is a problem that no organization can afford to ignore -- either from a cost or productivity standpoint," Pamela Wolf, an employment law analyst at CCH, said in a statement.

Still, Wolf doesn't blame people for taking the odd day off. She said most workers are forced to juggle increasing demands from the workplace, family, or other commitments, creating what she calls a "tug of war" for their time.

"Many employees today are asked to give 110 percent on the job -- to do more with fewer staff, work long hours and handle work-related issues after hours from home," Wolf said. At the same time, these workers are often part of a dual-earning family, single parents, or caregivers for aging parents, she said.

Wolf said employers stand to gain by building a better partnership with employees through work-life balance programs. According to the survey, the five most effective programs for reducing absenteeism were alternative work arrangements, telecommuting, a compressed work week, leave for school functions, and flu-shot programs.

Yet of all these, flu-shot programs were the only ones that were offered by more employers last year, up to 66 percent from 64 percent in 2005.

Wolf called that a signal for employers to "step back and assess if they have the right programs in place for their employees."