Stress-related absence levels have increased in the past year and are the main cause of long-term absenteeism in the public sector, according to new research.

Workers in the public sector took an average of 9.6 days off sick a year, three more than employees in private firms, said the Chartered Institute of Personnel and Development (CIPD).

The cost of public sector absence was almost £900 per worker every year, £300 more than the average across British industry, the study of over 500 employers found.

More than one in three employers said stress-related absence had increased over the past year.

Dr Jill Miller, a CIPD adviser, said: “The survey shows why closing the gap between public and private sector absence has proved so difficult for successive governments.

“Compared with the private sector, more public sector employees are in challenging public facing roles such as social work, policing, teaching and nursing where they often have to deal with people in difficult and emotionally charged situations, putting pressure on their time and resilience.

“In addition, organisational change and restructuring is cited more commonly by public sector employers than those in other sectors as a major cause of stress, which will only increase in the near future as a consequence of the recent comprehensive spending review.”

The CIPD said the study showed that the recession and the subsequent recovery had taken its toll on absence.

Over a third of employers reported an increase in mental health problems such as anxiety and depression, a big rise on last year’s survey when one-fifth reported an increase.

Only one in five of organisations said they had increased their focus on employee well-being and health promotion as a result of the recession.