In this paper the differences in average waiting times are utilized to identify the determinants of demand for health services. The equilibrium waiting time framework is used, but the full equilibrium assumption is relaxed by selecting areas with low waiting times and by estimating a (semi-)parametric selection model. Determinants of supply are used as instruments for the endogeneity of waiting times. A model for the demand for acute services at the ward level in the UK is estimated. The model estimates, and their implications for health service allocations in the UK, are contrasted against more standard allocation models. The present results show that it is critically important to account for rationing by waiting times when identifying needs from care utilization data.
Copyright 2000 John Wiley & Sons, Ltd.