eCRF template · SafetyUpdated September 28, 2026

Adverse event eCRF template, field by field

The AE form every interventional study needs: term, onset, severity or CTCAE grade, seriousness criteria, causality, action taken and outcome. Copy it into a study in minutes, then adjust it to your protocol.

  • CDASH-style variables
  • Minimum dataset enforced
  • SAE sign-off built in

Free sandbox · No credit card · 21 CFR Part 11 aligned

Adverse events · AE-003
Subject 001-0042 · AE logAwaiting PI sign-off

Adverse event term (verbatim)

AETERM
Headache

Onset date

AESTDAT
UNK-JUN-2026

Partial date accepted

CTCAE grade

AETOXGR
12345

Serious?

AESER
NoYes

Relationship to study treatment

AEREL
Possibly related

Outcome

AEOUT
Recovering / resolving
Saved 10:42 by Site 001 coordinatorSave
Submission checks the minimum dataset

14

fields in the template, each mapped to a CDASH-style variable

6

seriousness criteria captured as separate flags

2

signatures: site attestation and investigator sign-off

1

audit trail row per changed field, per AE

What this template gives you

  • A repeating AE log form: one row per event, each with its own audit trail, so an event reported at Week 2 and resolved at Week 8 stays one record.
  • The regulatory minimum (term, onset date, seriousness, severity or grade, and causality for serious events) is required on submission, while partial drafts can still be saved.
  • Seriousness is recorded as six separate criteria, not one yes/no, so the SAE narrative and any expedited report start from structured data.
  • Field names follow CDASH-style conventions and the form carries the SDTM AE domain label, which keeps the hand-off to your programmers predictable.
  • Everything is editable: switch between mild/moderate/severe and CTCAE grading, add AESI questions, or link the form to your adverse event reporting workflow.

Design basics

What an adverse event eCRF has to capture

An adverse event is any untoward medical occurrence in a participant, whether or not it is considered related to the study treatment. That breadth is why the AE form is the most-used and most-queried form in most interventional studies: every headache, rash and lab abnormality the investigator judges clinically significant ends up here, and every one of them has to be complete enough to support safety analysis and, for serious events, expedited reporting.

A good AE eCRF separates the facts of the event (what happened, when it started and stopped) from the clinical judgements about it (how severe it was, whether it was serious, whether the drug caused it). Mixing the two in one free-text box is the single most common reason AE listings need weeks of cleaning before a database lock.

The minimum dataset

Regulators and sponsors expect at least an event term, an onset date, a seriousness assessment and a severity or toxicity grade for every AE, plus a causality assessment whenever the event is serious. Capture enforces exactly this set when a site submits the form. A coordinator can still save a partial draft while waiting for the investigator, but submission names the missing field instead of silently accepting an incomplete record, and the same check runs on the server so it cannot be bypassed.

Severity is not seriousness

Severity describes intensity: a severe headache is still a headache. Seriousness is a regulatory classification based on outcome: death, a life-threatening event, hospitalisation or prolonged hospitalisation, persistent or significant disability, a congenital anomaly, or an important medical event. A mild event can be serious, and a severe event can be non-serious. The template keeps them as separate questions, and breaks seriousness into six criteria so the reason an event qualified is never ambiguous.

Causality, action taken and outcome

The investigator assesses the relationship to study treatment on a fixed scale (the template uses not related, unlikely, possibly, probably and related, which you can collapse to a binary scale if your protocol does). Action taken with the study treatment and the event outcome use controlled lists, so they tabulate cleanly and map to standard terminology later.

Seriousness criteria
AE-003 · Serious = Yes

Criteria met (select all that apply)

Resulted in deathLife-threateningRequired or prolonged hospitalisationPersistent or significant disabilityCongenital anomaly / birth defectOther important medical event

Date site became aware

14-Jun-2026
Serious events raise a routed safety alert

Field specification

Every field in the AE eCRF template

Variable names follow CDASH-style conventions. Required-when rules are the defaults in the template; adjust them to your protocol and safety plan.

FieldVariableQuestion typeRequired whenNotes
Adverse event termAETERMTextAlwaysVerbatim term as reported. Coded to MedDRA later, never replaced.
Onset dateAESTDATDateAlwaysPartial dates such as UNK-JUN-2026 accepted.
Ongoing at end of study?AEONGOSingle choiceAlwaysDrives whether an end date is expected.
End dateAEENDATDateNot ongoingEdit check: cannot be before onset date.
SeverityAESEVSingle choiceIf grading by severityMild, moderate, severe.
CTCAE gradeAETOXGRLinear scale 1 to 5If grading by CTCAEUse instead of severity in oncology and many early-phase studies. Patients can report symptoms alongside with PRO-CTCAE.
Serious?AESERSingle choiceAlwaysYes opens the seriousness criteria.
Seriousness criteriaAESDTH, AESLIFE, AESHOSP, AESDISAB, AESCONG, AESMIEMultiple choiceSerious = YesAt least one criterion required.
Relationship to study treatmentAERELDropdownSerious = Yes (recommended always)Five-point scale by default.
Action taken with study treatmentAEACNDropdownAlwaysDose not changed, reduced, interrupted, withdrawn, not applicable.
OutcomeAEOUTDropdownAlwaysRecovered, recovering, not recovered, recovered with sequelae, fatal, unknown.
Treatment given for the AE?AECONTRTSingle choiceAlwaysYes prompts a matching concomitant medication entry.
Adverse event of special interest?Sponsor-definedSingle choiceIf the protocol defines AESIsLinks to the AESI form.
CommentsSponsor-definedLong textOptionalKeep clinical narrative out of coded fields.

Capture templates carry an OID and the SDTM domain label (AE) on the form. They are not a validated SDTM transformation: your programmers still map exports to SDTM.

Log, not visit form

One record per event, however many visits it spans

AEs do not respect the visit schedule. The template is built as a log form with repeating rows rather than a form repeated at every visit, so an event that starts between visits and resolves weeks later is one record that sites update, not five near-duplicates that data management has to reconcile.

  • Repeating rows, each with its own field-level audit trail.
  • Onset and resolution dates kept consistent by edit checks.
  • A clinically significant lab value can raise an AE without losing the lab entry.
  • MedDRA coding with sponsor-scoped dictionaries, or run the study without MedDRA.
Lab data and reference ranges
Adverse event · 01-004
AE term *Headache
Onset date *UNK-JUN-2026
Serious? *Yes
Severity / CTCAE grade *Grade 2
Causality to IMP *Required when serious
Save draftSubmit

Cannot submit yet

Causality is required because the event is serious.

Serious events

When Serious = Yes, the form starts the SAE workflow

Marking an event serious raises a safety alert straight away, routed by your study notification rules and acknowledged by the person who receives it. The SAE timeline then tracks the event from site awareness to investigator sign-off.

  • Site staff attestation plus PI or sub-investigator sign-off, including under delegation.
  • Every signature re-authenticated and stored with its meaning statement.
  • Safety listings and an E2B export for downstream safety systems.
Adverse event reporting software

SAE timeline

  1. SAE reported

    Day 0 · 09:12

  2. Safety alert acknowledged

    Medical monitor · 09:40

  3. Site staff attestation

    Study coordinator · 11:05

  4. AE sign-off (PI / Sub-I)

    Awaiting signature

Complete AE sign-off

Copy the AE template into a study and report a test SAE

The free sandbox has the full template library, sample data and the SAE sign-off flow.

Use this AE template free

Avoid rework

Six AE eCRF design mistakes that cost weeks at lock

Most AE queries are design problems, not site problems. These are the patterns data managers most often have to clean up after the fact, and how the template avoids them.

1. Severity and grade in the same study, used inconsistently

Pick one grading approach per study. If some sites grade with CTCAE and others with mild, moderate and severe, the safety tables cannot be pooled. The template has both fields, and you delete the one you are not using before approving the form.

2. Baseline conditions entered as AEs

Conditions present before consent belong in medical history. Only a worsening after consent is an AE. Put the rule in the form help text and make sure the medical history and demographics forms are completed at screening, before the first AE can be entered.

3. No partial dates

Participants often cannot remember the exact day a symptom started. Forcing a full date invites guesses that later conflict with source documents. Capture accepts partial dates and preserves them in exports.

4. Free-text outcome and action taken

Controlled lists make these fields countable. Free text has to be recoded by hand before any table can be produced.

5. One AE split into several records

A log form avoids the "new record every visit" pattern. When severity changes, follow your protocol convention (a new record per severity change, or the maximum severity on one record) and write it into the CRF completion guidelines.

6. AE treatment not linked to concomitant medications

If an AE was treated, the drug should appear in the concomitant medication log. The "treatment given" question in the template is a prompt to keep the two in step, and a data manager review of both logs before lock catches the gaps.

Before you approve the form

AE form review checklist

Forms move from draft to approved in Capture, and only approved forms appear in the casebook. Run through this list before approving.

Grading convention chosen

Severity or CTCAE grade, not both. Delete the unused field in the draft.

Reporting period defined

State in help text when AE collection starts (consent or first dose) and ends.

AESIs listed

If the protocol defines adverse events of special interest, keep the AESI question and its linked form.

Edit checks tested

End date after onset, criteria required when serious, causality required when serious. Test with sample entries in the sandbox.

SDV scope set

Mark AE term, seriousness and causality for source data verification; skip low-risk comment fields.

Blank form exported

Export the blank eCRF PDF for your ethics or IRB submission package.

FAQ

Questions about this template

Something not covered here? Ask us directly.

What is an adverse event eCRF?

It is the electronic case report form sites use to record adverse events during a clinical trial: the event term, dates, severity or grade, seriousness, causality, action taken and outcome. See what a CRF is for the wider context.

Is this AE template free to use?

Yes. The AE form is part of the Capture template library and available in the free sandbox. You pay only when a study goes live with real participants.

Does the template follow CDASH?

Field names follow CDASH-style conventions (AETERM, AESTDAT, AESER and so on) and the form carries the SDTM AE domain label. It is not a validated SDTM transformation, so your programmers still produce the SDTM datasets.

Should I use CTCAE grades or mild, moderate and severe?

Oncology and many early-phase studies use CTCAE grades 1 to 5. Other therapeutic areas commonly use mild, moderate and severe. Choose one per study and remove the other field before approving the form.

How are serious adverse events handled?

Answering Yes to Serious opens the seriousness criteria and raises a routed safety alert. The SAE timeline then tracks site attestation and investigator sign-off under an electronic signature.

Can AEs be coded to MedDRA?

Yes. MedDRA coding uses dictionaries scoped to your sponsor organisation. The verbatim term is always kept alongside the code.

Can a lab value create an AE?

Yes. A clinically significant lab result can raise an AE directly, without losing the lab data already entered.

Can I change the template?

Yes. Templates copy into your study as draft forms. Add, remove or reword fields, then approve the form when it matches your protocol.

Start with a complete AE form

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