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Public transit and depression among older adults: using agent-based models to examine plausible impacts of a free bus policy

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Yong Yang, Brent A. Langellier, Ivana Stankov, Jonathan Purtle, Katherine L. Nelson, Erica Reinhard, Frank J. Van Lenthe, Ana V. Diez Roux

Original languageEnglish
Pages (from-to)875-881
Number of pages7
JournalJournal of Epidemiology and Community Health
Issue number11
Published1 Nov 2020

King's Authors


BACKGROUND: Daily transport is associated with mental health. A free bus policy (FBP) may be effective in promoting the use of public transit in older adults and be associated with reductions in depressive symptoms. METHODS: We developed an agent-based model and grounded it using empirical data from England to examine the impact of an FBP on public transit use and depression among older adults. We also used the model to explore whether the impact of the FBP bus use and depression is modified by the type of income segregation or by simultaneous efforts to improve attitudes towards the bus, to reduce waiting times or to increase the cost of driving via parking fees or fuel price. RESULTS: Our model suggests that improving attitudes towards the bus (eg, campaigns that promote bus use) could enhance the effect of the FBP, especially for those in proximity to public transit. Reducing wait times could also significantly magnify FPB impacts, especially in those who live in proximity to public transit. Contrary to expectation, neither fuel costs nor parking fees significantly enhanced the impact of the FBP. The impact of improving attitudes towards the bus and increasing bus frequency was more pronounced in the lower-income groups in an income segregation scenario in which destination and public transit are denser in the city centre. CONCLUSION: Our results suggest that the beneficial mental health effects of an FBP for older adults can be magnified when combined with initiatives that reduce bus waiting times and increased spatial access to transit.

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