It’s election time: think of a number, a big number

Knife crime, and its effects on the NHS, has become a big talking point in the elections in Scotland.
Labour has promised a mandatory prison sentence for anyone found in possession of a knife outside their home. It promises to set aside £20 million to provide the extra prison places that will be needed if more people are sent to jail – as seems inevitable, as at present not all those found about with a knife are imprisoned.
To back up the policy. Labour’s leader in Scotland, Iain Grey, and Labour Finance spokesman and former Health Minister Andy Kerr, have asserted that knife injuries cost the NHS in Scotland £500 million a year. As the total NHS budget north of the border is £11 billion a year, if this claim is true knife injuries would account for 4.5 per cent of it.
Knife injuries, classified as “assault by sharp object”, are counted by NHS Scotland. The graphs below show recent trends both in deaths and emergency hospital admissions caused by assault by sharp object. The data, taken from here, say that there were 45 deaths and 1,245 admissions in 2009, accounting for approximately 2 per cent of all hospital admissions due to unintentional injury. (unintentional in this context is as seen by the victim, not the perpetrator.)
Somewhat suprisingly, a different figure was quoted by Nicola Sturgeon, the Scottish Secretary for Health and Wellbeing, and Deputy First Minister, in a parliamentary answer in March. She said that there had been 1,606 such admissions in 2009, 1,309 of them on an emergency basis and the other 297 on an elective basis Neither of these figures agrees with the offical statistics, which is puzzling. She said no data was yet available for 2010.
There were 514,217 emergency admissions in total in Scotland in 2009-10, so “sharp object” victims – often the victims of knives but sometimes of bottles – represent a very small fraction of the total. Ms Sturgeon, in answer to another question, said that 3,414 bed days had been occupied in 2009 for those suffering from assault by a sharp object.
A day’s stay costs about £500 (derived from the Scottish Executive’s NHS costs website) so 3,414 bed days would cost £1.7 million.
Not all knife victims are admitted, of course, with many being treated in A&E. But how many? There may be statistics on this but if there are they have eluded me. But the Scottish Crime and Justice Survey for 2009-10 found 945,419 crimes of which 2 per cent were serious assaults. Any crime involving a knife would be classified as a serious assault. This gives a figure of around 19,000 serious assaults, and a report on knife crime for the Scottish Parliament estimated that of violent crimes where a weapon was used, 42 per cent were knives. That suggests a figure of around 8,000 assaults involving knives. Not all resulted in injury, but let’s assume for the sake of argument they all did.
If 1,606 victims were admitted to hospital, the rest must have been treated elsewhere or required no treatment. Let’s assume all 6,400 went to A&E, where the average cost of treatment is £100. That produces a total of £640,000.
Together with the inpatient costs calculated earlier, that amounts to £2.3 million a year. There are ambulance costs to be added, some out-patient follow-ups, occasional plastic surgery. There are a lot of assumptions in my analysis, but with the best will in the world and even if we assume that treating knife injuries is more expensive than the average inpatient cost, it’s hard to see the total exceeding £10 million a year – or 50 times less than the Scottish Labour Party is claiming.
There is another way of looking at it. Studies have been carried out in England & Wales that provide a better estimate than mine of what the true costs might be. One such study by the Trauma Audit Research Network at the University of Manchester, published in Injury in 2008, estimated the cost of kife injuries to the NHS in England & Wales as £7,699 per case. It looked at all the costs involved, including ambulances, surgery and hospital stays.
Applied to Scotland’s 1,245 cases per year, that would amount to just under £10 million. If Ms Sturgeon’s figure is right, it would be slightly higher.
Whichever calculation you prefer, it’s evident that the Scottish Labour Party figure is a fantasy.