R and Shiny for Cost-Effectiveness Analyses: Why and When? A Hypothetical Case Study.

INTRODUCTION: Health economics models are typically built in Microsoft Excel® owing to its wide familiarity, accessibility and perceived transparency. However, given the increasingly rapid and analytically complex decision-making needs of both the pharmaceutical industry and the field of health economics and outcomes research (HEOR), the demands of cost-effectiveness analyses may be better met by the programming language R. OBJECTIVE: This case study provides an explicit comparison between Excel and R for contemporary cost-effectiveness analysis. METHODS: We constructed duplicate cost-effectiveness models using Excel and R (with a user interface built using the Shiny package) to address a hypothetical case study typical of contemporary health technology assessment. RESULTS: We compared R and Excel versions of the same model design to determine the advantages and limitations of the modelling platforms in terms of (i) analytical capability, (ii) data safety, (iii) building considerations, (iv) usability for technical and non-technical users and (v) model adaptability. CONCLUSIONS: The findings of this explicit comparison are used to produce recommendations for when R might be more suitable than Excel in contemporary cost-effectiveness analyses. We conclude that selection of appropriate modelling software needs to consider case-by-case modelling requirements, particularly (i) intended audience, (ii) complexity of analysis, (iii) nature and frequency of updates and (iv) anticipated model run time.

Cost-effectiveness of ustekinumab in moderate to severe Crohn's disease in Sweden.

BACKGROUND: Human monoclonal antibody ustekinumab is a novel Crohn's disease (CD) treatment blocking pro-inflammatory cytokines interleukin-12 and 23. The study's objective was to assess cost-effectiveness of ustekinumab in moderate to severely active CD in Sweden. METHODS: A cost-effectiveness model with an induction phase decision-tree structure and a maintenance phase Markov cohort structure was constructed. CD was represented by five health-states: remission, mild, moderate-severe, surgery and death. Ustekinumab was compared to adalimumab in patients who had failed conventional care, some of which had tried TNF-alpha-inhibitor(s) without experiencing treatment failure or side effects ("conventional care failure population") and to vedolizumab in patients previously failing TNF-alpha-inhibitor treatment. Discontinuation probabilities, utilities and ustekinumab induction efficacy were sourced from phase-III trials. Maintenance and comparator efficacy came from network-meta and treatment-sequence analyses. Resource use and unit costs were derived from literature and validated by clinical experts. The analysis had a societal perspective, a life-time time-horizon, and 2-year treatment duration. The results robustness was tested in univariate and probabilistic sensitivity analyses. Cost-effectiveness was estimated using quality-adjusted life-years (QALYs). RESULTS: Ustekinumab dominated adalimumab in conventional care failure population (costs: - €6984, QALYs: + 0.232). In TNF-alpha-inhibitor failure population ustekinumab accrued 0.133 more QALYs than vedolizumab, yielding a €30,282 incremental cost-effectiveness ratio. Results were sensitive to decreasing the time horizon and increased treatment duration. At Swedish reference willingness-to-pay of €63,000 (SEK 600,000), ustekinumab had 94% probability of being cost-effective versus adalimumab, and 72% versus vedolizumab. CONCLUSIONS: Results indicate ustekinumab dominates adalimumab in conventional care failure population, and is cost-effective versus vedolizumab in TNF-alpha-inhibitor failure population.