Development and Validation of a Spatial Surge Capacity Assessment Framework for Emergency Departments: Empirical Multi-Hospital Evaluation

Emergency Departments (EDs) are the primary hospital interface during disasters and mass-casualty incidents, yet surge capacity assessments predominantly emphasize workforce and logistics while overlooking measurable spatial determinants. Observations from five tertiary hospitals in India indicate that circulation bottlenecks, incompatible functional adjacencies, and contamination risks can compromise safety and operational performance. This study develops and validates the Spatial Surge Capacity Assessment Framework (SSCAF) to operationalize spatial resilience as a quantifiable dimension of healthcare infrastructure preparedness. A sequential mixed-methods design was applied across five tertiary hospitals using structured spatial walkthroughs; architectural and disaster-planning document review; and focus group discussions involving 81 clinicians, administrators, and facility planners. The outcome of this thematic analysis produced 42 spatial indicators, refined through three Delphi rounds with a multidisciplinary expert panel. Consensus retained 30 key performance indicators (median ≥ 4/5; IQR ≤ 1; Kendall’s W = 0.855; χ² = 297.42; <i>p</i> < 0.001). Content validity was strong (I-CVI 0.75–1.00; S-CVI/Ave = 0.93), and reliability was high (ICC 0.82–0.91), structured into eight operational domains. The resulting weighted scoring matrix standardizes the measurement of spatial surge preparedness. The SSCAF provides an evidence-based audit and planning tool supporting resilient hospital infrastructure. It aligns with the Sendai Framework, enabling governance audits, guiding ED retrofitting, and supporting performance-based evaluation for planners and architects.