# Contingency Tables

This documentation describes the fine-resolution contingency tables produced by grouping COVID Symptom Survey individual responses by various self-reported demographic features.

These contingency tables provide granular breakdowns of COVID-related topics such as vaccine uptake and acceptance. They are more detailed than the coarse aggregates reported in the COVIDcast Epidata API, which are grouped only by geographic region. Individual response data for the survey is available, but only to academic or nonprofit researchers who sign a Data Use Agreement, whereas these contingency tables are available to the general public.

Please see our survey credits and citation information for information on how to cite this data if you use it in a publication.

Important updates for data users, including corrections to data or updates on data processing delays, are posted as OUTAGES.txt in the directory where the data is hosted.

## Table of contents

1. Available Data
2. File Format
3. Indicators

## Available Data

We currently provide data files at several levels of geographic and temporal aggregation. The reason for this is that each file is filtered to only include estimates for a particular group if that group includes 100 or more responses. Providing several levels of granularity allows us to provide coverage for a variety of use cases. For example, users who need the most up-to-date data or are interested in time series analysis should use the weekly files, while those who want to study groups with smaller sample sizes should use the monthly files. Because monthly aggregates include more responses, they have lower missingness when grouping by several features at a time.

Files contain all time periods for a given period type-aggregation type combination.

Individual CSVs containing a single week or month for a given aggregation type are also available.

### Dates

The included files provide estimates for various metrics of interest over a period of either a full epiweek (or MMWR week, a standardized numbering of weeks throughout the year) or a full calendar month.

Note: If a survey item was introduced in the middle of an aggregation period, derived indicators will be included in aggregations for that period but will only use a partial week or month of data.

CSVs for the month of January 2021 only use data from January 6-31 due to a definitional change in a major vaccine item on January 6.

### Regions

At the moment, only nation-wide and state groupings are available.

### Privacy

The aggregates are filtered to only include estimates for a particular group if that group includes 100 or more responses. Especially in the weekly aggregates, many of the state-level groups have been filtered out due to low sample size. In such cases, files that group by a single demographic of interest will likely provide more coverage.

## File Format

### Naming

“Rollup” files containing all time periods for a given period type-aggregation type combination have names of the form:

{period_type}_{geo_type}_{aggregation_type}.csv.gz


CSVs for individual time periods have names of the form:

{period_start}_{period_end}_{period_type}_{geo_type}_{aggregation_type}.csv


Dates are in yyyyMMdd format. period_start refers to the first day of the time period survey responses were aggregated over, in the Pacific time zone (UTC - 7). Unless noted otherwise, the time period is always a complete month (period_type = monthly) or epiweek (period_type = weekly). geo_type is the geographic level responses were aggregated over. aggregation_type is a concatenated list of other grouping variables used, ordered alphabetically. Values for variables used in file naming align with those within files as specified in the column section below.

### Columns

Within a CSV, the first few columns store metadata of the aggregation:

Column Description
survey_geo Survey geography (“US”)
period_start Date of first day of time period used in aggregation
period_end Date of last day of time period used in aggregation
period_val Month or week number
geo_type Geography type (“state”, “nation”)
aggregation_type Concatenated list of grouping variables, ordered alphabetically
country Country name (“United States”)
ISO_3 Three-letter ISO country code (“USA”)
GID_0 GADM level 0 ID
state State name; “Overall” if aggregation not grouped at the state level
state_fips State FIPS code; NA if aggregation not grouped at the state level
county County name; “Overall” if aggregation not grouped at the county level
county_fips County FIPS code; NA if aggregation not grouped at the county level
issue_date Date on which estimates were generated

These are followed by the grouping variables used in the aggregation, ordered alphabetically, and the indicators. Each indicator reports four columns (unrounded):

• val_<indicator name>: the main value of interest, e.g., percent, average, or count, estimated using the survey weights to better match state demographics
• se_<indicator name>: the standard error of val_<indicator name>
• sample_size_<indicator name>: the number of survey responses used to calculate val_<indicator name>
• represented_<indicator name>: the number of people in the population that val_<indicator name> represents over all days in the given time period. This is the sum of survey weights for all survey responses used.

All aggregates using the same set of grouping variables appear in a single CSV.

### Missing Values

Grouping variables (including region) will be missing (NA) to represent respondents who provided one or more responses to survey items used for indicators (e.g., vaccine uptake) but who did not provide a response to the survey item used for the particular grouping variable. For example, if grouping by gender, we would report the groups: male, female, other, and NA, respondents who did not provide a response to the gender question.

For a given respondent group (25-34 year old healthcare workers in Nebraska, e.g.) sample size can vary by indicator because of the survey display logic. For example, all respondents are asked if they have received a COVID-19 vaccination (item V1), but only those who say they have are asked how many doses they have received (item V2). This means that the sample size for V2 is smaller than that for V1. Because indicators are censored individually, it is possible that V1-derived indicators will be reported for a given group while V2-derived indicators are not. In this case, the V2-derived indicator columns will be marked as missing (NA) for that group.

## Indicators

The files contain weighted estimates of the percent of respondents who fulfill one or several criteria. Estimates are broken out by state, age, gender, race, ethnicity, occupation, and health conditions.

Indicators beginning “hesitant_” (not listed) are variants of other described indicators calculated among respondents who say they would “probably not” or “definitely not” choose to get vaccinated, if offered today (item V3/V3a). Note: Until Wave 11 (May 19, 2021), this item was asked of everyone who indicated that they had not received a COVID-19 vaccine; after that date, this item was only asked of people who indicated that they had not received a COVID-19 vaccine and did not have an appointment to do so.

Indicators beginning “defno_” (not listed) are variants of other described indicators calculated among respondents who say they would “definitely not” choose to get vaccinated, if offered today.

We plan to expand this list of indicators based on research needs; if you have a public health or research need for a particular variable not listed here, please contact us at delphi-survey-info@lists.andrew.cmu.edu.

### Symptoms

Indicator Description Survey Item
pct_cli Estimated percentage of people with COVID-like illness, using the same definition as in the API.
Earliest date available: 2021-01-01
A1 and A2
pct_ili Estimated percentage of people with influenza-like illness, using the same definition as in the API.
Earliest date available: 2021-01-01
A1 and A2
pct_hh_cmnty_cli Estimated percentage of people reporting illness in their local community, including their household, using the same definition as in the API.
Earliest date available: 2021-01-01
A1, A2, and A4
pct_anosmia Estimated percentage of people experiencing loss of smell or taste in the last 24 hours.
Earliest date available: 2021-01-01
A2

### Behavior

Indicator Description Survey Item
pct_wearing_mask_7d Estimated percentage of people who wore a mask for most or all of the time while in public in the past 7 days; those not in public in the past 7 days are not counted.
Earliest date available: 2021-02-08
C14a
pct_wearing_mask_5d Discontinued as of Wave 8, Feb 8, 2021 Estimated percentage of people who wore a mask for most or all of the time while in public in the past 5 days; those not in public in the past 5 days are not counted.
Earliest date available: 2021-01-01
C14
pct_direct_contact Discontinued as of Wave 11, May 19, 2021 Estimated percentage of people who in the past 24 hours had a non-physical interaction (like conversing) for more than 5 minutes at a distance of 6 feet or less or a physical interaction (like hand-shaking, hugging, or kissing) with anyone outside their household.
Earliest date available: 2021-01-01
C10

### Vaccine Uptake and Acceptance

Indicator Description Survey Item
pct_vaccinated Estimated percentage of respondents who have already received a COVID vaccine.
Earliest date available: 2021-01-01
V1
pct_received_2_vaccine_doses Estimated percentage of respondents who have received two doses of a COVID-19 vaccine, among respondents who have received either one or two doses of a COVID-19 vaccine.
Earliest date available: 2021-01-01
V2
pct_vaccinated_appointment_or_accept Estimated percentage of respondents who either have already received a COVID vaccine or have an appointment to get a COVID vaccine or would definitely or probably choose to get vaccinated, if a vaccine were offered to them today.
Earliest date available: 2021-05-19
V1, V11a, V3a
pct_vaccinated_or_accept Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who either have already received a COVID-19 vaccine or would definitely or probably choose to get vaccinated, if a vaccine were offered to them today.
Earliest date available: 2021-01-01
V1, V3
pct_appointment_or_accept_vaccine Estimated percentage of respondents who either have an appointment to get a COVID-19 vaccine or would definitely or probably choose to get vaccinated, if a vaccine were offered to them today, among respondents who have not yet been vaccinated.
Earliest date available: 2021-05-19
V11a, V3a
pct_accept_vaccine_no_appointment Estimated percentage of respondents who would definitely or probably choose to get vaccinated, if a vaccine were offered to them today, among respondents who have not yet been vaccinated and do not have an appointment to do so.
Earliest date available: 2021-05-19
V3a
pct_accept_vaccine Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who would definitely or probably choose to get vaccinated, if a vaccine were offered to them today, among respondents who have not yet been vaccinated.
Earliest date available: 2021-01-01
V3
pct_hesitant_vaccine Estimated percentage of respondents who would definitely not or probably not choose to get vaccinated, if a vaccine were offered to them today, among respondents who have not yet been vaccinated. Note: Until Wave 11 (May 19, 2021), this item was asked of everyone who indicated that they had not received a COVID-19 vaccine; after that date, this item was only asked of people who indicated that they had not received a COVID-19 vaccine and did not have an appointment to do so.
Earliest date available: 2021-01-01
V3 or V3a
pct_accept_vaccine_no_appointment_defyes Estimated percentage of respondents who would definitely choose to get vaccinated, if a vaccine were offered to them today, among respondents who have not yet been vaccinated and do not have an appointment to do so.
Earliest date available: 2021-05-19
V3a
pct_accept_vaccine_no_appointment_probyes Estimated percentage of respondents who would probably choose to get vaccinated, if a vaccine were offered to them today, among respondents who have not yet been vaccinated and do not have an appointment to do so.
Earliest date available: 2021-05-19
V3a
pct_accept_vaccine_no_appointment_probno Estimated percentage of respondents who would probably not choose to get vaccinated, if a vaccine were offered to them today, among respondents who have not yet been vaccinated and do not have an appointment to do so.
Earliest date available: 2021-05-19
V3a
pct_accept_vaccine_no_appointment_defno Estimated percentage of respondents who would definitely not choose to get vaccinated, if a vaccine were offered to them today, among respondents who have not yet been vaccinated and do not have an appointment to do so.
Earliest date available: 2021-05-19
V3a
pct_accept_vaccine_defyes Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who would definitely choose to get vaccinated, if a vaccine were offered to them today, among respondents who have not yet been vaccinated.
Earliest date available: 2021-01-01
V3
pct_accept_vaccine_probyes Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who would probably choose to get vaccinated, if a vaccine were offered to them today, among respondents who have not yet been vaccinated.
Earliest date available: 2021-01-01
V3
pct_accept_vaccine_probno Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who would probably not choose to get vaccinated, if a vaccine were offered to them today, among respondents who have not yet been vaccinated.
Earliest date available: 2021-01-01
V3
pct_accept_vaccine_defno Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who would definitely not choose to get vaccinated, if a vaccine were offered to them today, among respondents who have not yet been vaccinated.
Earliest date available: 2021-01-01
V3
pct_informed_access Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who are very or moderately informed about how to get a COVID-19 vaccination.
Earliest date available: 2021-02-08
V13
pct_appointment_not_vaccinated Estimated percentage of respondents who have an appointment to get a COVID-19 vaccine, among respondents who have not yet been vaccinated.
Earliest date available: 2021-05-19
V11a
pct_appointment_have Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who have an appointment to get a COVID-19 vaccine, among respondents who answered “Yes, definitely” or “Yes, probably” when asked if they would get vaccinated if offered.
Earliest date available: 2021-03-02
V11
pct_vaccine_tried Estimated percentage of respondents who have tried to get a COVID-19 vaccine, among respondents who answered “Yes, definitely” or “Yes, probably” when asked if they would get vaccinated if offered.
Earliest date available: 2021-05-19
V12a
pct_appointment_tried Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who have tried to make an appointment to get a COVID-19 vaccine, among respondents who answered “Yes, definitely” or “Yes, probably” when asked if they would get vaccinated if offered.
Earliest date available: 2021-03-02
V12

### Outreach and Image

Indicator Description Survey Item
pct_trust_covid_info_doctors Estimated percentage of respondents who trust doctors and other health professionals they go to for medical care to provide accurate news and information about COVID-19.
Earliest date available: 2021-05-19
I6
pct_trust_covid_info_experts Estimated percentage of respondents who trust scientists and other health experts to provide accurate news and information about COVID-19.
Earliest date available: 2021-05-19
I6
pct_trust_covid_info_cdc Estimated percentage of respondents who trust the CDC to provide accurate news and information about COVID-19.
Earliest date available: 2021-05-19
I6
pct_trust_covid_info_govt_health Estimated percentage of respondents who trust government health officials to provide accurate news and information about COVID-19.
Earliest date available: 2021-05-19
I6
pct_trust_covid_info_politicians Estimated percentage of respondents who trust politicians to provide accurate news and information about COVID-19.
Earliest date available: 2021-05-19
I6
pct_trust_covid_info_journalists Estimated percentage of respondents who trust journalists to provide accurate news and information about COVID-19.
Earliest date available: 2021-05-19
I6
pct_trust_covid_info_friends Estimated percentage of respondents who trust friends and family to provide accurate news and information about COVID-19.
Earliest date available: 2021-05-19
I6
pct_trust_covid_info_religious Estimated percentage of respondents who trust religious leaders to provide accurate news and information about COVID-19.
Earliest date available: 2021-05-19
I6
pct_vaccine_likely_friends (formerly pct_trust_fam) Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who would be more likely to get a COVID-19 vaccine if it were recommended to them by friends and family, among respondents who have not yet been vaccinated.
Earliest date available: 2021-01-01
V4
pct_vaccine_likely_who (formerly pct_trust_who) Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who would be more likely to get a COVID-19 vaccine if it were recommended to them by the World Health Organization, among respondents who have not yet been vaccinated.
Earliest date available: 2021-01-01
V4
pct_vaccine_likely_govt_health (formerly pct_trust_govt) Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who would be more likely to get a COVID-19 vaccine if it were recommended to them by government health officials, among respondents who have not yet been vaccinated.
Earliest date available: 2021-01-01
V4
pct_vaccine_likely_politicians (formerly pct_trust_politicians) Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who would be more likely to get a COVID-19 vaccine if it were recommended to them by politicians, among respondents who have not yet been vaccinated.
Earliest date available: 2021-01-01
V4
pct_vaccine_likely_doctors Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who would be more likely to get a COVID-19 vaccine if it were recommended to them by doctors and other health professionals they go to for medical care, among respondents who have not yet been vaccinated. This item was shown to respondents starting in Wave 8.
Earliest date available: 2021-02-08
V4
pct_vaccine_likely_local_health (formerly pct_trust_healthcare) Discontinued as of Wave 8, Feb 8, 2021 Estimated percentage of respondents who would be more likely to get a COVID-19 vaccine if it were recommended to them by local health workers, among respondents who have not yet been vaccinated.
Earliest date available: 2021-01-01
V4

### Reasons for Hesitancy

The set of “barrier” items correspond to the set of “hesitancy_reasons” items in the API.

Indicator Description Survey Item
pct_worried_vaccine_sideeffects (formerly pct_concerned_sideeffects) Estimated percentage of respondents who are very or moderately concerned that they would “experience a side effect from a COVID-19 vaccination.” Note: Until March 2, 2021, all respondents answered this question, including those who had already received one or more doses of a COVID-19 vaccine; beginning on that date, only respondents who said they have not received a COVID vaccine are asked this question.
Earliest date available: 2021-01-01
V9
pct_barrier_sideeffects Estimated percentage of respondents who say they are hesitant to get vaccinated because they are worried about side effects, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered.
Earliest date available: 2021-02-08
V5abc
pct_barrier_allergic Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who say they are hesitant to get vaccinated because they are worried about having an allergic reaction, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered.
Earliest date available: 2021-02-08
V5abc
pct_barrier_ineffective Estimated percentage of respondents who say they are hesitant to get vaccinated because they don’t know if a COVID-19 vaccine will work, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered.
Earliest date available: 2021-02-08
V5abc
pct_barrier_dontneed Estimated percentage of respondents who say they are hesitant to get vaccinated because they don’t believe they need a COVID-19 vaccine, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered.
Earliest date available: 2021-02-08
V5abc
pct_barrier_dislike_vaccines Estimated percentage of respondents who say they are hesitant to get vaccinated because they dislike vaccines, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered.
Earliest date available: 2021-02-08
V5abc
pct_barrier_not_recommended Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who say they are hesitant to get vaccinated because their doctor did not recommend it, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered.
Earliest date available: 2021-02-08
V5abc
pct_barrier_wait_safety Estimated percentage of respondents who say they are hesitant to get vaccinated because they want to wait to see if the COVID-19 vaccines are safe, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered.
Earliest date available: 2021-02-08
V5abc
pct_barrier_low_priority Estimated percentage of respondents who say they are hesitant to get vaccinated because they think other people need it more than they do, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered.
Earliest date available: 2021-02-08
V5abc
pct_barrier_cost Estimated percentage of respondents who say they are hesitant to get vaccinated because they are worried about the cost, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered. This series of items was shown to respondents starting in Wave 8.
Earliest date available: 2021-02-08
V5abc
pct_barrier_distrust_vaccines Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who say they are hesitant to get vaccinated because they don’t trust COVID-19 vaccines, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered.
Earliest date available: 2021-02-08
V5abc
pct_barrier_distrust_govt Estimated percentage of respondents who say they are hesitant to get vaccinated because they don’t trust the government, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered.
Earliest date available: 2021-02-08
V5abc
pct_barrier_health_condition Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who say they are hesitant to get vaccinated because they have a health condition that may impact the safety of a COVID-19 vaccine, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered.
Earliest date available: 2021-02-08
V5abc
pct_barrier_pregnant Discontinued as of Wave 11, May 19, 2021 Estimated percentage of respondents who say they are hesitant to get vaccinated because they are currently, or are planning to be, pregnant or breastfeeding, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered.
Earliest date available: 2021-02-08
V5abc
pct_barrier_religious Estimated percentage of respondents who say they are hesitant to get vaccinated because it is against their religious beliefs, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered.
Earliest date available: 2021-02-08
V5abc
pct_barrier_other Estimated percentage of respondents who say they are hesitant to get vaccinated for another reason, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered.
Earliest date available: 2021-02-08
V5abc

### Reasons for Believing Vaccine is Unnecessary

Respondents who indicate that “I don’t believe I need a COVID-19 vaccine” (in items V5a, V5b, V5c, or, prior to Wave 11, V5d) are asked a follow-up item asking why they don’t believe they need the vaccine. These signals summarize the reasons selected. Respondents who do not select any reason (including “Other”) are treated as missing.

This item was shown to respondents starting in Wave 8.

Indicator Description Survey Item
pct_dontneed_reason_had_covid Estimated percentage of respondents who say they don’t need to get a COVID-19 vaccine because they already had the illness, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered and provided at least one reason for why they believe a COVID-19 vaccine is unnecessary.
Earliest date available: 2021-02-08
V6 and V5bc
pct_dontneed_reason_dont_spend_time Estimated percentage of respondents who say they don’t need to get a COVID-19 vaccine because they don’t spend time with high-risk people, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered and provided at least one reason for why they believe a COVID-19 vaccine is unnecessary.
Earliest date available: 2021-02-08
V6 and V5bc
pct_dontneed_reason_not_high_risk Estimated percentage of respondents who say they don’t need to get a COVID-19 vaccine because they are not in a high-risk group, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered and provided at least one reason for why they believe a COVID-19 vaccine is unnecessary.
Earliest date available: 2021-02-08
V6 and V5bc
pct_dontneed_reason_precautions Estimated percentage of respondents who say they don’t need to get a COVID-19 vaccine because they will use other precautions, such as a mask, instead, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered and provided at least one reason for why they believe a COVID-19 vaccine is unnecessary.
Earliest date available: 2021-02-08
V6 and V5bc
pct_dontneed_reason_not_serious Estimated percentage of respondents who say they don’t need to get a COVID-19 vaccine because they don’t believe COVID-19 is a serious illness, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered and provided at least one reason for why they believe a COVID-19 vaccine is unnecessary.
Earliest date available: 2021-02-08
V6 and V5bc
pct_dontneed_reason_not_beneficial Estimated percentage of respondents who say they don’t need to get a COVID-19 vaccine because they don’t think vaccines are beneficial, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered and provided at least one reason for why they believe a COVID-19 vaccine is unnecessary.
Earliest date available: 2021-02-08
V6 and V5bc
pct_dontneed_reason_other Estimated percentage of respondents who say they don’t need to get a COVID-19 vaccine for another reason, among respondents who answered “Yes, probably”, “No, probably not”, or “No, definitely not” when asked if they would get vaccinated if offered and provided at least one reason for why they believe a COVID-19 vaccine is unnecessary.
Earliest date available: 2021-02-08
V6 and V5bc