Health impacts of bike-sharing systems in the US

Strength of evidence: Moderate
Consistency with other evidence: High
Plausible Causal Pathway: Yes

The study quantifies the health risks and benefits of bike-sharing schemes (or bike-sharing systems) in the USA and New York City.

They defined bike-sharing schemes as short-term loans of bikes that are picked up at one location and then used and dropped off at another location. In 2019, nearly 110,000 bike sharing trips were made every day in the US and almost 55,000 of these were in New York City.

The study estimated the impacts of the bike-sharing schemes on physical activity, air pollution and traffic incidents.

They estimated that annually 4.7 premature deaths were saved in the USA with 2 premature deaths saved in New York City; 737 Disability-Adjusted Life-Years (DALYs) were reduced in the USA, with 355 DALYs reduce din New York City; and US$36,000,000 saved in health economic impacts in the uSA, with US$15,000,000 saved in New York City.

The quantification of the health impacts of a bike-sharing scheme found that:

  • Physical activity was the main influence on reducing adversity health impacts

  • The health benefits of trips made using a bike-sharing scheme are larger than the health risks.

  • Bike-sharing trips do provide health benefits for cyclists.

Source: Clockston, R.L.M. And Rojas-Rueda, D. (2021) ‘Health impacts of bike-sharing systems in the US’, Environmental Research, 2020, 111709. https://doi.org/10.1016/j.envres.2021.111709 | Open Access |

Concept: Disability-Adjusted Life-Years (DALYs) are used to measure and compare the burden of disease within groups within a population as well as across populations. Mortality only captures deaths but not how many people are living with physical and mental health conditions that negatively affect their quality of life.

“a time-based measure that combines years of life lost due to premature mortality (YLLs) and years of life lost due to time lived in states of less than full health, or years of healthy life lost due to disability (YLDs). One DALY represents the loss of the equivalent of one year of full health. Using DALYs, the burden of diseases that cause premature death but little disability (such as drowning or measles) can be compared to that of diseases that do not cause death but do cause disability (such as cataract causing blindness).”

Further Information: World Health Organization (2021) Disability-Adjusted Life-Years (DALYs). Available at: https://www.who.int/data/gho/indicator-metadata-registry/imr-details/158 (Accessed: 26 July 2021).

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