It would be an unusual business that chose to meet its staffing needs by hiring a string of expensive agency temps when it might solve the problem more cheaply by hiring permanent staff, yet the NHS appears to be falling into that trap.

In the year to March, health boards spent £60 million on hiring temporary doctors and nurses, up 25% on the year before, with the cost of agency nurses showing a particularly steep increase of 60%. This is alarming since it raises the possibility that locums are being used, not just to plug unavoidable gaps in staffing caused by staff absences, but as a substitute for full-time staff.

Locum doctors and nurses will always have an important role to play, from GPs brought in to provide holiday cover to nurses boosting staffing levels during unexpectedly busy periods. The concern is, however, that the dramatic increase in the number of medical staff being employed on a short-term basis is masking long-term gaps in the workforce. The high cost of locums in Scotland's three island health boards, Orkney, Shetland and Western Isles, is an indicator of how difficult it can be to attract permanent staff to remote communities. Certain medical specialisms also struggle to fill posts because of perceptions that the job is particularly stressful, emergency medicine for one. More than 50 hospital consultant posts in Scotland have been vacant for at least six months. Could it be that increasing patient demand is also leading to higher demand for staff? The Herald's campaign, NHS: Time for Action, has called for a review of staffing levels to ensure that the right staff are in place to cope with the growing demand from the ageing population. The system of medical training is supposed to ensure the right numbers of doctors and nurses are produced to meet the NHS's needs, but the jobs available to them on qualifying must be appealing enough to attract, and, crucially, retain them.

The Scottish Government is working to reduce reliance on locums, but it will need to assess whether it is doing enough. This level of increase in spending on locums cannot continue.