Outsourcing National Health Service Surgery to the Private Sector: Waiting Time Inequality and the Making of a Two-Tier System for Hip and Knee Replacement in England.

This study analyzes National Health Service (NHS)-funded elective primary hip and knee replacement admissions and waiting times in England by provider (the NHS and private), socioeconomic deprivation and comorbidity, both prior to the introduction of Independent Sector Treatment Centers from 1997 to 2003 and following the rapid expansion in NHS contracts with the private sector from 2008 to 2019. Between 1997 and 2019, NHS-funded admission rates more than doubled. Between 2003 and 2008, when the proportion of patients treated in the private sector was negligible, admissions to the NHS increased and waiting times more than halved. After 2008, following the expansion in use of private providers by the NHS, NHS admission rates fell and waiting times rose for all patients. Waiting times for private providers were half those for the NHS, and the poorest 20 percent waited longer than the richest 20 percent. Between 2003 and 2019, inequalities in waiting time rose for the poorest 20 percent. The introduction of private providers into the NHS is associated with a contraction in in-house NHS provision, increasing waiting times for all patients and a two-tier system operating in favor of the rich.