PAD trials mix hard events (amputation, revascularisation, cardiovascular death) with measurements that depend on who holds the stopwatch: ankle-brachial index and treadmill walking tests. Capture gives each its own form, queries the gaps and keeps one audit trail. Free sandbox, no credit card, pay only at go-live.
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| Assessment | Screen | Baseline | Wk 12 | Wk 24 | Wk 52 |
|---|---|---|---|---|---|
| ABI / toe-brachial index | |||||
| Treadmill walking test | |||||
| Walking questionnaire | |||||
| Vascular quality of life | |||||
| Limb and CV events review | |||||
| Bleeding and adverse events |
x = visit form
What a PAD trial needs from its EDC
The study data
PAD is three populations under one name. Intermittent claudication trials, testing exercise programmes, cilostazol-like drugs or new vasoactive agents, measure walking: peak walking time or maximal walking distance on a treadmill, claudication onset distance, and questionnaires such as the Walking Impairment Questionnaire (scored 0 to 100 by category, covering distance, speed and stair climbing) and PAD-specific quality-of-life tools like VascuQoL. Chronic limb-threatening ischaemia (CLTI) trials look at wound healing, amputation-free survival, limb salvage and revascularisation patency. Cardiovascular outcome trials in PAD populations, for example low-dose colchicine or antithrombotic strategies in registered protocols, use a composite of major adverse cardiovascular events (MACE) and major adverse limb events (MALE) over several years.
The composite definitions differ trial by trial. In published registry and trial protocols MACE usually includes cardiovascular death, non-fatal myocardial infarction and non-fatal stroke, sometimes ruptured aortic aneurysm. MALE commonly covers critical limb ischaemia, urgent revascularisation for acute limb ischaemia and major amputation, with an extended version adding revascularisation for new or worsening claudication. Whatever your definition, each component needs its own date, type and, for amputation, level (for example at or above the ankle). Build one event form per event class and make the classification fields required.
Treadmill testing is where claudication datasets lose credibility. Protocols vary: a constant 2.5 km/h flat test, a graded test with increasing incline, or a constant-load test at a fixed incline. An analysis of treadmill testing in PAD trials reported substantial site-to-site variability and a large placebo response, attributed in part to inconsistent administration. A site eCRF form that records protocol used, speed, grade, claudication onset time, peak time, stop reason (claudication, other symptoms, cardiac, completed maximum) and tester initials lets monitors see inconsistency early rather than at analysis.
Test conditions
Protocol
TMPROTClaudication onset time
COTPeak walking time
PWTReason test stopped
TMSTOPAnkle systolic pressure post-exercise
APOSTRecorded within protocol recovery window
Protocol to build
| Protocol element | What the data looks like | Where it lives in Capture |
|---|---|---|
| Qualifying haemodynamics | ABI or toe-brachial index, side, resting and post-exercise | Site eCRF form with range edit checks; values entered as measured |
| Treadmill test | Protocol, speed, grade, onset, peak, stop reason | Treadmill form each visit |
| Walking and quality-of-life questionnaires | Scored domains | Participant questionnaires on a phone link; licences stay with study documents |
| MACE and MALE events | Type, date, level, urgent versus elective | Event forms, one per class, with required classification fields |
| Revascularisation procedure | Vessel, approach, device, date | Procedure form with repeating rows for each lesion |
| Wound assessment (CLTI) | Site, size, grade, healing date | Repeating wound table with per-row audit trail |
| Antithrombotic therapy and bleeding | Agents, doses, bleed type and severity | Concomitant medications and adverse event forms |
Capture records ABI values as entered and does not compute index ratios; add that to your own checks if needed.
Build the walking test and event forms in the free sandbox and share the working build with every site. No credit card.
Events and safety
Outcome trials rely on events being found, documented and confirmed. Sites enter each suspected event on a form that captures date, type, hospitalisation, procedure and source documents held at the site, and the study team can run source data verification per field on the fields that drive the endpoint. Many PAD outcome trials send events to an independent committee for adjudication. That committee process is run by the sponsor or a vendor; Capture holds the event data and exports it by site and date range for the committee, but it does not run the adjudication workflow itself.
Antithrombotic therapy is the second data pressure point. Participants may be on aspirin, a P2Y12 inhibitor, low-dose rivaroxaban or combinations, and the protocol sets which are permitted. A concomitant medication table with start and stop dates lets you query illegal combinations, and bleeding events (major, clinically relevant non-major, minor) belong on a dedicated bleeding section of the adverse event form. For the cardiometabolic neighbours see EDC for heart failure trials and EDC for hypertension trials.
Participants with PAD often have diabetes and kidney disease, so renal function and glycaemic measures sit in the baseline and safety forms, with eGFR calculated from entered creatinine. Blood pressure and heart rate are collected as vital signs at each visit.
Build sequence
Upload the protocol. The AI study builder proposes visits and forms for you to review; nothing is saved without a person.
Mark qualifying values required and add range checks for impossible pressures.
One per event class, with date, level and classification fields required.
Participant walking and quality-of-life tasks with reminders, from a secure phone link.
Have each site coordinator enter a practice participant and review the queries.
Approved forms lock for live use. You pay once real participants are enrolled.
Multi-site delivery
PAD trials recruit from vascular clinics, interventional suites and sometimes primary care, each with different equipment. QR-code enrolment, site-level participant numbering and the site coordinator portal keep this manageable, and by-site exports show which site's treadmill data look different. Risk-based approaches to monitoring and SDV, described in risk-based monitoring and SDV software, pair well with endpoint-critical fields such as events and the qualifying ABI.
Long outcome trials run for years. Soft-deletes only, a field-level audit trail and exportable change history keep the record inspectable across that span. Capture is suitable for Phase 1 to 3 studies, including large Phase 3 programmes.
No ABI calculator is built in. Sites enter the measured pressures and index, and range edit checks catch impossible values.
Yes. Build one event form per class with required type, date and, for amputation, level fields, then export for analysis or committee review.
No. It holds the event data and exports by site and date range; the adjudication process is run outside the product.
Yes, through a secure link with reminders and a completion window. Any licence for a published questionnaire stays with your study documents.
Use one treadmill form with protocol, speed, grade, onset, peak time and stop reason as required fields, then review by-site exports during the study.
Yes. Capture is suitable for Phase 1, 2 and 3, with multi-site enrolment tools and by-site exports.
Free sandbox with every feature, no credit card; you pay at go-live. See the pricing page.
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