DOI: 10.3886/icpsr39206.v1
title: COVID-19 Trends and Impact Survey (CTIS), Global, 2020-2022
title: Version 1

description: The COVID-19 Trends and Impact Survey (CTIS) was conducted by the Delphi Group at Carnegie Mellon University (CMU) in the United States (US) and by the University of Maryland (UMD) Social Data Science Center (SoDa) globally, in partnership with Meta. CTIS was a daily repeated cross-sectional survey that ran continuously starting April 6, 2020 in the US and starting April 23, 2020 globally. Both surveys concluded data collection on June 25, 2022. CTIS collected data in 200+ countries and territories, including 114 where Meta provided survey weights. The sampling frame was Facebook users aged 18 years or older who have been active on the platform in the last month. Sampled Facebook users saw the invitation at the top of their Feed, but the surveys were collected by the universities using Qualtrics. Meta neither collected nor received survey responses. The sample was stratified by subnational regions. Respondents were sampled as frequently as every month and as infrequently as every six months, depending on the population density of the subnational region in which they lived. Due to the minimum sampling frequency, pooled analyses should not combine more than a month of data. There were 12 versions of the survey questionnaires. The Delphi US CTIS was translated into 8 languages. The UMD Global CTIS was translated into 66 languages.
This collection is comprised of three categories of data:
a. Individual-level microdata files, which will be available to eligible academic and nonprofit researchers with fully executed Data Use Agreements (DUAs). 
b. Daily aggregate estimates at the country and subnational region levels disseminated via public APIs at CMU and UMD. 
c. Weekly and monthly aggregate estimates broken out by respondent characteristics (e.g., age, gender, vaccination status) at the country and subnational administrative level-1 region-level disseminated via publicly available CSV-formatted contingency tables.
This collection currently only contains the aggregate data and associated documentation. The microdata and contingency tables are forthcoming.
description: The aim of this study was to support research and inform public health decisions relating to the COVID-19 pandemic.
description: CTIS was a daily repeated cross-sectional survey that ran continuously starting April 23, 2020 globally. Data collection concluded on June 25, 2022. CTIS collected data in
200+ countries and territories (everywhere except Cuba (CU), China (CN), Iran (IR),
North Korea (NP), Syria (SY), and Turkmenistan (TM)), including 114 where Meta provided survey
weights. The sampling frame was Facebook users aged 18 years or older who
had been active on the platform in the last month. Sampled Facebook users saw the invitation at the top of their Feed, but the
surveys were collected by the universities using Qualtrics. Meta neither
collected nor received survey responses. There were 12 versions of the survey questionnaires. The UMD Global CTIS was translated into 66
languages.
description: Please see the User Guide for the COVID-19 Trends and Impact Survey Weights for details on use of the weights.
description: The sample was stratified by subnational regions. Respondents were sampled
as frequently as every month and as infrequently as every six months,
depending on the population density of the subnational region in which they
lived. Due to the minimum sampling frequency, pooled analyses should not
combine more than a month of data.
description: Datasets: 
DS1: COVID-19 Trends and Impact Survey (CTIS), Global, 2020-2022
description: Adult residents of the sampled countries who are active Facebook users. Smallest Geographic Unit: Country
description: Please visit the CTIS Global website for additional information.