A general modelling framework to estimate the impact of waiting times on health for patients undergoing elective procedures in the NHS in England

The NHS currently uses a universal waiting time target of 18 weeks from referral to treatment across a range of elective procedures. If there is variation in the relationship between waiting time and the health benefits obtained across elective procedures or patient groups, there may be scope to improve population health benefits by varying the target. Determining the potential for such an approach requires an understanding of the health consequences of waiting.

We start by outlining a logic model to illustrate the pathway from an individual developing a condition through to the end of their healthcare interactions for the condition. We review previous approaches estimating a relationship between waiting and health and map these onto the logic model. We then propose a general modelling framework to estimate the impact of waiting times on health, measured in quality-adjusted life-years (QALYs), for patients undergoing different elective procedures, conditional on their clinical and socioeconomic characteristics.

We outline the evidence and steps required to apply the framework. These include estimating whether those waiting experience excess mortality risk, whether their health condition is progressive, and health related quality of life deteriorates while waiting, and the likelihood and consequences of exiting the list without receiving the procedure.

The framework can be used to consider the impacts of waiting times targets for elective procedures on population health. Further, our framework, in combination with estimates of the current backlog resulting from the COVID-19 pandemic, can quantify the health consequences of the impact of the pandemic on waiting times.