(I'm OP of this submission, but otherwise unrelated to the story so can't answer questions on it.) The article also contains a link to the source study, "Impac

(I'm OP of this submission, but otherwise unrelated to the story so can't answer questions on it.) The article also contains a link to the source study, "Impacts of ambient air quality on acute asthma hospital admissions during the COVID-19 pandemic in Oxford City, UK: a time-series study" - https://bmjopen.bmj.com/content/14/1/e070704 https://bmjopen.bmj.com/content/14/1/e070704 Which includes: "STRENGTHS AND LIMITATIONS OF THIS STUDY - This study investigated the association between ambient air pollution exposure and risk of admission to hospital for asthma. - The study includes an at-risk population of >800,000 person-years. - Associations were evaluated using single and multipollutant models. - Causation cannot be inferred from this observational study. - A single city study may limit wider generalisation of findings." (And I didn't exactly use the original article title despite it being a perfect 80chars, to be able to include the 41% figure - from "Asthma emergency admissions plunged as lockdown improved air, Oxford study finds".)