A survey tool collects responses. An EDC manages a record: who entered what, what changed, who questioned it, who signed it and when it was frozen. This page explains the five differences, when a survey is the right tool, and where the line sits.
Free sandbox · No credit card · 21 CFR Part 11 aligned
| Survey tool | EDC | |
|---|---|---|
| Anonymous or one-off responses | ||
| Participant-level longitudinal record | ||
| Field-level audit trail with reason for change | ||
| Edit checks across fields and visits | ||
| Query between monitor and site | ||
| E-signature on a completed record | ||
| Lock a form or dataset against change |
The short answer
Two different jobs
Survey software is built to reach many people, collect answers quickly and summarise them. Its design centre is the respondent: easy forms, distribution links, branching, charts. Many survey tools are excellent at that, and some offer security and privacy features suited to research. The HIPAA question for survey tools has its own page: HIPAA compliant survey tools for research.
An EDC (electronic data capture system) is built to hold the case report form record for a defined set of participants across visits. Its design centre is the record: every value is attributable to a person and a time, every change is explained, discrepancies are raised and resolved, and the dataset can be frozen and exported with its definition. The difference shows up when someone asks a hard question months later.
Resting heart rate
HRBelow expected range 35 to 150. Query raised to site.
Reason for change
Recorded in the audit trail with user and time
Corrected from source: 59The five controls
These are the capabilities a trial record relies on. For each, the question is not whether a survey tool could imitate it with effort, but whether it is built in, enforced and evidenced.
A survey tool records that a response arrived. A trial needs every change after that: old value, new value, who, when and why. In Capture the audit trail is field-level and captures timestamp, user identity, old value, new value and reason for change. In a typical survey tool, an edit to a submitted response either is not possible or leaves no explanation.
Survey validation usually checks a single question: required, numeric, in range. Edit checks in an EDC compare values across fields and visits and set priority. In Capture, a value that breaks a rule raises an auto-query when the site enters it. Derived fields such as BMI or eGFR are calculated and shown read-only, so people do not type them by hand.
A discrepancy needs a conversation that is part of the record: the monitor or data manager asks, the site answers or corrects, and the query is closed. Query management links all of that to the field. In a survey tool this happens in email, and the link between the question and the change is lost.
An investigator attests that data are accurate. Electronic signatures need to be tied to the individual, show the meaning of the signature and be bound to the signed content. See electronic signatures for clinical trials. A survey tool's submit button is not a signature of this kind.
Forms in an EDC move through draft and approved states, and approved forms are locked for live use, so the form that collected the data is the form you can show. At the end, data are frozen for analysis. See database lock. Exports carry a data dictionary, and Capture can export SDTM datasets as SAS XPT with Define-XML (CDISC SDTM export). Survey exports are typically a flat file of responses with question text as headers.
Where the line sits
A rule of thumb: ask what would happen if one value were wrong and nobody could show how it got there.
| Use case | Survey tool | EDC | Notes |
|---|---|---|---|
| Recruitment interest form or screening questionnaire before consent | Fine | Optional | Collect the minimum. Do not treat it as trial data. |
| Anonymous opinion survey of clinicians or participants | Fine | Overkill | No linking to a participant record is needed. |
| Pilot of an instrument in a non-regulated study | Often fine | Better if reused | Check your ethics approval and data protection terms. |
| Participant-reported outcomes in an interventional study | Risky | Preferred | Needs a participant-level record and time stamps. See ePRO. |
| Case report forms completed by site staff | Not suitable | Required in practice | Queries, source verification and signatures apply. |
| Data supporting a regulatory submission | Not suitable | Required in practice | Expect inspection of controls and validation. |
Named survey products vary in features. Check any tool's own documentation and your ethics and regulatory advice.
Rebuild your survey as an eCRF or ePRO in the free Capture sandbox, enter a bad value and watch the query and audit trail appear. Free, every feature, no credit card.
Moving from a survey to an EDC
Where Capture fits
Capture is an all-in-one clinical trial platform: EDC, eCRF builder, ePRO/eCOA, eConsent and randomization with one audit trail. You build forms from ten question types, or let the AI study builder draft forms from a protocol or an uploaded file, and review them before anything is saved. Participants complete ePRO on their phone; sites complete eCRFs. All of it ends up in the same governed record.
Evening diary
Question 3 of 8
How would you rate your fatigue today?
0 = no fatigue, 10 = worst imaginable
Objections
Because the cost of the wrong tool arrives late. A study that begins in a survey tool and later needs an audit trail has to migrate mid-flight, rebuild forms and reconcile responses. That is more expensive than starting in an EDC, particularly when the sandbox is free. Teams on Google Forms or similar face the same migration; see how to migrate from Google Forms and Sheets and Google Forms for clinical research.
Keep the survey tool for what it does well: interest forms, feedback, anonymous polls. Put the trial record in a system built to hold it. See the eCRF builder for what that looks like in practice.
A survey tool collects and summarises responses. An EDC manages a participant-level trial record with an audit trail, edit checks, queries, electronic signatures and data locking, so every value can be attributed, questioned and explained.
For recruitment interest, anonymous feedback and some non-regulated research, yes. For case report forms or data that supports a regulatory decision, a survey tool normally lacks the controls required. Check with your ethics committee, sponsor and regulatory advisers.
They are built as survey platforms. Some offer privacy and security features useful in research, but an EDC role requires the five controls described here, and validation for that purpose. See the individual comparison pages for details.
It shows who changed which value, when and why. Without it you cannot demonstrate that the final dataset reflects the source, which undermines the reliability of results.
A query is a question about a data value, raised by a monitor, data manager or an automatic edit check, answered by the site and closed. It stays attached to the field, so the history of the discrepancy is preserved.
ePRO collects participant-reported outcomes inside a trial record, with timestamps, schedules, reminders and audit trail. A survey link collects a response without that surrounding record.
You can import or re-enter historical data, but data not collected under the EDC's controls should be labelled and handled as such. Decide with your data manager what is migrated and what stays as an archive.
Keep exploring
HIPAA compliant survey tools for research
The privacy lens on survey tools.
Qualtrics compared with Capture
Named comparison.
SurveyMonkey compared with Capture
Named comparison.
Jotform compared with Capture
Named comparison.
Edit checks software
How cross-field checks work.
Query management software
How discrepancies are resolved.
Free sandbox with every feature. No credit card, and you pay only when you go live with real participants.