A Practical Crash-Outcome Occupant Screening Index for Passenger Vehicles with Data-Limited Crash Data

This article introduces the Crash-Outcome Occupant Screening Index (COSI), a methodology for comparing police-reported harm outcomes among passenger-vehicle occupants involved in reported crashes. COSI estimates the proportion of crash-involved occupants of a given vehicle model who were recorded by police as injured or killed. The index is designed for data-limited crash datasets where detailed injury severity coding, exposure measures, and crash reconstruction variables are unavailable or inconsistent. COSI was applied to five years of police-reported crash data from Iran to examine high-volume passenger-car models in a market with relatively limited model diversity and long production cycles. The results are presented with 95% confidence intervals and supported by year-to-year repeatability and platform-consistency checks. The index is intended as a descriptive screening and prioritization tool, not as a causal measure of vehicle crashworthiness, registration-based risk, or exposure-adjusted injury risk.