OBJECTIVES : To improve the accessibility, transparency, and reproducibility of state-of-the-art cost-effectiveness analysis (CEA) methods for users and developers of decision-analytic models.

METHODS : We developed the R package ‘dampack’ (Decision-Analytic Modeling Package) to analyze and visualize CEA results with expanded functionality over similar existing packages. Using standard CEA outputs exported from a model developed in any software, ‘dampack’ facilitates both basic and advanced calculations of CEA results crucial for informing decision making. Users can input results into ‘dampack’ in one of two ways: as a probabilistic sensitivity analysis (PSA) dataset or as deterministic results (e.g., expected costs and effectiveness of each strategy). The package can be used to identify dominated strategies, calculate incremental cost-effectiveness ratios, plot the efficient frontier, and visualize one- and two-way sensitivity analyses. Additionally, for PSA datasets, ‘dampack’ users can construct cost-effectiveness acceptability and expected loss curves and compute the expected value of perfect, partial, and sample information. Sensitivity and value of information analysis functionality are implemented using linear meta-models based on the PSA samples. To demonstrate the functionality of ‘dampack’, we analyzed the PSA outputs of the cost-effectiveness of different treatment strategies for Clostrioids difficile that compares 48 treatment strategies, sampling 10,000 sets of 51 parameters.

RESULTS : We found six strategies on the efficient frontier, while also indicating strongly and weakly dominated strategies. One-way sensitivity analysis plots show how the optimal strategy changes as model parameters are varied individually. PSA results can additionally be summarized through cost-effectiveness acceptability and expected loss curves. ‘dampack’ also plots the frontier, indicating the optimal strategy in expectation at each willingness-to-pay threshold.

CONCLUSIONS : ‘dampack’ is a powerful and flexible package for the analysis and visualization of CEA results. ‘dampack’ also facilitates the use of state-of-the-art economic evaluation methods, such as value of information analysis, to a broader user-base.