The causal effect of hospital volume on health gains from hip replacement surgery

19 August 2019

"The causal effect of hospital volume on health gains from hip replacement surgery" by Laurie Rachet Jacquet, Nils Gutacker and Luigi Siciliani.

This study investigates the causal effect of hospital volume on health gains from hip replacement
surgery in the English National Health Service. We exploit a unique dataset, which links routine
hospital records and patient-reported outcome measures (PROMs) for all public hospitals in England.
PROMs assess patients’ health along key dimensions of pain and mobility shortly before and six
months after the surgery. We investigate whether higher hospital volume increases patient health
six months post-surgery, conditioning on pre-surgery health and other patient medical and
socioeconomic indicators. We address possible reverse-causality bias due to hospital demand being
responsive to quality by constructing a measure of predicted hospital volumes based on a patient
choice model. The results suggest that the observed volume-outcome effect in hip replacement
surgery is clinically small and no longer statistically significant once we account for the endogeneity
of volume.