NPLB’s GCEA Calculator
Senior Health Economist
NPLB’s GCEA Calculator
By Richard Xie
Photo by Sam Balye on Unsplash
May 15th, 2025
If you’re a regular Rapport reader, you’ll have heard us say plenty about Generalized Cost-Effectiveness Analysis (GCEA) and why we think it offers a better approach than traditional CEA (TCEA) models in better capturing the comprehensive societal value of innovative medicines.
To truly appreciate the advances offered by GCEA, there’s nothing as illustrative as getting in there and running the numbers yourself. However, building a de-novo cost-effectiveness model can be a daunting task.
Well, not to worry! Just in time for the ISPOR Annual Meeting 2025, we’ve released an easy-to-use GCEA calculator that allows you to explore and appreciate the societal value of innovative medicines, and underpin the key value drivers without building a full-on model. The GCEA calculator offers an interactive user interface that lets you customize your own GCEA.
Below, we give a little tour of how it works using Jardiance in the treatment of Type 2 diabetes as an example. I’ve also given a detailed tutorial on how to get the most out of the calculator here.
But we encourage you to get in there and try it for yourself!
Welcome to the NPLB GCEA calculator! The homepage briefly explains the calculator’s purpose and provides links to key GCEA resources.
After you’ve clicked, “Ready? Let’s Go!,” You’ll be taken to this page where you can choose from our pre-filled case studies, or start from scratch with your own custom GCEA.
Today, we’ll be focusing on the Jardiance case study for illustrative purposes.
Down the left hand side of the interface are expandable input menus. A customizable output graph is generated on the right.
We’ll be using the Advanced Mode in this demonstration. This set-up provides a detailed view for inputs and allows for more customization. Note, this does not impact the base calculations being done.
Basic Inputs are similar to what you might see in a traditional cost-effectiveness analysis, such as costs and efficacy.
Inputs used in this section were based on the ICER assessment.
The Productivity menu covers inputs that quantify productivity impacts for the patient and coworkers as a result of effective treatment (Jardiance, in this case).
Input values for comparator were derived from the literature in our case study, and the inputs for Jardiance were calculated as the product of the input for the comparator and the ratio of medical cost savings of Jardiance versus the comparator.
The Caregiver Curden inputs cover the impact on the patients’ caregivers — both professionals, like nurses, and loved ones — and how much time the treatments lessen their burden (e.g., productivity impacts, out-of-pocket spending).
Similarly, the inputs were derived based on the literature and the ratio of medical cost savings of Jardiance versus the comparator.
The Health Equity menu addresses how Jardiance might close gaps in health outcomes between different patient subgroups.
Here you can choose to use inputs from published studies or enter the data manually, as well as what method of social welfare function specification you’d rather use.
The Risk Reduction inputs serve to quantify how disease severity and health risk aversion might impact the value of health gains to patients.
Inputs for Jardiance were derived from published literature and assumptions.
Inputs in the Dynamics section illustrate how the price of the drug might change due to generic competition following loss of exclusivity and changes in the future incident patient populations.
It also allows users to estimate option value, the value of the chance to access future treatments as a result of improved quality of life or extended life years.
The social discount rate better reflects how we value future health gains today. Two percent was used for the US-based model based on the latest empirical research in this area.
The Additional Considerations menu addresses how the new treatment might affect the rest of the community, such as with infectious disease and vaccines. It also addresses additional, non-medical costs incurred, such as transportation to hospitals.
In this case, again, direct non-medical costs are based on published literature and the ratio of medical costs.
By default, the output graph will portray a detailed view of the results using ICER as the primary outcome. The detailed graph displays the contribution of each value domain to the additional societal value from GCEA analysis.
You can adjust which outcomes you’d like to measure between ICER, net monetary benefit, and value based pricing.
You can also simplify the output graph for a bottom-line analysis.