# Propensity score analysis using the freely available user-friendly software EZR (Easy R)

## TL;DR

EZR is a free, user-friendly statistical software that simplifies complex analyses like propensity score matching for researchers.

## Contribution

The paper introduces procedures for performing propensity score analysis using the EZR software.

## Key findings

- EZR supports PS matching and inverse probability weighting for causal inference.
- PS analysis in EZR is compared with conventional multivariate methods.
- EZR has been widely adopted, with over 14,000 citations as of 2025.

## Abstract

EZR (Easy R) is a statistical software package that is freely available on our website (https://www.jichi.ac.jp/usr/hema/EZR/statmed.html) and can be used on both Windows (Microsoft Corporation, USA) and macOS (Apple, USA) systems. EZR is built on R and R Commander and offers a range of statistical functions, including survival analyses with competing risks or time-dependent covariates, receiver operating characteristic curve analyses, meta-analyses, and sample size calculations, all accessible through a point-and-click graphical interface. A previous report that described the installation and basic operation of EZR (“Investigation of the freely available easy-to-use software ‘EZR’ for medical statistics”, Bone Marrow Transplant, 2013) has been cited in more than 14,000 scientific papers as of November 2025. This report describes the procedures for performing propensity score (PS) analysis, including PS matching and inverse probability weighting, and compares these approaches with conventional multivariate analyses.