Relations between line managers and employees can be stressful
Firms will have a happier and healthier workforce if employees can tell their managers what they think of them, says a study of workplace behaviour.
The research showed that bosses were more likely to change their management style, and become more effective.
"Without holding a mirror up to a person, they can have blind spots about how they come across," said researcher Emma Donaldson-Feidler.
"If they think they are already good enough, why should they change."
Her research explored the relationships between line managers and employees, which have been found to be the most commonly reported cause of stress in the workplace.
Managers who received feedback from their staff became more effective across a range of measures, including coping with their emotions, empathising with individuals and resolving conflict.
By contrast, bosses who did not receive feedback from staff were less likely to change their behaviour.
"The consequences of stress are pervasive," said Ms Donaldson-Fielder. "Those under stress may experience psychological symptoms, such as anxiety or depression, and physiological symptoms, such as palpitations or raised blood pressure."
She said stress was also a significant cause of sickness absence, which puts pressure on those still at work.
Ms Donaldson-Feidler and her colleagues are now working on a questionnaire that staff can use to rate the quality of their line managers, as well as learning material for bosses.
The study was co-funded by the Health and Safety Executive, the Chartered Institute of Personnel and Development and Investors in People, and is being presented to an occupational psychology conference in Brighton on Wednesday.