Predicting Hospital Resource Use During COVID-19 Surges: A Simple but Flexible Discretely Integrated Condition Event Simulation of Individual Patient-Hospital Trajectories.

Objectives: To assist with planning hospital resources, including critical care (CC) beds, for managing patients with COVID-19.

Methods: An individual simulation was implemented in Microsoft Excel using a discretely integrated condition event simulation. Expected daily cases presented to the emergency department were modeled in terms of transitions to and from ward and CC and to discharge or death.

Efficiency Model of Cladribine Tablets Versus Infusion-Based Disease-Modifying Drugs for Patients with Relapsing-Remitting Multiple Sclerosis.

Introduction: To develop a simulation model assessing the efficiency of using cladribine tablets versus infusion-based disease-modifying drugs (DMDs) for the treatment of relapsing-remitting multiple sclerosis (RRMS) from a facility perspective in the UK.

Methods: A scheduling algorithm was developed to simulate day-case admissions and calculate the mean changes to resource use and time burden for patients in a facility that transitions from infusion-based treatments to cladribine tablets over 1 year. Model inputs and assumptions were based on previous research and expert opinion.

Cooking Up a Transparent Model Following a DICE Recipe.

When a model is built, it tends to be an iterative process. The ideal model building process starts with constructing a top-level model (that works) and then digging deeper into the sections that need more details. A good model tends to have a long life and be both adapted and updated.

Trusting the Results of Model-Based Economic Analyses: Is there a Pragmatic Validation Solution?

Models have become a nearly essential component of health technology assessment. This is because the efficacy and safety data available from clinical trials are insufficient to provide the required estimates of impact of new interventions over long periods of time and for other populations and subgroups. Despite more than five decades of use of these decision-analytic models, decision makers are still often presented with poorly validated models and thus trust in their results is impaired.

Adding Events to a Markov Model Using DICE Simulation.

Background: Health care decisions are often made under uncertainty and modeling is used to inform the choices and possible consequences. State-transition ("Markov") models are commonly used but they represent the problem solely in terms of states; events are not explicitly considered.

Methods: Discretely integrated condition event (DICE) simulation provides for both aspects that persist over time ("conditions") and for those happening at a point in time ("events").

Validation of a DICE Simulation Against a Discrete Event Simulation Implemented Entirely in Code.

Background: Modeling is an essential tool for health technology assessment, and various techniques for conceptualizing and implementing such models have been described. Recently, a new method has been proposed-the discretely integrated condition event or DICE simulation-that enables frequently employed approaches to be specified using a common, simple structure that can be entirely contained and executed within widely available spreadsheet software. To assess if a DICE simulation provides equivalent results to an existing discrete event simulation, a comparison was undertaken.

The Economic Impact of Lower Protein Infant Formula for the Children of Overweight and Obese Mothers.

The global prevalence of obesity is rising rapidly, highlighting the importance of understanding risk factors related to the condition. Childhood obesity, which has itself become increasingly prevalent, is an important predictor of adulthood obesity. Studies suggest that the protein content consumed in infanthood is an important predictor of weight gain in childhood, which may contribute to higher body mass index (BMI).

Cost-Effectiveness Analysis of Smoking Cessation Interventions in Japan Using a Discrete-Event Simulation.

Background: Smoking cessation medications have been shown to yield higher success rates and sustained abstinence than unassisted quit attempts. In Japan, the treatments available include nicotine replacement therapy (NRT) and varenicline; however, unassisted attempts to quit smoking remain common.

Objective: The objective of this study was to compare the health and economic consequences in Japan of using pharmacotherapy to support smoking cessation with unassisted attempts and the current mix of strategies used.

Long-acting olanzapine versus long-acting risperidone for schizophrenia in Spain - a cost-effectiveness comparison.

Background: In schizophrenia, medication adherence is critical to achieve better patient outcomes and to avoid relapses, which are responsible for a significant proportion of total healthcare costs for this chronic illness. The aim of this study was to assess the cost-effectiveness of olanzapine long-acting injection (OLAI) compared with risperidone long-acting injection (RLAI) in patients with schizophrenia in Spain.

Methods: A discrete event simulation (DES) model was developed from a Spanish healthcare system perspective to estimate clinical and economic outcomes for patients with schizophrenia over a five-year period.

Decision-analytic models: current methodological challenges.

Modelers seeking to help inform decisions about insurance (public or private) coverage of the cost of pharmaceuticals or other health care interventions face various methodological challenges. In this review, which is not meant to be comprehensive, we cover those that in our experience are most vexing. The biggest challenge is getting decision makers to trust the model.

Cost-minimization comparison of darunavir plus ritonavir and lopinavir/ritonavir in HIV-1 infected treatment-naïve women of childbearing age.

Background: Guidelines from the Department of Health and Human Services in the US recommend ritonavir-boosted lopinavir (LPV/r) as a preferred protease inhibitor (PI) for HIV-positive antiretroviral-naїve pregnant women. These guidelines also cite ritonavir-boosted darunavir (DRV + RTV) as an alternative PI in this clinical scenario. The purpose of this analysis was to compare economic outcomes for regimens based on these two treatments.

Lopinavir/ritonavir versus darunavir plus ritonavir for HIV infection: a cost-effectiveness analysis for the United States.

Background: The ARTEMIS trial compared first-line antiretroviral therapy (ART) with lopinavir/ritonavir (LPV/r) to darunavir plus ritonavir (DRV + RTV) for HIV-1-infected subjects. In order to fully assess the implications of this study, economic modelling extrapolating over a longer term is required.

Objective: The aim of this study was to simulate the course of HIV and its management, including the multiple factors known to be of importance in ART.

Modeling using discrete event simulation: a report of the ISPOR-SMDM Modeling Good Research Practices Task Force--4.

Discrete event simulation (DES) is a form of computer-based modeling that provides an intuitive and flexible approach to representing complex systems. It has been used in a wide range of health care applications. Most early applications involved analyses of systems with constrained resources, where the general aim was to improve the organization of delivered services.

Modeling using discrete event simulation: a report of the ISPOR-SMDM Modeling Good Research Practices Task Force-4.

Discrete event simulation (DES) is a form of computer-based modeling that provides an intuitive and flexible approach to representing complex systems. It has been used in a wide range of health care applications. Most early applications involved analyses of systems with constrained resources, where the general aim was to improve the organization of delivered services.

Cost-effectiveness of novel relapsed-refractory multiple myeloma therapies in Norway: lenalidomide plus dexamethasone vs bortezomib.

Objective: To estimate the cost-effectiveness (cost per additional life-year [LY] and quality-adjusted life-year [QALY] gained) of lenalidomide plus dexamethasone (LEN/DEX) compared with bortezomib for the treatment of relapsed-refractory multiple myeloma (rrMM) in Norway.

Methods: A discrete-event simulation model was developed to predict patients? disease course using patient data, best response, and efficacy levels obtained from LEN/DEX MM-009/-010 trials and the bortezomib (APEX) published clinical trial. Predictive equations for time-to-progression (TTP) and post-progression survival (PPS) were developed by identifying the best fitting parametric survival distributions and selecting the most significant predictors.

Discrete event simulation: the preferred technique for health economic evaluations?

Objectives: To argue that discrete event simulation should be preferred to cohort Markov models for economic evaluations in health care.

Methods: The basis for the modeling techniques is reviewed. For many health-care decisions, existing data are insufficient to fully inform them, necessitating the use of modeling to estimate the consequences that are relevant to decision-makers.

Economic and health consequences of managing bradycardia with dual-chamber compared to single-chamber ventricular pacemakers in Italy.

Objective: This study sought to estimate the economic implications of managing bradycardia due to sinoatrial node disease or atrioventricular block with dual compared to single-chamber ventricular pacemakers from an Italian government perspective. Dual-chamber pacemakers lower the risk of developing atrial fibrillation and pacemaker syndrome.

Methods: A discrete event simulation of a patient's course for 5 years following pacemaker implantation.

Invasive meningococcal disease epidemiology and control measures: a framework for evaluation.

Background: Meningococcal disease can have devastating consequences. As new vaccines emerge, it is necessary to assess their impact on public health. In the absence of long-term real world data, modeling the effects of different vaccination strategies is required.

The Danish Civil Registration System. A cohort of eight million persons.

Background: The Danish Civil Registration System (CRS) was established in 1968, where all persons alive and living in Denmark were registered. Among many other variables, it includes individual information on personal identification number, gender, date of birth, place of birth, place of residence, citizenship, continuously updated information on vital status, and the identity of parents and spouses.

Methods: To evaluate the quality and completeness of the information recorded on persons in the CRS, we considered all persons registered on November 4, 2005, i.

Economic implications of growth hormone use in patients with short bowel syndrome.

Objective: Short bowel syndrome is a rare, life-threatening condition that can result in nutritional malabsorption. Parenteral nutrition provides life-saving support but can lead to complications and affect quality of life. Recombinant human growth hormone, somatropin (rDNA origin), has been shown to significantly reduce dependence on nutritional support (p < 0.

Modelling the health benefits and economic implications of implanting dual-chamber vs. single-chamber ventricular pacemakers in the UK.

Aims: To estimate the consequences of managing bradycardia due to sinoatrial node disease or atrioventricular block with dual-chamber vs. single-chamber ventricular pacemakers.

Methods And Results: A discrete-event simulation was conducted to predict outcomes over 5 years.