arxiv – Supplemental material for A Multidimensional Array Representation of State-Transition Model Dynamics

Supplemental material, arxiv for A Multidimensional Array Representation of State-Transition Model Dynamics by Eline M. Krijkamp, Fernando Alarid-Escudero, Eva A. Enns, Petros Pechlivanoglou, M.G. Myriam Hunink, Alan Yang and Hawre J. Jalal in Medical Decision Makin

An Introductory Tutorial on Cohort State-Transition Models in R Using a Cost-Effectiveness Analysis Example

Decision models can combine information from different sources to simulate the long-term consequences of alternative strategies in the presence of uncertainty. A cohort state-transition model (cSTM) is a decision model commonly used in medical decision making to simulate the transitions of a hypothetical cohort among various health states over time. This tutorial focuses on time-independent cSTM, in which transition probabilities among health states remain constant over time. We implement time-independent cSTM in R, an open-source mathematical and statistical programming language. We illustrate time-independent cSTMs using a previously published decision model, calculate costs and effectiveness outcomes, and conduct a cost-effectiveness analysis of multiple strategies, including a probabilistic sensitivity analysis. We provide open-source code in R to facilitate wider adoption. In a second, more advanced tutorial, we illustrate time-dependent cSTMs

STM_diagram_cohort_approach – Supplemental material for A Multidimensional Array Representation of State-Transition Model Dynamics

Supplemental material, STM_diagram_cohort_approach for A Multidimensional Array Representation of State-Transition Model Dynamics by Eline M. Krijkamp, Fernando Alarid-Escudero, Eva A. Enns, Petros Pechlivanoglou, M.G. Myriam Hunink, Alan Yang and Hawre J. Jalal in Medical Decision Makin

A Multidimensional Array Representation of State-Transition Model Dynamics

Cost-effectiveness analyses often rely on cohort state-transition models (cSTMs). The cohort trace is the primary outcome of cSTMs, which captures the proportion of the cohort in each health state over time (state occupancy). However, the cohort trace is an aggregated measure that does not capture information about the specific transitions among health states (transition dynamics). In practice, these transition dynamics are crucial in many applications, such as incorporating transition rewards or computing various epidemiological outcomes that could be used for model calibration and validation (e.g., disease incidence and lifetime risk). In this article, we propose an alternative approach to compute and store cSTMs outcomes that capture both state occupancy and transition dynamics. This approach produces a multidimensional array from which both the state occupancy and the transition dynamics can be recovered. We highlight the advantages of the multidimensional array over the traditional cohort trace and provide potential applications of the proposed approach with an example coded in R to facilitate the implementation of our method

2D_time_memory_relative – Supplemental material for A Multidimensional Array Representation of State-Transition Model Dynamics

Supplemental material, 2D_time_memory_relative for A Multidimensional Array Representation of State-Transition Model Dynamics by Eline M. Krijkamp, Fernando Alarid-Escudero, Eva A. Enns, Petros Pechlivanoglou, M.G. Myriam Hunink, Alan Yang and Hawre J. Jalal in Medical Decision Makin

STM_diagram_array – Supplemental material for A Multidimensional Array Representation of State-Transition Model Dynamics

Supplemental material, STM_diagram_array for A Multidimensional Array Representation of State-Transition Model Dynamics by Eline M. Krijkamp, Fernando Alarid-Escudero, Eva A. Enns, Petros Pechlivanoglou, M.G. Myriam Hunink, Alan Yang and Hawre J. Jalal in Medical Decision Makin

3D_time – Supplemental material for A Multidimensional Array Representation of State-Transition Model Dynamics

Supplemental material, 3D_time for A Multidimensional Array Representation of State-Transition Model Dynamics by Eline M. Krijkamp, Fernando Alarid-Escudero, Eva A. Enns, Petros Pechlivanoglou, M.G. Myriam Hunink, Alan Yang and Hawre J. Jalal in Medical Decision Makin

STM_diagram_traditional_approach – Supplemental material for A Multidimensional Array Representation of State-Transition Model Dynamics

Supplemental material, STM_diagram_traditional_approach for A Multidimensional Array Representation of State-Transition Model Dynamics by Eline M. Krijkamp, Fernando Alarid-Escudero, Eva A. Enns, Petros Pechlivanoglou, M.G. Myriam Hunink, Alan Yang and Hawre J. Jalal in Medical Decision Makin

3D_memory – Supplemental material for A Multidimensional Array Representation of State-Transition Model Dynamics

Supplemental material, 3D_memory for A Multidimensional Array Representation of State-Transition Model Dynamics by Eline M. Krijkamp, Fernando Alarid-Escudero, Eva A. Enns, Petros Pechlivanoglou, M.G. Myriam Hunink, Alan Yang and Hawre J. Jalal in Medical Decision Makin