A new paper, led by ISGlobal researchers and civic engagement specialists from Ideas for Change , describes the first stages of a co-created citizen science epidemiological project in Barcelona. The first stages  include identifying topics that citizens wish to investigate as regards air pollution and health, formulating their concerns into research questions and co-designing the study protocol. This paper also reflects key trade-offs between scientific rigor and public engagement and provides suggestions to consider when applying citizen science to environmental health studies. 


“In environmental health research, citizens are usually involved in collecting data, but rarely in other research steps such as defining the research question or designing the study. The co-created citizen science approach can help to increase collaboration between scientists and lay people by engaging the latter in all phases of research. This approach is rare in environmental epidemiology, thus there are not many documented examples we can learn from.That is the reason why we wanted to write a paper detailing the participatory activities that we have conducted in the framework of the CitieS-Health project and reflect on their advantages and disadvantages. We believe this paper can be helpful for people in the field who wish to build on our experience and engage the lay public in research on air quality and health ”, explained Florence Gignac, researcher at ISGlobal and first author of the paper. 


In this paper, the authors present five activities they have conducted to co-design the research question and the study protocol. First, an online survey on knowledge, perceptions and preferences on topics to be investigated around the theme of air pollution and health was created. A pop-up intervention was held to discuss with citizens their concerns about air pollution and health. Later on, a community meeting was organized to narrow down the research topics and list potential research questions. In an online survey, citizens were asked to vote for the research question they would like to investigate with the experts. A workshop was held to choose a study design in which citizens would like to partake to answer their preferred research question.


According to nearby 500 respondents from the first survey, cognitive and mental health were the main priorities of research. Based on the second survey, with 27% of the votes from 556 citizens, the most popular research question was, “How does air pollution together with noise and green/blue spaces affect mental health?”. “The participants also decided that the study design was an observational study in which citizens provide daily repeated measures of different cognitive and mental health outcomes and relate them to the air pollution concentrations. Overall, despite the fact that the representativeness of our results is subject to limitations, the co-creation activities enabled citizens to provide extensive inputs to the project and are still valuable to inform us on current community concerns”, said Xavier Basagaña, researcher at ISGlobal and main researcher of the CitieS-Health project.


Based on the co-creation activities and the results obtained, the ISGlobal and Ideas for Change team concluded that applying citizen science in an environmental health project is valuable for researchers despite some challenges such as engaging citizens and maximizing representativity.



Co-creating a local environmental epidemiology study: the case of citizen science for investigating air pollution and related health risks in Barcelona, Spain. Florence Gignac, Valeria Righi, Raül Toran, Lucía Paz Errandonea, Rodney Ortiz, Mark Nieuwenhuijsen, Javier Creus, Xavier Basagaña & Mara Balestrini. Environmental Health volume 21, Article number: 11 (2022)