Incremental cost:utility ratio (quality-adjusted life years (QALYs))

A cost–utility analysis using the EQ-5D-3L responses will be performed to generate QALYs, which will generate an incremental cost per QALY. An economic evaluation will be undertaken to explore and determine the incremental costs and benefits of the IMT added to PR programme over a 6-month time horizon. This follow-up period aims to capture the direct effects of the interventions and offer insights into outcomes and costs accrued in the months after the intervention is completed. Direct medical and overhead costs and indirect patient costs will be estimated. Direct costs were estimated using time-and-motion analysis, and included procedure personnel and supplies.

An incremental analysis will be undertaken to calculate the difference in costs and the difference in outcomes (improvements in effectiveness measures and QALYs) associated with the IMT and PR programmes. QALYs will be calculated as the area under the curve connecting the utility scores reported at baseline and the subsequent follow-up points.17 The results will be presented in the form of incremental cost-effectiveness ratios, reflecting the extra cost for an additional unit of outcome. A sensitivity analysis will be performed to assess the robustness of the results to different values.