Do maximum waiting times guarantees change clinical priorities? A Conditional Density Estimation approach

The level and distribution of patient waiting times for elective treatments is a major concern in publicly-funded health care systems. Strict targets, which have specified maximum waiting times, have been introduced in the NHS over the last decade and have been criticized for distorting existing clinical priorities in scheduling hospital treatment. We demonstrate the usefulness of Conditional Density Estimation (CDE) in the evaluation of the reform using data for Scotland for 2002 and 2007. The CDE approach allows for variation in the e.ects of patients’ characteristics over ranges of the distribution and avoids restrictive assumptions about error distribution and functional form. We find that health providers achieved the target by reducing the waiting times for long-waiting patients at the expense of short-waiting patients. We also document a change in the prioritization between di.erent patient groups with some patient groups benefiting at the cost of others.