In the three days after publication of his outburst - which gave managers a two-week ultimatum to shape up - stock in the American health care company dropped by 22 per cent over concerns about staff morale. It is now trading at more than a third less than it was before the email was sent. Neal Patterson, head of the Cerner Corporation, based in Kansas City, has spent the past three weeks trying to assuage investors.

His email to managers read: "We are getting less than 40 hours of work from a large number of our EMPLOYEES. The parking lot is sparsely used at 8am; likewise at 5pm. As managers, you either do not know what your EMPLOYEES are doing or you do not CARE. In either case, you have a problem and you will fix it or I will replace you."

His email read: "NEVER in my career have I allowed a team which worked for me to think they had a 40-hour job. I have allowed YOU to create a culture which is permitting this. NO LONGER." He added that "hell will freeze over" before he increased employee benefits. He wanted to see the car park nearly full by 7.30am and half full at weekends. He wrote: "You have two weeks. Tick, tock."

A week later, the email appeared on a Yahoo financial message board and Wall Street analysts began receiving calls from worried shareholders. Stephen Davas of Goldman Sachs said: "It raised two real questions for investors. Has anything changed at Cerner to cause such a seemingly violent reaction? And is this a chief executive that investors are comfortable with?"

Cerner was included last year in Fortune magazine's list of the 100 best companies to work for in America. Mr Patterson, who founded Cerner in 1979, attributed his blunt management style to growing up on a farm in Oklahoma. He told the New York Times: "You can take the boy off the farm, but you can't take the farm out of the boy."

© Copyright of Telegraph Group Limited 2001

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