Study Protocol for the Evaluation of the Health Effects of Superblocks in Barcelona: The “Salut Als Carrers” (Health in the Streets) Project

Superblocks are currently being introduced in Barcelona to respond to the city’s scarcity of green spaces and high levels of air pollution, traffic injuries, and sedentariness. The aim is to calm the streets by reducing the number of square meters dedicated to private vehicles and to reclaim part of this public space for people. Salut als Carrers (Health in the Streets) is a project to evaluate the potential environmental and health effects of the superblock model with an equity perspective in Barcelona. This study aims to explain the various interventions implemented in different neighborhoods in Barcelona and the methods that will be used to evaluate them in a quasi-experimental and health impact assessment (HIA) approaches. Given the complexity of the intervention evaluated, the project employs mixed methodologies. Quantitative methods include: (a) a pre–post health survey of 1200 people randomly selected from the municipal register asked about self-perceived health and quality of life, social support, mental health, mobility, physical activity, neighborhood characteristics, and housing; (b) pre–post environmental measurements, mainly of nitrogen dioxide (NO(2)), particulate matter of less than 10 µm (PM(10)), and particulate matter of less than 2.5 µm (PM(2.5)) and black carbon; (c) pre–post environmental walkability measures using the Microscale Audit of Pedestrian Streetscapes (MAPS) tool; (d) use of public space and physical activity levels using the System for Observing Play and Recreation in Communities (SOPARC), a validated observation tool; (e) pre–post traffic injury measures with a comparison group; and (f) the comparison and integration of pre–post assessment with previous HIAs and the improvement of future HIAs. Qualitative studies will be performed to analyze residents’ perception of these effects by using: (a) various focus groups according to different participant characteristics who are more or less likely to use the superblocks; and (b) a guerrilla ethnography, which is a method that combines ethnographic observation and semi-structured interviews. This study, which evaluates the impact of an ambitious urban-renewal program on health, will help to assess the effectiveness of public policy in terms of health and health inequalities.