Speed and Nighttime Usage Restrictions and the Incidence of Shared Electric Scooter Injuries.

Importance: Electric scooter (e-scooter) crashes have become a serious health issue worldwide. The need for effective e-scooter regulations has been established in numerous instances. Objective: To investigate the association of restrictions on top speed and nighttime usage on the incidence of e-scooter-related injuries. Design, Setting, and Participants: A retrospective comparative cohort study of all patients with an injury related to shared e-scooter riding sustained in Helsinki, Finland. Data were collected from the electric patient database from 3 trauma hospitals representing all public hospitals treating patients with acute trauma in Helsinki. Shared e-scooter injuries from 2 periods were compared: an unrestricted period (January 1 to August 31, 2021) and a restricted period (January 1 to August 31, 2022). Data were analyzed from September 2022 to September 2023. Exposures: The restrictions established for shared e-scooters during the restricted period were: (1) the daytime top speed of 20 km/h, as opposed to the previous top speed of 25 km/h, (2) the use of shared e-scooters was prohibited on Friday and Saturday nights between 12 am and 5 am, and (3) the nighttime top speed was decreased to 15 km/h from Sunday to Thursday between 12 am and 5 am, as opposed to 25 km/h. Main outcome: The incidence of e-scooter injuries compared with the total trips made by e-scooters. Results: There were 528 e-scooter injuries requiring hospital care during the unrestricted period and 318 injuries during the restricted period of similar length. The median (IQR) age of the patients in the study periods was 25 (21-32) and 28 (22-37), respectively; 308 (58%) and 191 (60%) were male, respectively. The incidence of e-scooter injuries was 19 (95% CI, 17-20) for every 100 000 rides during the unrestricted period and 9 (95% CI, 8-10) per 100 000 rides during the restricted period. In the risk analysis, the odds ratio for shared e-scooter injuries was 0.5 (95% CI, 0.4-0.6) for the restricted period when adjusted for hourly temperature, rain amount, wind speed, and visibility. After introducing the restrictions, the number of e-scooter injuries decreased significantly between 11 pm and 5 am. Conclusion and Relevance: The number of injuries decreased after implementing restrictions on the top speed and nighttime usage of e-scooters. Similar restrictions in cities with shared e-scooter services should be explored.