The causal effect of private transport on life satisfaction among older adults and the mediation effect of social participation in China

Private transport constitutes the prerequisite for the freedom of mobility and facilitates accessibility for activities of older adults. Abundant studies have been conducted on the association between car ownership and life satisfaction in Western countries where cars dominate private transport. However, as the most prevalent and conventional private transport in China, cars and e-bikes have not received adequate attention. Using 2015 and 2018 datasets from the China Health and Retirement Longitudinal Study, we apply the Propensity Score Matching-Difference in Differences to investigate how private transport influences the multi-dimensional life quality of older adults. Furthermore, we focus on the mediation effect of social participation on the above causal effect. Our findings reveal that car and e-bike ownership have a causal impact on older adults' life satisfaction, while the influence of e-bike ownership is multi-dimensional. The relationship between car ownership and life satisfaction is mediated by social participation regarding exercise and voluntary activities. However, the mediation effects of mahjong and exercise activities are statistically significant between e-bike ownership and the multi-dimensional life quality of older adults. Understanding the life quality of older adults related to private transport is essential for guiding travel mobility and the life quality of older adults in China.