A worker in a call centre. The calls are timed, the script is fixed, the target went up last month, and nobody can say no to the next call. Nothing is heavy, nothing is loud. Britain's safety body counts what this does to people as an illness caused by work, and it is now the commonest one.
Stress, depression or anxiety964 thousand · 51%
All other work-caused illness936 thousand · 49%
Working people with a work-caused illness, Britain, 2024/25.
Pressure is normal; a job with none is dull. Stress is what happens when the pressure is more than a person can deal with, for long enough to do harm. In 2024/25, about 964,000 British workers had stress, depression or anxiety caused or made worse by work. That is about half of everyone with any work-caused illness.
Stress, depression, anxiety
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Everything else
Of everyone in Britain with an illness their work caused or made worse, about what share is stress, depression or anxiety?
Nearly all of it.
Not yet. About half. The other half is mostly backs, joints and lungs: the slow harms of the earlier lessons.
About one in ten.
Not yet. It is far bigger than that. Stress, depression and anxiety together are the single largest kind of work-caused illness, ahead of bad backs.
About half.
Right. Nine hundred and sixty-four thousand of 1.9 million. It also accounts for about three fifths of the working days lost to work-caused illness, because each case lasts.
How much is asked
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How much say
Two dials. The corner that matters is heavy, and none.
A model from 1979 explains a lot of it with two dials. One is how much the job asks: the pace, the volume, the hours. The other is how much say the worker has: the order, the method, the timing. Heavy demands alone are not the danger. Heavy demands with no say is the corner where the harm gathers.
Set how much the job asks and how much say the worker has. The score is made up and round, shaped on the 1979 model: heavy and no say scores 9, light with a lot of say scores 1.
Strain3 out of 9
The worst corner9 out of 9
Light · LittleLight demands, little say. Not much is asked, and none of it is yours to arrange: dull rather than crushing. Strain score 3 out of 9.
Strain2 out of 9
The worst corner9 out of 9
Light · SomeLight demands, some say. An easy job with a bit of room to arrange it. Strain score 2 out of 9.
Strain1 out of 9
The worst corner9 out of 9
Light · A lotLight demands, a lot of say. Not much asked, and all of it on your own terms. Strain score 1 out of 9.
Strain6 out of 9
The worst corner9 out of 9
Steady · LittleSteady demands, little say. A full day, every step of it decided by someone else. Strain score 6 out of 9.
Strain4 out of 9
The worst corner9 out of 9
Steady · SomeSteady demands, some say. A full day with room to choose the order. Strain score 4 out of 9.
Strain2 out of 9
The worst corner9 out of 9
Steady · A lotSteady demands, a lot of say. A full day you run yourself: the model's good corner. Strain score 2 out of 9.
Strain9 out of 9
The worst corner9 out of 9
Heavy · LittleHeavy demands, little say. More than one person can do, and no way to change the pace, the order or the method. The model's worst corner. Strain score 9 out of 9.
Strain6 out of 9
The worst corner9 out of 9
Heavy · SomeHeavy demands, some say. A lot is asked, and a little of it can be moved around. Strain score 6 out of 9.
Strain3 out of 9
The worst corner9 out of 9
Heavy · A lotHeavy demands, a lot of say. A lot is asked, and how it gets done is yours: hard, but the model expects it to be bearable. Strain score 3 out of 9.
Two jobs both ask a lot. One gives the worker a lot of say, the other none. What does the model expect?
Very different strain: 3 against 9. The same load is bearable when you can arrange it and crushing when you cannot.
Right. The demand dial is the same for both. The say dial moves the score from 3 to 9, which is the model's whole point: control is what turns pressure into strain or into work.
The same strain. Heavy is heavy.
Not yet. Heavy is the same on the first dial. The second dial is where the two jobs part, and on this scale it triples the score.
More strain for the one with a lot of say, because choices are tiring.
Not yet. Choosing is work, but the model and the research behind it run the other way: say is what lets a person pace, order and survive a heavy load.
Move both controls.
How much is asked→How much say→Support→A clear role→How change is handled
Five of the six; the sixth is how people treat each other.
Britain's safety body lists six things it looks at in a workplace. How much is asked. How much say people have. The support they get from managers and colleagues. Whether people treat each other decently. Whether each person knows what their job is. And how change is handled: told, or done to them.
Each card is a change to a job. Which dial does it turn?
One card at a time. Tap the pile it belongs to.
Card 1 of 5
A new target of 60 calls an hour, up from 40.
Shifts now set by an app, with no swaps allowed.
Two colleagues leave and are not replaced.
Scripts that must be read word for word.
The order of the day's jobs is now fixed by head office.
A new target of 60 calls an hour, up from 40. → Asks more
Not yet. Asks more. Half as much again in the same hour; nothing about who decides anything has changed.
Shifts now set by an app, with no swaps allowed. → Less say
Not yet. Less say. The hours may be the same; what has gone is the worker's hand on when they are worked.
Two colleagues leave and are not replaced. → Asks more
Not yet. Asks more. The same work is shared among fewer people, so each is asked more, with the same say as before.
Scripts that must be read word for word. → Less say
Not yet. Less say. The number of calls is unchanged. The method has been taken out of the worker's hands.
The order of the day's jobs is now fixed by head office. → Less say
Not yet. Less say. The jobs are the same jobs; the choice of how to arrange them, which is what the second dial measures, has gone.
Asks morepace, volume, hours
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Less sayorder, method, timing
Right. If the change adds to the pace, the volume or the hours, it turns the first dial. If it takes away a choice about order, method or timing, it turns the second. The worst changes turn both at once.
Surgeonheavy, decides how
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Call handlerheavy, scripted and timed
A surgeon and a call-centre worker both have heavy demands all day. Why does the model expect more strain in the call centre?
The surgeon decides how and when; the call handler reads a script to a timer. The second dial is at opposite ends.
Right. Both jobs score heavy on the first dial. The surgeon's say pulls the strain down; the handler's lack of it pushes the strain up, and the model expects the illness to follow the second dial.
It does not. Heavy demands produce the same strain everywhere.
Not yet. That is the first dial alone. The model's whole claim is that the second dial changes what heavy demands do to a person.
Because surgery is more important, so the surgeon copes.
Not yet. Importance is not one of the dials. Plenty of important jobs with no say are high-strain; the model is about demand and control, not status.
A picker
↓→
Wrist scannerroute set, every pick timed
↓→
Which dial?
A warehouse gives every picker a wrist scanner that sets the route, times each pick, and shows the seconds left. Which dial has it turned?
Only the first. It asks for more picks.
Not yet. It does ask for more. It also decides the route and the order, which were the picker's to arrange, and that is the second dial turning down.
Neither. It is a tool, like a better trolley.
Not yet. A better trolley lowers the demand and leaves the say alone. This device raises the demand and removes the say, which is the opposite on both dials.
Both. The timer raises what is asked, and the fixed route takes away the say.
Right. The seconds on the wrist are a demand that never lets up, and the route decided by the scanner is a choice the picker used to make. That is the model's worst corner, delivered by a device.
Lesson complete
Strain comes from how much a job asks against how much say the worker has; heavy with none is worst.