For about a year, nurses at the Svartedalens retirement homehave worked six-hour days on an eight-hour salary.They're part of an experiment funded by the Swedish governmentto see if a shorter workday can increase productivity. Theconclusion? It does.

As with any cultural shift in the workplace, the six-hourday has to prove itself more than just humane. For anyemployer, in Sweden or elsewhere (and perhaps especially in theU.S.), an abridged workweek can't damage productivity if it'sgoing to have a chance.

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A year's worth of data from the project, which compares staff atSvartedalens with a control group at a similar facility,showed that 68 nurses who worked six hour days took half asmuch sicktime as those in the control group. And they were 2.8times less likely to take any time off in a two-week period,said Bengt Lorentzon, a researcher on the project.

"If the nurses are at work more time and are more healthy, thismeans that the continuity at the residence has increased,"Lorentzon said. "That means higher quality [care]." Less surprisingwas that the nurses were 20 percent happier and hadmore energy at work and in their spare time. This allowed themto do 64 percent more activities with elderly residents, one of themetrics researchers used to measure productivity.

Svartedalens is part of a small but growing movement in Europe.Sweden has dabbled with shorter workdays before: From 1989 to2005, home-care-services workers in one Swedishmunicipality had a six-hour work day, but it was abolished dueto a lack of data proving its worth. The Svartedalensexperiment is designed to avoid that problem: "This trial is very,very clean because it's just one homogenous group of workers," saidLorentzon. In Sweden's private sector, the practice is takingroot in places such as Toyota service centersin Gothenburg.

In the U.K., a marketing agency adopted a staggered schedule to allow forreduced work hours while ensuring coverage;a survey last month found that six out of 10bosses in that country agreed that cutting hours would improveproductivity.

The key result of the Swedish study—that productivity canincrease with fewer hours worked—eliminates a major stumblingblock to globalizing the shorter work day. "The six-hour workweek has not been well accepted in many countries becauseorganizations are worried their productivity mightfall," said Pramila Rao, an associate professor of humanresource management at Marymount University.

Even with encouraging results, it's unlikely that the U.S. willsoon shift to shorter days. Americans work around 38.6 hours perweek, according to the Organization for EconomicCooperation and Development. They get, onaverage, fewer than eight paid vacation days a year; onlyabout three-quarters of workers get any paid time off at all,according to the U.S. Bureau of Labor and Statistics. "TheSwedish model will not be easily accepted in the U.S. because weare a nation of workaholics," said Rao.

"In many companies today, you still see that mentality that youhave to be in the office," added Carol Sladek, work-life consultinglead at Aon Hewitt LLC. "Reducing the workday is very foreignto our overall values."

John Maynard Keynes didn't think so. He famously predicted thattechnological progress would lead us to shorter weeks and abundantleisure time; a 15 hour workweek should be the normby 2030, he prognosticated. The prophecy was echoed byHerman Kahn, who in the 1960s said Americans would one day have 13weeks of vacation and a four-day work week. That's definitely notthe reality in 2016 America.

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The Swedish study isn't the first that made a connectionbetween happier, rested workers and better outcomes for employers.Any link between hours worked and productivity was shown tobe weak in a 2014 paper from Stanford University. Theresearch found a "non-linear" relationship between hours worked andoutput: Results start to slide around the 50-hour-per-week mark. Infact, too much work can damage productivity. People who feeloverworked said they make more mistakes at work,according to a study by the Families andWork Institute.

While the Svartedalens experiment offers evidencethat shorter hours improve productivity, nursing asan occupation may be more analogous to that of medical residents, rather than a desk job. Thestudy equates productivity with quality of care, whichdoesn't necessarily translate to white-collar work.

Then there's the math problem. Cutting worker hours can costemployers money if increased productivity saves less than thecost of hiring additional workers. Svartedalens had to hire anadditional 15 nurses, which cost 6,000,000 Swedish krona(about $735,000). About half of that expense was offset by thedecrease in sick days and time off. That said, the experimentdidn't measure how the improved care affected the overall bottomline.

In the U.S., companies have sought to show flexibilityby adopting a four-day workweek, albeit withthe same total amount of hours. In a sort of workplacesleight-of-hand, the prospect of perpetual long weekends keepspeople motivated. "It helps them stay more focused," said Rao.

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About 30 percent of 1,060 employers surveyed by Aon Hewitt offera compressed workweek. Almost 60 percent of organizations that weresurveyed offer flextime, which allows people to decide what timethey arrive and leave. Research has found that workers who have control overtheir schedules report lower levels of stress, burnout,and higher job satisfaction.

"Employees would rather have more time off, but absent that,giving a little control is a good substitute," saidSladek. "We're like toddlers: As long as we have control overour environment, we feel good."

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