Data dictionary
What's in each part of the v-safe release, as OpenVSafe shows it. Every part links to a person by their CDC registrant code. See the V-safe FAQ for where the data came from and how it's counted.
Registrants 10,147,001 people
One row per person who signed up, registered from 13 December 2020 to 19 May 2023.
| Field | What it means |
|---|---|
| Registrant code | The CDC's pseudonym for the person, like ABC-12345-67890. The same code appears in every other part. |
| Sex | As entered at registration. |
| Zip3 and state | The first three digits of the zip code; the state is worked out from them. |
| Registered | Date of sign-up. |
| Relationship | Blank when people registered themselves. Otherwise "Child or adolescent in my care" (184,591), "Adult relative or friend" (28,343) or "Other". |
| Guardian | For someone registered by another person, the registrant code of the person who registered them. |
| Race and ethnicity | From a separate file; a person can have more than one. |
Vaccinations 21,066,361 doses
One row per COVID-19 vaccine dose a person recorded in v-safe.
| Field | What it means |
|---|---|
| Manufacturer | Pfizer-BioNTech (11.0 million), Moderna (9.5 million), Janssen/Johnson & Johnson (537,000), Novavax, or other/unknown. |
| Dose number | 1, 2, 3 and so on, as recorded. |
| Vaccination date | The date of the dose. |
| Age band | The person's age at that dose, in the CDC's bands (16–20, 21–25 and so on). Exact ages aren't released. |
| Given with | Whether another vaccine was given at the same visit, and which. |
Health check-ins 151,847,152 check-ins · 9,609,282 people
One row per completed survey, from 14 December 2020 to 30 June 2023. Each dose started its own schedule of surveys.
| Field | What it means |
|---|---|
| Survey | Which dose, and when: day 0 (the day of the dose), daily for days 1–6, weekly from day 7 to day 42, then 3, 6 and 12 months. Children under 3 had their own version (265,347 check-ins). |
| Date | The date the survey was started. |
| Symptoms | Check boxes, each with a severity: at the injection site (pain, redness, swelling, itching) and in the body (fatigue, headache, fever, chills, joint pain, muscle or body aches, nausea, vomiting, diarrhea, abdominal pain, rash, swollen glands). Surveys for children also asked about irritability, sleepiness and loss of appetite. |
| Temperature | If the person took it. |
| Feeling today | How the person felt that day. |
| Health impact | Whether symptoms stopped them working, going to school or doing normal activities. |
| Medical care | Whether they got care: telehealth, a clinic, an emergency room or a hospital stay. Answering yes could lead to a call from the call center. |
| Health now | On the later surveys: health now compared with before vaccination, and whether the person thought the vaccine might be the cause. |
| Pregnancy | Whether the person was pregnant, or had a positive pregnancy test. |
| Tested positive | Whether they had tested positive for COVID-19, and when. |
Free text 7,554,929 entries
What people typed in the surveys' "other" boxes, released in twelve monthly batches from February 2024 to January 2025. Entries have no date, so they can't be tied to a particular check-in.
| Field | What it means |
|---|---|
| Symptoms description | Free description of symptoms or health problems. |
| Systemic reaction (other) | Other symptoms in the body, beyond the check boxes. |
| Healthcare visit (other) | Other kinds of medical care. |
| Redacted | Words blacked out by the CDC under FOIA exemption (b)(6). 12,543 entries have a redaction. |
| Release | Which of the twelve batches the entry came from. |
MedDRA codes 30,987,860 codes · 10,737 terms
The CDC coded the free text into MedDRA, the standard dictionary of medical terms used by drug regulators. There are three coding releases; each recodes the text, so the same entry can appear in all three.
| Field | What it means |
|---|---|
| Release | 2021-09 (2.7 million people), 2023-04 (2.6 million) or 2024-11 (3.5 million). The site ranks terms by 2024-11, the newest. |
| Field coded | Which free-text box the code came from: symptoms description (SD), systemic reaction other (SRO) or healthcare visit other (HCVO). |
| Preferred term | The MedDRA term for the condition, for example "Tinnitus" or "Pericarditis". This is what the site searches and counts. |
| Lowest-level term | The closer-to-the-words MedDRA term the preferred term was chosen from. |
| Date and survey | The check-in the coded text came from. Unlike the free text itself, codes are dated. |
| Active | Whether the CDC kept the code. A person's page marks inactive codes with ○, and they aren't counted. |
Call center 1,605,019 cases · 1,127,849 people
When someone reported getting medical care, a report went to the v-safe call center, which opened a case and tried to phone them. Cases run from 14 December 2020 to 15 June 2023; reports end on 22 May 2023.
| Field | What it means |
|---|---|
| Report | What triggered the call: the survey, dose, days since vaccination, the health impact and the kind of medical care (telehealth, outpatient, emergency, hospital). |
| Case | The call center's record: reported date, final outcome (successful, unsuccessful and so on), success date, and any updated vaccine or pregnancy details. |
| Call attempts | Each attempt to reach the person, with its date and result. |
| Outcomes | What the call led to, for example whether a VAERS report was filed. A case can have several. |
Pregnancy registry survey 79,265 responses
A one-time survey, answered from 13 April to 7 June 2021, about pregnancy and whether the person could be contacted for the CDC's v-safe pregnancy registry.
| Field | What it means |
|---|---|
| Pregnancy status | Pregnant at the time of vaccination, pregnant after vaccination, or not pregnant at or since vaccination. |
| Contact | Whether the person agreed to be contacted for the registry, and when suited them. |
| Date | When they answered. |
VAERS matches 40,242 VAERS reports · 27,736 people matched
VAERS reports marked as coming from v-safe, and OpenVSafe's matches between them and v-safe call center cases. The release doesn't link the two; we matched them, as explained in the V-safe FAQ.
| Field | What it means |
|---|---|
| VAERS ID | The public VAERS report number; it links to the report on OpenVAERS. |
| Score | Out of 11: timing, dose and shared symptoms. The next-best report's score is shown too. |
| Confidence | High (8+ and 3 ahead of the next best) or medium (5+ and 2 ahead). People counted above have a high or medium match. |
| Shared symptoms | How many of the VAERS report's symptom terms the person also has in v-safe. |