Methodology description for Health Benefits
For the calculation of health benefits of cycling we used the HEAT tool, which was built to to produce an estimate of the annual benefit (per cyclist; per trip; and total annual benefit) due to reduced mortality as a result of cycling.
If x people regularly walk or cycle an amount of y, what is the economic value of the health benefits resulting from the reduction in mortality caused by their physical activity?
Thus, to estimate the economic value of the health benefits of cycling in the portuguese municipalities * the following methodology was applied:
1. Type of assessment: comparing scenario A versus scenario B:
This option is used to assess the impact of a real intervention or hypothetical scenarios. In this case, it was necessary to insert in the HEAT tool the input data for the two cases: "reference case" and the "comparison case".
Reference case: 2011 Census.
Comparison case: ITDP Scenario1 that establishes an increase of 0.2 percentage points per year (representing a 2.02% increase of cycling modal share in 10 years), the modal distribution by means of transport was recalculated, assuming that the increase of bicycle use represents 2 :
- 20% walking
- 30% use of individual motorized transport (car and motorcycle)
- 50% use of public transport (bus and metro)
2. Time Scale
Year of the reference case: 2011
Year of comparison case: 2021
How long the data should be calculated: 10 years
3. Type of Impacts to be measured: Physical activity and Air pollution
To calculate the health benefits of physical activity, the HEAT tool uses estimates of the relative risk of death from any cause among regular cyclists compared to people who do not cycle regularly. The method used for the quantitative assessment of air pollution risks was established to serve as a basis for assessing the effects of air pollution on cyclists. This method uses PM2.5 as a measure of air pollution. The relative risks for mortality and physical activity used by HEAT were extracted from studies carried out in environments where participants were exposed to (different levels) of air pollution. As such, the relative risks for physical activity include a medium degree of air pollution when cycling. However, in the joint assessment of air pollution and physical activity, the HEAT tool adjusts the relative risk of cycling to exclude the effects of air pollution, using risk estimates adjusted to what they would be if the studies of physical activity had been conducted in unpolluted environments. More information at: https://www.heatwalkingcycling.org/#userguidet
4. Data for the reference case VS comparison case (cycling modal share)
- Population: as the HEAT only includes the adult population (20 - 64 years), the data used from the 2011 Census was: employed population by main mean of transport and according to the journey length from place of residence to place of work
- Cycling modal share
- Total volume of trips per day: sum of trips for all modes of transport multiplied by 2, assuming two trips per day (one way / home / work).
- Distance traveled by bicycle.
5. Proportion of new trips: there are no new trips, there is transfer from other modes of transport.
6.Proportion of trips made for transport VS recreational: all bicycle trips as transport when traveling home / work.
7. Take-up time (in years) until the maximum volume of active travel is reached. (comparison scenario): 10 years
7. Other adjustments: proportion “in traffic” in the absence of detailed information by municipality it was assumed that 50% of trips take place in places with “traffic”
8. Parameters established by the HEAT tool:
- mortality rate (value for Portugal for the 20-64 population) - 268.0725 (deaths / inhabitants);
- value of a statistical life in Portugal (2015) - 1828524,3697 (euros / death) with a discount rate of 5%.
9. Edited parameters:
Average bicycle speed: 15 Km / h
PM 2.5 concentrations: an average of 7.9 was assumed for all municipalities, calculated based on data available on the APA platform (https://qualar.apambiente.pt/estatisticas) for 2015 (middle of 2011 and 2021).
10. General Results (physical activity + air pollution):
Premature deaths avoided per year
Value per year (€)
Value 10 years with a 5% discount rate (€)
*Note: considering the population available data and the modal distribution, it was not possible to calculate the economic health benefits for the following municipalities:
Freixo de Espada à Cinta
Mesão Frio
Penedono
Barrancos
Corvo
Laje das Flores
Lagoa
Nordeste
Porto Moniz
Santana
São Vicente
References
1McDonald, Z., Fulton, L., & Mason, J. (2015). A Global High Shift Scenario: The Potential for Dramatically Increasing Bicycle and E-bike Use in Cities Around the World, with Estimated Energy, CO2, and Cost Impacts. In International Journal for Sustainable Transportation (Issue November). https://www.itdp.org/wp-content/uploads/2015/11/A-Global-High-Shift-Cycling-Scenario_Nov-2015.pdf
2Marqués, R., Hernández-Herrador, V., Calvo-Salazar, M., & García-Cebrián, J. A. (2015). How infrastructure can promote cycling in cities: Lessons from Seville. Research in Transportation Economics, 53, 31–44. https://doi.org/10.1016/j.retrec.2015.10.017