He Dongsheng, Sun Guibo, De Vos Jonas, Webster Chris
Urban Analytics and Interventions Research Lab, Department of Urban Planning and Design, The University of Hong Kong, Hong Kong Special Administrative Region, China.
Urban Analytics and Interventions Research Lab, Department of Urban Planning and Design, The University of Hong Kong, Hong Kong Special Administrative Region, China.
Health Place. 2022 Nov;78:102939. doi: 10.1016/j.healthplace.2022.102939. Epub 2022 Nov 11.
This paper provides causal inference on how transport intervention affects moderate-to-vigorous physical activity (MVPA) and walking among older adults using a natural experiment of a new metro line in Hong Kong. A longitudinal survey of 449 cohort participants was collected before and after the metro operation. Treatment groups live within a 400m walking buffer of the new metro stations, while control groups are located around comparable stations on existing metro lines. These metro lines were planned at the same time using similar principles, but the intervention line was built later due to different financial models. Our difference-in-difference (DID) models found that the new metro line significantly decreased older adults' weekly MVPA (-129.33 min, p < 0.05) in treatment groups, while the effect on change in walking time did not significantly differ between the treatment and control groups. We also found heterogeneous treatment effects among gender and age subgroups. Furthermore, our time effect tests suggested that older adults' physical activity and walking levels may stabilise, based on participants living around a metro station operated four years ago with another comparable station operated three decades ago. This practice-based evidence suggests that new metro developments might not promote physical activity and walking levels among older adults in the high-density city of Hong Kong.
本文利用香港一条新地铁线路的自然实验，对交通干预如何影响老年人的中度至剧烈身体活动（MVPA）和步行情况进行了因果推断。在地铁运营前后，对449名队列参与者进行了纵向调查。治疗组居住在新地铁站400米步行缓冲区内，而对照组位于现有地铁线路上类似的车站周围。这些地铁线路是同时按照类似原则规划的，但由于不同的融资模式，干预线路建设较晚。我们的双重差分（DID）模型发现，新地铁线路使治疗组老年人的每周MVPA显著减少（-129.33分钟，p<0.05），而治疗组和对照组在步行时间变化方面的影响没有显著差异。我们还发现了性别和年龄亚组之间的异质性治疗效果。此外，我们的时间效应测试表明，根据居住在四年前运营的地铁站周围以及另一个三十年前运营的类似车站周围的参与者情况，老年人的身体活动和步行水平可能会趋于稳定。这一基于实践的证据表明，在高密度城市香港，新地铁建设可能不会促进老年人的身体活动和步行水平。
