About

Welcome to the data repository of The University of Maryland Social Data Science Center Global COVID-19 Trends and Impact Survey, in partnership with Facebook.

Access to the Microdata

Access to non-aggregated microdata can be granted to academic and nonprofit researchers. A request needs to be approved by UMD and Facebook and the researcher's institution must sign a Data User Agreement before data access is provided. To learn more about the requirements, eligibility, and to request access please go to COVID-19 Symptom Survey – Request for Data Access.

FAQ

1. What is the difference between Part-A and Full files?
The primary difference is the weights, based on differing inclusion criteria. A respondent is considered a Part A complete if they have responded:
  • Yes to the two consent questions (intro1 and intro2)
  • Yes to A1 (they are over 18)
  • Provided a response to country/region (A2 or A2_2)
  • And has at least one answer (yes or no) on B1 (symptoms)
A respondent is considered a full complete if they have responded:
  • Yes to the two consent questions (intro1 and intro2)
  • Yes to A1 (they are over 18)
  • Provided a response to country/region (A2 or A2_2)
  • Provided a response to two additional items

Note: these two items could include B1. Any response that qualifies for Part A complete should also qualify for full complete if they answer one additional question beyond B1, however, the two additional questions could also not include B1. Because of this, the full file is not fully nested inside the Part A file. Unless you are solely analyzing the symptom item (B1) you will likely use the full file.

2. Is there a codebook for different columns in the microdata file?
We updated a combined codebook for microdata from all waves here: combined codebook
Yes:
  • For microdata before 2020-06-27: codebook
  • For microdata after 2020-06-27: codebook
  • For microdata after 2020-11-23: codebook
  • For microdata after 2020-12-21: codebook
  • For microdata after 2021-01-14: codebook
  • For microdata after 2021-02-06: codebook
  • For microdata after 2021-03-02: codebook
  • For microdata after 2021-05-20: codebook
  • For microdata after 2021-07-23: codebook
  • For microdata (wave 12 pretest only) after 2021-10-07: wave 12 pretest codebook
    • Lookup table for survey country and region code (Beta):
  • Lookup table of country region code and names : Country region lookup table
  • Shapefile with country region code : Shapefile
  • README for the shape alignment process : README

    • Release Notes

  • 2022-05-31: Meta has developed a User Guide for the CTIS Weights (updated May 2022). This manual explains the weight methodology, gives examples of how to use the weights when calculating estimates, and states the known limitations of the weights.

  • 2021-06-03: A new version of the survey (V11) was launched on 05/20/2021. This was a major revision of the survey, and as a result of these revisions, we have observed discontinuities in our covid (COVID-like illness) and flu (influenza-like illness) aggregate indicators that are reported in our API. A country regional code table is now available for version 11. For the complete table see Country Region Response Map v11

    To test the effects of the changes to the survey, 20% of respondents have been receiving the old version of the survey (V10) and 80% have been receiving the new version of the survey (V11) since its launch on 05/20/2021. To enable monitoring of the observed discontinuities in the existing covid and flu aggregate indicators, we will be adding two new aggregate indicators to the API,which are calculated using the same methodology. These new indicators (cli and ili) will be calculated using the 80% of respondents receiving V11 while the existing indicators (covid and flu) will be changed to be calculated using only the 20% of respondents receiving V10. The new and existing indicators will be backfilled to 05/20/2021 and will continue to be reported in this manner until at least 06/17/21.

    We are continuing analyses of these discontinuities, but in the interim, we encourage users of the aggregate data to re-pull the backfilled “covid” and “flu”indicators when they become available. To be notified when they are ready, please subscribe to our survey listserv. We encourage both users of the aggregate data as well as microdata users to use caution for comparing data collected after 05/20/2021 to data collected before 05/20/2021 for other indicators as well. We also encourage microdata users to use data from the 20% of the respondents who have been receiving the old version of the survey (V10) to evaluate the effects of the survey revisions for the survey questions used in their analyses.

  • 2021-05-20: A new version of the survey(V11) has been launched. Microdata starting from 2021-05-20 will have responses from additional questions. Please see the new codebook and change summary for more information.

  • 2021-03-02: A new version of the survey(V10) has been launched. Microdata starting from 2021-03-02 will have responses from additional questions. Please see the new codebook link above.

  • 2021-02-12: Due to a survey logic issue in the version 5 survey configuration, there are about 38 miscoded B8 values each day in both Part-A and Full weighted datasets from June 27 to November 22, 2020. As of February 12, 2021, we have implemented a fix and backfilled the data. Re-downloading the data will correct the issue. The issue can also be fixed by recoding B8 as -99 if B7 is 2.

  • 2021-02-06: A new version of the survey(V9) has been launched. Microdata starting from 2021-02-06 will have responses from additional questions. Please see the new codebook link above.
    • A country regional code table is now available for version 9. For the complete table see Country Region Response Map.

  • 2021-01-26: The COVID-19 vaccine questions 'V1' and 'V2' are fielding in 5 more countries. These are the United Arab Emirates, Seychelles, Bahrain, Singapore, and Onam. Please find an updated list of countries with secured COVID-19 vaccines here. This list can also be found in the codebook for version 8.

  • 2021-01-14: A new version of the survey(V8) has been launched. Microdata starting from 2021-01-14 will have responses from additional questions. Please see the new codebook link above.
    • A country regional code table is now available for version 8. For the complete table see Country Region Response Map.

  • 2021-01-11:
    • Issue 1
    Due to a data processing issue in our pipelines, responses to questions A1, B8, C2, C3, C4, C5, C6, D3, D4, E3, and E4 were incorrectly coded in the microdata from November 23 to December 30, 2020. This issue affected both the Part A and Full weighted data sets.
    If you downloaded microdata prior to December 30 for any part of this time period, you will need to re-download the data. As of December 30, we have implemented a fix and backfilled the data, so re-downloading the data at present will correct the issue. Any analyses conducted using the errant data for the above items will need to be re-run.

    Issue 2
    We have also corrected a more minor issue which does not affect data integrity for survey responses at the individual response level, but may have affected data aggregation. In Wave 7, some region names were formatted slightly differently than in previous waves and were missing the GID1 field. We expect that this would only have caused issues for region-level aggregations during the period during which Wave 6 and Wave 7 overlapped (December 21 to December 28, 2020), or if you are explicitly using the GID1 field. We expect to land a fix and backfill data to correct this issue by January 12, 2021; we will post in the release notes on the microdata API when this fix is fully implemented. At that time, re-downloading the data will correct any issues with region names or GID1.

  • 2020-12-21: A new version of the survey(V7) has been launched. Microdata starting from 2020-12-21 will have responses from additional questions. Please see the new codebook link above.
    • A country regional code table is now available for version 7. For the complete table see Country Region Response Map.
    Seen but unanswered questions are now set to -77.
    Missing, valid skipped, and invalid answers are set to -99.

  • 2020-12-08: There was an overlap between wave 5 and wave 6b of the survey. Data for questions B13_* and B14_* was collected on 11-30-2020. We will collect this additional data for December on 12-10-2020. Moving forward it will be collected on the 1st of each month.
    • From 11-23-2020 to 12-4-2020 the survey version '5' identifier was not added to the datasets, it was left blank. This is now fixed.

  • 2020-12-03: Column names of microdata files from 11-23-2020 to 11-30-2020 have been coded correctly to match the codebook. C7.1 is now C14. B1b_x14 was added.

  • 2020-11-20: A new version of the survey(V6b) has been launched. Microdata starting from 2020-11-23 will have responses from additional questions. Please see the new codebook link above.
    • A country regional code table is now available. For the complete table see Country Region Response Map.

  • 2020-09-30: The microdata has been updated to include unweighted countries. Column '1w_0unw' has been added to the csv files to flag weighted and unweighted countries. For the list of weighted countries see Weighted Countries List. For the Weights and Methodology Brief for the COVID-19 Symptom Survey please follow this link: Weights and Methodology.

  • 2020-06-27: A new version of the survey(V5) has been launched. Microdata starting from 2020-06-27 will have responses from additional questions.