Associations between changes in population mobility in response to the COVID-19 pandemic and socioeconomic factors at the city level in China and country level worldwide: a retrospective, observational study

SummaryBackground Until broad vaccination coverage is reached and effective therapeutics are available, controlling population mobility (ie, changes in the spatial location of a that affect spread distribution pathogens) one major interventions used to reduce transmission SARS-CoV-2. However, differs across locations, which could effectiveness pandemic control measures. Here we assess extent socioeconomic factors associated with reductions during COVID-19 pandemic, at both city level China country worldwide. Methods In this retrospective, observational study, obtained anonymised daily mobile phone data for 358 Chinese cities from Baidu, 121 countries Google Community Mobility Reports. We assessed intra-city movement intensity, inflow outflow intensity each between Jan 25 (when national emergency response was implemented) Feb 18, 2020 lowest) compared these corresponding lunar calendar period previous year (Feb 5 March 1, 2019). were classified into four index (SEI) groups (high SEI, high–middle middle low SEI) association using univariate multivariable linear regression. At level, six types (residential, transit stations, workplaces, retail recreation, parks, groceries pharmacies) 35 days after implementation same day week baseline (Jan 3 6, 2020). associations country's sociodemographic Findings The reduction stronger higher SEI than those lower (r=–0·47, p<0·0001). inter-city flow (both intensity) not only government country-level analysis, Universal Health Coverage indexes had greater recreation) following declarations indexes. A showed stations (r=–0·27, p=0·0028), workplaces (r=–0·34, p=0·0002), areas recreation (rxs=–0·30, p=0·0012) index. Interpretation Although outbreaks more frequently reported larger cities, our analysis shows future policies should prioritise risks level—eg, by providing financial assistance improving public health messaging. study design allows us associations, long-term needed decipher causality. Funding Ministry Science Technology, Research Council Norway, Beijing Municipal & Technology Commission, Natural Foundation, Advanced Innovation Program Land Surface Science, National Foundation China, Association Technology.