On Friday 11 January 2018, the RSS Northern Ireland local group held a meeting at Queen’s University Belfast. Dr Felicity Lamrock of the National Centre for Pharmacoeconomics (NCPE) spoke on the topic of 'Statistics to consider when appraising cost-effectiveness models'.
Felicity began her talk by describing the NCPE which assesses the cost-effectiveness of new drugs, for which reimbursement by the healthcare payer, the Health Service Executive (HSE), is sought in Ireland. All new drugs seeking reimbursement in Ireland are subjected to a preliminary rapid review by the NCPE. Drugs which are high in cost or have a significant budget impact are required to subsequently complete a full Health Technology Assessment (HTA). A full HTA involves a systematic, evidence-based assessment of the comparative effectiveness, cost-effectiveness and potential budget impact of drugs for use by patients in Ireland. The HTAs are critically appraised by the Review Group (RG) at the NCPE, with the RG consisting of clinical, statistical and health economic expertise.
The cost-effectiveness models submitted with a HTA contains several statistical aspects such as survival analysis, health economic modelling, and evidence synthesis. Felicity first spoke about the components of a cost-effectiveness model, including quality adjusted life years (QALYs), discounting, and incremental cost-effectiveness ratios. The 'willingness to pay' threshold in Ireland was described in detail on the cost-effectiveness plane, as well as how the results of a HTA are used by decision makers in Ireland.
Survival analysis within HTAs was described next by Felicity, with pertinent examples which comprised definitions, common issues such as choosing an appropriate survival curve to fit to clinical trial data, as well as some examples.
The final section of the talk comprised of an explanation of uncertainty within cost-effectiveness models. The sources of uncertainty were described first, followed by examples of deterministic sensitivity analysis, probabilistic sensitivity analysis, and cost-effectiveness acceptability curves.
The event concluded with a stimulating discussion of the concepts raised in Felicity’s talk, involving a number of audience members from a variety of backgrounds.