A methodological framework to guide the development and use of economic evaluations of oncology treatments in informing decision-making

Abstract: Economic evaluations of cancer typically share the same structure articulated around three health states: (i) pre-progression,(ii) progressed disease and; (iii) death. The time spent in the first two health states is typically estimated using progression-free survival (PFS) and overall survival (OS) Kaplan-Meier (KM) curves reported in clinical trials which are then weighted according to the quality of life associated with each state to estimate overall health gains (quality of life years - QALYs). There is increasing evidence that different analytic approaches may provide different estimates and therefore lead to different estimates of total health gains and costs. Identifying when particular approaches may perform better than others subject to the nature of the data available is required. The aim of this research is to develop a methodological framework to guide the development and use of economic evaluations of oncology treatments in informing decision-making. In particular this research will attempt to address the following question: Is it possible to identify when particular analytical approaches may perform better than others subject to the nature of the data available? This research involves a systematic review to identify approaches that are currently used in cancer models to estimate health state durations and total QALYs gained. This will be followed by a review of methods that are used outside economic evaluations to model the dependence PFS and OS. Following identification, the performance each method will be assessed in a simulation study and findings validated in case-studies using real clinical trial data. As a result of this process, a draft methodological framework will be produced describing the advantages and limitations as well as circumstances when particular approaches may perform better than others subject to the nature of the data available. Barriers and facilitators to the implementation of the framework will be evaluated by decision-makers and analysts from the health economics community. The draft framework will be refined prior to wider dissemination.