We all know the feeling. You take your annual leave and go on a terrific holiday. Perhaps some cultural time in the capitals of Europe. Perhaps a noodle and beer-intensive tour of South East Asia.
Then you return to work. The swivel chair sits forlornly awaiting your return. Hundreds or thousands of emails demand your attention.
You dive into work with a mixture of novelty and regret – this used to be very familiar, you think, and now it is not. At least until around midday, when it will seem as though your holiday never happened at all.
But it turns out there is clear evidence of the holiday. It can be measured in your performance. A recent working paper released by the US National Bureau of Economic Research finds that rather than refreshing your batteries, the holiday makes your performance worse.
And here’s the really bad news:
The study was done on surgeons.
Fatality risk increased for every day the surgeons took off between procedures.
In the study the mean mortality rate the first day after surgery was 0.62 per cent. Mortality rose by .05 percentage points for every extra day it had been since the surgeon held a scalpel. That is a 7.4 per cent rise in the risk of dying.
The study (Hockenberry and Helmchen) covered 56,000 patients and 188 surgeons and focused on a procedure called coronary artery bypass grafts.
Hospitals prefer doctors who do a lot of surgeries, because they are more effective. Surgeons who did more than 100 of the procedure per year had lower one-day mortality outcomes (0.52 per cent), but for them, time off was even worse. For every day of rest, the morbidity rate of their next surgery rose by .09 percentage points.
The doctors did not perform worse on absolutely every measure. When they were back from a break, they apparently sped through the surgery, using less resources. Each day off correlated with a fall in the cost of surgery of 0.6 per cent.
But the saving was well below the value of life lost. In other words, society would prefer the doctors to spend more time and money. The researchers theorise that the cost effect and the morbidity effect are related – relaxed surgeons with their brain still on the golf course are failing to notice important complications and therefore closing up when they should be doing more work.
“After temporal breaks, surgeons may fail to identify and treat life-threatening complications.”
The effect was stronger for surgeons if they had had a lot of time off from surgery in general, rather than if it had been a long time since they undertook the specific procedure being studied.
The effect requires more study before we can determine a policy response.
If the depreciation of skill happens exponentially the longer doctors are on break, we could encourage them to take several two-to-three day breaks a year, rather than one four-week holiday.
But if the depreciation of skill has a linear or decreasing relation to time away, doctors could be encouraged to take all their leave in a lump. General learning theory suggests most forgetting happens straight away, suggesting the latter solution would be preferred, but this study did not attempt to answer the question.
The research is part of a field of study that looks at human capital and how it erodes. It is well-established that the amount of time that elapses between repetitions of a task decreases the quality of outcomes.
This raises questions about a lot of training courses the modern office worker is encouraged to attend. Is the day off worth the meagre benefit if it also makes the worker less productive on their return?
The link between time off and productivity may also have negative implications for going part-time, buying extra leave, and taking career breaks. These issues are ever more relevant in the modern economy where parental leave is all the more common, where people change jobs often, and where jobs may encompass a wide range of tasks undertaken infrequently, rather than repetition of a few tasks.
There is room for a lot more research on this question, but for now, there is one clear lesson: Don’t choose a surgeon with a suntan.