In this issue, Cole and his colleagues elegantly demonstrate the use of modelling to estimate health impacts of a policy.¹ The Los Angeles City living wage ordinance sets a minimum wage for certain city employees. It also requires employers to contribute towards health insurance premiums for the affected workers or to add that payment to their wages. Using results from other studies in a novel way, they found that provision of health insurance is a more cost effective measure to improve health than a modest rise in income in their Los Angeles population.

This is unsurprising in the American context. For the relation of health to the provision of any type of resource, there is likely to be a diminishing return so that the gradient of the relation becomes flatter as the level of the resource increases.² The steepest part of the curve is the increase above zero. The many uninsured in the USA will therefore gain appreciably even from low …