OBJECTIVE: Measures of neighborhood disadvantage demonstrate correlations to health outcomes in children. We compared differing indices of neighborhood disadvantage with emergency medical services (EMS) interventions in children. METHODS: We performed a retrospective study of EMS encounters for children (<
18 years) from approximately 2000 US EMS agencies between 2021 and 2022. Our exposures were the Child Opportunity Index (COI
v2.0), 2021 Area Deprivation Index (ADI), and 2018 Social Vulnerability Index (SVI). We evaluated the agreement in how children were classified with each index using the intraclass correlation coefficient. We used logistic regression to evaluate the association of each index with transport status, presence of cardiac arrest, and condition-specific interventions and assessments. RESULTS: We included 738,892 encounters. The correlation between the indices indicated good agreement (intraclass correlation coefficient=0.75). There was overlap in relationships between the COI, ADI, and SVI for each of the study outcomes, both when visualized as a splined predictor and when using representative odds ratios (OR) comparing the third quartile of each index to the lower quartile (most disadvantaged). For example, the OR of non-transport was 1.12 (95% confidence interval [CI]: 1.10-1.14) for COI, 1.18 (95% CI: 1.16-1.20) for ADI, and 1.22 (95% CI: 1.20-1.23) for SVI. CONCLUSION: The COI, ADI, and SVI had good correlation and demonstrated similar effect size estimates for a variety of clinical outcomes. While investigators should consider potential causal pathways for outcomes when selecting an index for neighborhood disadvantage, the relative strength of association between each index and all outcomes was similar.