# Bayesian Models to Generate Small Area Estimates of Population Health: Tutorial for Using Rate Stabilizing Tools and Their Output

## TL;DR

This paper introduces two tools, RSTbx and RSTr, to help public health professionals calculate reliable small area health estimates using Bayesian models, improving data quality for local health planning.

## Contribution

The novel contribution is the development and tutorial demonstration of two accessible tools for Bayesian small area estimation with built-in age-standardization and reliability evaluation.

## Key findings

- The tools reduce the number of geographic units with suppressed estimates by improving statistical reliability.
- Users can customize reliability thresholds and generate credible intervals for comparing geographic units.
- Census tract-level maps from North Carolina and Rhode Island demonstrate the tools' effectiveness in real-world data.

## Abstract

The demand for high-quality population health data at the local level calls for expanded tools for those working to enhance the health of communities across the country to easily calculate small area estimates. Statistical models that generate small area estimates often use Bayesian estimation techniques, which are computationally complex and not readily accessible to most public health professionals. We developed 2 tools to facilitate small area estimation. For ArcGIS Pro users, we developed the Rate Stabilizing Toolbox ArcGIS plugin (RSTbx), and for R users, we developed the Rate Stabilizing Tool R package (RSTr). In this tutorial, we demonstrate how to use these tools to calculate small area estimates and evaluate their reliability. We also demonstrate 3 key benefits from using either of these tools: (1) decreased number of geographic units with suppressed estimates, (2) flexibility to set the threshold for statistical reliability, and (3) credible intervals that can be used to identify statistically significant differences between geographic units. Additionally, both tools offer built-in age-standardization capabilities. We created census tract–level maps from North Carolina mortality data and Rhode Island hospitalization data to showcase the benefits of generating small area estimates with these tools. Rate Stabilizing Toolbox and Rate Stabilizing Tool for R are powerful tools that can be used to meet the demand for high-quality local-level data to inform public health programs and tailor health promotion activities to the needs of communities across the country.