Does Motorized Two-Wheeler Body Style Affect Crash Risk in New Delhi, India?

Road traffic injuries are a leading cause of death globally, with a disproportionate burden in low- and middle-income countries (LMICs). In many LMIC cities, motorized two-wheelers—particularly scooters and motorcycles—account for a substantial share of fatalities, yet evidence on safety differences by body style remains limited. This study estimates the association between scooter versus motorcycle body style and fatal crash involvement in New Delhi, India. A spatially matched case-control design was employed in Delhi National Capital Territory (NCT). Cases were identified from First Information Reports (FIRs) filed between January 2024 and May 2025. Controls were collected through observational sampling of two-wheeler license plate numbers at 67 geospatially stratified road segments, randomly selected from Delhi NCT's 180 police jurisdictions. Sampling strata were defined by the intersection of 11 districts and 3 distance buffers (0–10 km, 10–20 km, 20–35 km) from the city center. Body style was identified using a national vehicle registry and publicly available vehicle model descriptions. Conditional logistic regression was used to estimate associations between body style and fatal crash involvement, adjusting for engine capacity and vehicle age. Scooters were associated with significantly lower odds of fatal crash involvement than motorcycles, including after adjustment for engine capacity and vehicle age (adjusted OR ≈ 0.67, p < 0.05). Higher engine capacity was associated with increased odds of fatal crash involvement, while vehicle age was not significantly associated with risk. To our knowledge, this study provides the first empirical evidence from an LMIC setting that scooters may have a lower risk of fatal crash involvement than motorcycles. Future research should assess whether these patterns hold across other LMIC contexts, but these results address a major evidence gap in two-wheeler safety research. These findings may inform body style design standards and contribute to the development of more effective road safety policies.