ODK and KoboToolbox are free, widely used tools for field surveys, often in low-resource settings. When the same project becomes a clinical trial, it needs an audit trail with reasons, e-signatures, visit schedules and role-based access. Capture adds those without setup fees.
Free sandbox · No credit card · 21 CFR Part 11 aligned
Tests
5
Hands-on
4
To confirm
1
Capture vs ODK / KoboToolbox: the short version
0
sales calls needed to start building
1
audit trail across EDC, ePRO, eConsent and randomization
Free
sandbox with every feature, no time limit
EU + US
hosting in Frankfurt or N. Virginia
The wedge
Teams reach for ODK or KoboToolbox for good reasons. They are free to start, they work on inexpensive phones, collection can continue without a connection and forms are written in a familiar spreadsheet-style format. For a household survey, a facility assessment or a baseline in a remote area, that is hard to beat.
The questions change when the data are meant to support a trial: which clinician entered this value, who changed it and why, how do you show an ethics committee or sponsor that only authorised people could see participant names, and how is a participant followed across several visits with defined windows. Those are questions about audit trail, access control, signatures and scheduling, and they should be answered by the system rather than by procedures around it. See ALCOA+ data integrity for the principles a trial database is judged against.
Capture records every change at field level with user, time, old value, new value and reason, keeps the audit trail exportable and does not let it be edited from the interface. For the full list of controls, see 21 CFR Part 11 compliant EDC. Part 11 compliance is a shared responsibility between the software and the sponsor's own validated use of it, whichever system you pick.
The habits of good field data collection carry over: short forms, clear codes, testing on a real device before launch and training users on a pilot. A data collection plan for thesis or field research can often be rebuilt as eCRFs with little rewording. What changes is that ranges, required fields and edit checks are set on the form, and corrections are queries with a recorded resolution.
What to compare
| Criterion | Why it matters | Capture |
|---|---|---|
| Audit trail | Who changed what, when and why | Field-level, append-only, with user, time, old and new value and reason |
| Scheduling | Repeat visits and diaries | Visit anchors, windows and reminders by email or SMS |
| Signatures | Consent and investigator sign-off | Verified eConsent; re-authenticated investigator signatures |
| Consent | Evidence that consent was given before data | eConsent with email one-time code, legal-binding acknowledgement and investigator countersignature |
| Identity separation | Minimum necessary access | Names at the site; coded IDs for researchers and sponsors |
| Data checks | Clean data at entry | Range and custom-value edit checks raise auto-queries |
| Locked structure | Forms that do not change mid-study unnoticed | Draft and approved forms; approved forms locked for live use |
| Offline entry | Collection without a connection | Not available today; plan for connectivity or a documented paper fallback |
| Cost | Budget for small studies | Free sandbox; no setup fee; pay only when you go live |
This table shows Capture's answers only. Ask ODK / KoboToolbox for theirs, and confirm current capabilities and terms directly with them.
Compliance controls
Every change is written to an append-only, hash-chained audit trail with user, time, old and new value and reason. Electronic signatures require password re-authentication and carry a meaning statement. Roles separate sites, and identifying data is segregated from study data at the database layer.
Weight changed 68.0 to 68.5 kg
Site coordinator · Reason: Transcription error
Query Q-0014 answered on Weight
Site coordinator · Reason: Source checked
Vital signs form locked
Data manager · Reason: Visit cleaned
Longitudinal studies
Each visit is anchored to screening, a milestone, an earlier visit, a fixed study day or a date recorded on a form, with a window and an enforcement mode. Questionnaires follow the schedule, reminders go out by email or SMS, and the status overview shows every participant against every visit.
Window -3 / +3 days around the anchored target date
Soft window
Stays available with a protocol deviation flag
Hard window
Locks outside the window
Warning only
Stays available with a warning
Auto-close
Marked missed when the window closes
Describe it or upload it, and let the AI draft the questions in the free sandbox.
Fit
ODK and KoboToolbox are often the right choice for field surveys, humanitarian and public health assessments, community data collection and any project that needs offline collection on low-cost devices, particularly when the project is not a regulated trial.
Capture fits studies where individual participants are followed over visits, clinical data are entered by site staff, consent and signatures must be evidenced, or a sponsor, ethics committee or regulator will ask how the data were controlled. Because it is browser-based and needs a connection, it is a weaker fit where offline collection is essential.
Identity and access
Site coordinators see participant names; researchers and sponsor-side users work with coded IDs. Identifying data is segregated at the database layer, sites see only their own participants, and data is encrypted with AES-256 at rest and TLS in transit, hosted in the EU or US.
Site coordinator
Jane Peterson
DOB: 04-Mar-1978
Subject 01-004
Sees direct identifiersResearcher
Subject 01-004
DOB: withheld
Coded ID only
Sees coded ID onlySame record, two roles. Row-level security enforces the split.
Switching
Export your form definition (the XLSForm file or the question list) and upload it, or describe the form, and Capture's AI drafts the eCRF for your review; nothing is saved until you approve it. Then add codes, ranges, edit checks and a visit schedule.
Keep the data already collected in its original export, documented, and start new collection in Capture from a defined date. Do not edit the archived export afterwards.
Test the full flow in the free sandbox first: entry, a failed edit check, a query, an e-signature and the audit trail export. If offline entry matters to your sites, agree a paper fallback in writing before you go live.
Evaluation
Agreements, access control and hosting checked.
Schedules, windows and reminders needed.
Audit trail with reasons required.
Consent or investigator sign-off needed.
Site separation and roles needed.
Part 11 or GCP expectations apply.
All comparisons
Every comparison uses the same approach: what to test, where each option fits, and Capture's own answers. See all of them on the comparisons hub at /compare.
They are data collection tools widely used for field research. For regulated trial data, check audit trail detail, signatures, role-based access, scheduling and validation evidence against your protocol and your sponsor's or regulator's expectations, using each project's own documentation.
Part 11 compliance depends on the system and on how the sponsor validates and uses it. Check the controls Part 11 describes, such as e-signatures with meaning statements and an audit trail with reasons, against the version and hosting you use. Capture provides these controls; compliance remains a shared responsibility.
Usually for visit scheduling, consent and signatures, per-field audit history with reasons, query management and roles that separate sites. These are routine EDC functions.
No. Offline entry is not available today in Capture. If your sites have no reliable connection, plan a documented paper fallback or keep a field tool for that part.
Upload the form file or describe the questions and the AI drafts the eCRF for your review. You then add edit checks, codes and the visit schedule.
Yes. Some teams use ODK or Kobo for community surveys and Capture for clinical data that needs trial controls.
The sandbox is free with every feature and no credit card. There is no setup fee, and you pay only once you go live with real participants.
Yes. The free sandbox includes every feature with sample data, no credit card and no time limit. You pay only when you go live.
From public positioning and the criteria teams tell us matter. We state only Capture's own capabilities as fact; confirm ODK / KoboToolbox's current offering with them.
Keep exploring
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The spreadsheet version of this question.
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Capture vs SurveyMonkey
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