State-Level Estimates of Nonfatal Firearm Injury Hospitalizations, 2000–2021

<b>Objectives.</b> To create a comprehensive, publicly available data set of state-level nonfatal firearm injury inpatient hospitalizations (NFIIHs) in the United States from 2000 to 2021. <b>Methods.</b> We used Bayesian modeling to impute missing NFIIH rates for 334 state-year observations and correct for incomplete injury mechanism coding in 766 observations. <b>Results.</b> NFIIH rates increased nationally, with the largest rise between 2019 and 2020, up by one third to reach 1.31 (95% credibility interval [CrI] = 1.27, 1.35) per 10 000 population. State prevalences ranged from 0.18 (95% CrI = 0.14, 0.22) in Hawaii to 2.18 (2.04, 2.33) in Louisiana. South Central states (Mississippi, Arkansas, Missouri) had the largest increases. Twelve states-predominantly in the Northeast and West-experienced decreases. NFIIH rates correlated more strongly with firearm homicide rates (correlation = 0.86) than other intents (correlations < 0.28). Nationwide, there were 2.4 NFIIHs for every firearm homicide, but this ratio varied more than fourfold across states. <b>Conclusions.</b> NFIIH rates varied substantially across and within states. Despite strong correlation, many states diverged from the national NFIIH to firearm homicide ratio. <b>Public Health Implications.</b> Firearm deaths systematically underrepresent serious firearm injuries in some states. This new data set can inform how policies affect serious firearm injuries and injury lethality. (<i>Am J Public Health</i>. 2025;115(7):1106-1114. https://doi.org/10.2105/AJPH.2025.308069).