SEVERE MATERNAL MORBIDITY

Getting Started: SMM Calculation Guide

Updated October 2026

This step-by-step guide assists analysts in calculating SMM using the methodology developed by a national workgroup with representatives from AHRQ, HRSA, CDC, and AIM. To use this guide, you will also need to download the SMM Code List and SMM Flagging Table below.

Download the Guide (PDF, 325 KB)

SMM Codes List

Updated October 2026

A human-readable reference showing the diagnosis and procedure codes—and code ranges—used to identify each SMM component. Best for reviewing and understanding the SMM code set.

Download the SMM Codes List (XLSX, 146 KB)

SMM Flagging Table

Updated October 2026

A machine-readable version of the SMM code set, with individual codes and flags that can be joined to data to identify SMM components and apply the SMM algorithm.

Download the SMM Flagging Table (XLSX, 234 KB)

SMM Validation Workbook

Updated October 2026

Designed for state health departments, health systems, and hospitals, this package includes test code and synthetic data with known, expected results to help analysts verify their implementation of the SMM calculation algorithm.

Download the SMM Validation Workbook (XLSX, 5.6 MB)

Additional Resources

Federally Available Resource Data (FAD) Resource Document (External)

Healthcare Cost and Utilization Project (HCUP) Fast Stats (External)

Alert on Blood Transfusion Procedure Coding