The wisdoms of other disciplines

It seems common sense that you need a bit of spare capacity (in hospital beds, as in many other things) to cope with emergencies. Yet common sense doesn't always turn out to be correct, so it's good to have it confirmed by some rather more robust methodology—as it is in this week's BMJ by an elegant bit of discrete-event stochastic modelling. High bed occupancies are seen as desirable by health purchasers because they suggest efficiency. However, when Adrian Bagust and colleagues modelled the dynamics of a hospital system they found that the risk …