There is some evidence that the UK 'fit note,' which replaced the 'sick note' in 2010 in the UK, is linked to fewer people taking long term sick leave of 12 or more weeks, reveals research published online in Occupational & Environmental Medicine.
But the proportion of people off sick with depression, anxiety, and stress is on the rise, the analysis suggests.
The 'fit note' differs from its predecessor in that it challenges the idea that a patient/employee has to be fully fit before s/he can resume work, by enabling family doctors (GPs) to include advice to both employee and employer on how an individual may be able to go back to work if given support.
This could include a phased return, amending duties, altering working hours, or making workplace adaptations.
The researchers base their findings on 'fit note' data collected from 68 general practices of varying list size in England, Scotland, and Wales between 2011 and 2013, and a comparison of sick note data collected in 2001-02 from seven of these practices.
The information gathered included date of issue, diagnosis, length of time off work, whether the patient may be fit to do some work, and whether a follow up assessment was needed. It also included gender, birth date, and postcode so as to identify practices located in areas of deprivation, a known risk factor for long term sick leave.
Almost 14,000 periods of sick leave were taken between 2011 and 2013 at the 68 practices. Over half (53%) of all certified periods of sickness absence didn't last beyond 3 weeks; around a third (35%) lasted less than 12 weeks; and the remainder (12%) exceeded 12 weeks.
Certain factors seemed to be more closely linked to longer periods of sick leave. Being male, older, and living in a deprived area were significantly associated with taking time off work lasting more than 3, 6, and 12 weeks.
GP partners were also more likely than salaried or locum GPs to sign patients off sick for periods of 12 or more weeks.
The comparison of sick and fit note data from the seven practices suggests that fewer people are taking 12 or more weeks off work than they did in 2001-02.
But the proportion of time off work for mild to moderate mental health issues (depression, anxiety, and stress) rose from 26% to 38% between 2001-02 and 2011-12, and accounted for almost one in three of the fit notes issued to working patients in all 68 practices in 2011-12..
The other notable change was a reduction in the proportion of sick leave taken for respiratory health problems, which fell from 10% to 6%.
Sick leave is costly for the economy, say the researchers. In 2011, an estimated 131 million working days were lost to sickness absence in the UK, costing £13 billion in state benefits plus £9 billion to employers in sickness benefits.
In a linked editorial, Professor Raymond Agius and Dr Louise Hussey, of the Centre for Occupational and Environmental Health at the University of Manchester, caution that there may have been changes in the size and character of the patient lists at the seven practices over the decade.
This would therefore make it difficult to draw definitive conclusions about whether the fit note has changed the likelihood of patients being deemed fit for work, they suggest.
They add that at the end of last year the government started piloting a Fit for Work Service, ahead of national roll-out. The service enables family doctors and possibly employers to refer individuals for a work focused occupational health assessment, with the aim of identifying the factors that may be preventing someone from returning to work.
But given that the study found that nearly half of patients were off sick for more than three weeks, considerable resources would be required to run the scheme effectively, they warn.
"In conclusion, the 'jury is still out' as regards a corroborated, valid and comprehensive assessment of the effect of the fit-note," they write. "Moreover, a thorough and systematic evaluation of the effects of the Fit for Work Service is much needed, especially considering its potentially very large economic implications as well as effects on wellbeing," they add.