| { | |
| "original_study": { | |
| "claim": { | |
| "hypothesis": "The implementation of government social distancing measures is associated with a reduction in urban mobility.", | |
| "hypothesis_location": "The expectation is introduced in the background and study aim where the authors state that they analyze mobility data to assess the effect of government social distancing measures on movement in cities.", | |
| "statement": "The analysis shows that government social distancing measures are associated with a substantial additional reduction in city mobility, beyond the general downward time trend in mobility.", | |
| "statement_location": "Results para describing the multilevel mixed-effects regression results, where the authors report the estimated effect of social distancing measures on the Citymapper Mobility Index.", | |
| "study_type": "Observational" | |
| }, | |
| "data": { | |
| "source": "Citymapper Mobility Index (CMI) data combined with information on government social distancing measures compiled from official government and media sources.", | |
| "wave_or_subset": "Daily city-level observations from March 2, 2020 to March 26, 2020.", | |
| "sample_size": "1025 observations across 41 cities.", | |
| "unit_of_analysis": "City-day.", | |
| "access_details": "Citymapper Mobility Index data are publicly available via Citymapper; access procedures are not further detailed.", | |
| "notes": "The CMI is based on planned trips using the Citymapper application and reflects mobility related to public transport, walking, biking, and ride-sharing, but not private automobile use. Cities are classified as having implemented social distancing measures if non-essential businesses were closed, with measures further categorized as moderate or intense." | |
| }, | |
| "method": { | |
| "description": "The study estimates the association between social distancing policies and changes in urban mobility using longitudinal city-level mobility data and regression modeling.", | |
| "steps": [ | |
| "Download daily Citymapper Mobility Index data for 41 cities from March 2 to March 26, 2020.", | |
| "Compile dates and intensity of government social distancing measures for each city using official and media sources.", | |
| "Classify social distancing measures as present or absent, and further as moderate or intense.", | |
| "Construct a longitudinal dataset with repeated daily observations for each city.", | |
| "Estimate a multilevel mixed-effects linear regression model including time trends and social distancing indicators." | |
| ], | |
| "models": "Multilevel mixed-effects linear regression model with city-level repeated observations.", | |
| "outcome_variable": "City mobility measured by the Citymapper Mobility Index (percentage relative to baseline).", | |
| "independent_variables": "Indicator for implementation of social distancing measures; time (day).", | |
| "control_variables": "Time trend (days since March 2, 2020).", | |
| "tools_software": "not stated" | |
| }, | |
| "results": { | |
| "summary": "City mobility declined steadily over time and decreased substantially more in cities after the introduction of social distancing measures.", | |
| "numerical_results": [ | |
| { | |
| "outcome_name": "City mobility (Citymapper Mobility Index)", | |
| "value": "-23", | |
| "unit": "percentage-point change in mobility", | |
| "effect_size": "regression coefficient for social distancing measures", | |
| "confidence_interval": { | |
| "lower": "-27", | |
| "upper": "-20", | |
| "level": "95" | |
| }, | |
| "p_value": "not stated", | |
| "statistical_significance": 1, | |
| "direction": "negative" | |
| } | |
| ] | |
| }, | |
| "metadata": { | |
| "original_paper_id": "10.1101/2020.03.30.20048090", | |
| "original_paper_title": "COVID-19 related social distancing measures and reduction in city mobility", | |
| "original_paper_code": "not stated", | |
| "original_paper_data": "not stated" | |
| } | |
| } | |
| } |