Interactive Shiny Dashboard

Overview

htaBIM ships with a fully interactive Shiny dashboard that lets you build, explore, and export a budget impact model entirely through a point-and-click interface — no R code required.

The app is built with bslib (Bootstrap 5) for a clean, modern layout and works in any desktop browser.

Launch locally

If you have the package installed, launch the app with one line:

htaBIM::launch_shiny()

Required packages are listed in the Suggests field of DESCRIPTION; the app will prompt you if anything is missing.

Live demo

Deploy your own copy to shinyapps.io (see the Deployment section below) or run the app locally with htaBIM::launch_shiny().

App structure

The dashboard is organised into six tabs:

Tab	What it does
Model Setup	Enter all inputs: population funnel, up to 3 treatments, costs, payer, and uptake dynamics
Results	KPI cards (Year 1 / final year / cumulative), annual and cumulative line plots, interactive results table
Market Shares	Stacked bar chart comparing current vs. new-drug scenario across years
Sensitivity	One-way DSA with tornado diagram + Probabilistic Sensitivity Analysis (Monte Carlo)
Scenarios	Side-by-side scenario comparison table and per-patient cost breakdown chart
Report	Plain-text and HTML report download

Model Setup tab

Population funnel

Input	Description
Indication / disease	Free-text label for the condition
Reference country	Selects built-in population data (GB, US, CA, DE, FR, IT, AU, JP) or custom entry
Prevalence	Point prevalence as a proportion of the reference population
Diagnosed rate	Proportion of prevalent patients with a diagnosis
Treated rate	Proportion of diagnosed patients receiving any treatment
Eligible rate	Proportion of treated patients eligible for the new drug
Growth rate	Annual growth in the eligible population
Projection horizon	Number of years (1–10)

Treatments

Up to three treatments are supported:

New drug — name, target market share at end of horizon (%), and uptake dynamics
Comparator 1 — always required; represents the main standard of care
Comparator 2 — optional second comparator (tick the checkbox to enable)

Four uptake dynamics are available: linear ramp, logistic (S-curve), step change, and constant.

Scenario variants (conservative / optimistic peak shares) are defined in this tab and propagate through all analyses.

Costs & payer

Input	Description
Drug costs	Annual list price per treatment
Administration cost	Annual infusion / injection cost for new drug
Monitoring cost	Annual monitoring cost for new drug
AE cost	Expected annual adverse event cost for new drug
Rebate	Confidential price discount on new drug (%)
Payer perspective	Generic healthcare system, NHS England, CADTH, or US commercial
Currency	GBP, USD, EUR, CAD, AUD, JPY
Discount rate	Applied to Year 2+ costs

Sensitivity tab

Deterministic sensitivity analysis (DSA)

Set low/high ranges for:

Prevalence
Diagnosed rate
Eligible rate
New drug cost multiplier

Then click Run DSA. A tornado diagram and interactive results table are shown for the selected year.

Probabilistic sensitivity analysis (PSA)

Set standard errors (for epidemiology rates, sampled from Beta distributions) and a coefficient of variation (for costs, sampled from LogNormal distributions), choose the number of simulations, and click Run PSA.

A histogram of simulated budget impacts is shown with the base-case value and 95 % credible interval marked.

Deployment to shinyapps.io

To host your own public copy:

Install rsconnect:
```
install.packages("rsconnect")
```

Connect your shinyapps.io account:

rsconnect::setAccountInfo(
  name   = "<your-account>",
  token  = "<token>",
  secret = "<secret>"
)

Deploy the bundled app:

rsconnect::deployApp(
  appDir  = system.file("shiny/htaBIM_app", package = "htaBIM"),
  appName = "htaBIM"
)

Copy the resulting URL and add it to your vignette or dossier.

Linking from pkgdown

Once the pkgdown site is deployed to GitHub Pages (via the supplied GitHub Actions workflow), this vignette renders as an article at:

https://<org>.github.io/htaBIM/articles/shiny-app.html

You can embed the shinyapps.io link in any article, the README, or the _pkgdown.yml navbar.