Impact of Digitised Preoperative Assessment on Surgical Cancellation Rates and Causes: A Retrospective Observational Study (Preprint)

BACKGROUND On-the-day cancellations of elective surgery impose a substantial burden on the NHS, costing an estimated £400 million annually and generating significant environmental waste. Approximately 23% of these cancellations are preventable and linked to preoperative process failures. Digitalising Preoperative Assessment (POA) workflows to replace inefficient paper-based systems is recommended by GIRFT guidelines, yet the operational impact of these interventions on cancellation rates remains under-evaluated. OBJECTIVE This study evaluates the impact of implementing a digital POA platform (Pathpoint ePOA) on on-the-day theatre cancellation rates for elective Trauma and Orthopaedics (T&O) procedures at West Hertfordshire Teaching Hospitals NHS Trust (WHTHT). METHODS A retrospective observational study was conducted using data from 03/04/2018 to 28/11/2025. A Student t-test first compared weekly on-the-day cancellation rates between the pre- and post-intervention arms to assess changes in mean performance. To investigate a potential causal relationship, an Interrupted Time Series (ITS) analysis was applied, utilising a regression model to evaluate level and slope changes while excluding volatile COVID-19 pandemic data (23/03/2020–24/02/2022). Benchmarking local procedure volumes and cancellation rates against national metrics provided context within broader clinical trends. The analysis concluded with the recategorisation of 1,299 cancellation cases into a nine-category schema and a chi-square test to determine if the intervention significantly shifted the proportion of POA-related versus non-POA-related cancellations. RESULTS Average weekly on-the-day cancellation rates significantly declined from 9.0% at baseline to 5.2% following the intervention (p