Employees are being put under increasing strain because their managers are using surveillance equipment to keep track of how hard they are working, according to a survey by the Economic and Social Research Council.

The study found that more than half of employees claim that their managers use electronic systems to keep a log of their work.

It found that in workplaces checked by computer, reports of work-related stress rose by 7.5%. Evidence of added stress was particularly striking among administrative and white-collar staff such as call centres, where it rose by 10% where staff were monitored constantly.

The research found that a fifth of workplaces admit to monitoring their employees using computer-based systems.