A challenge study compresses a lot of data into a few weeks: an inoculation time, round-the-clock observations in a unit, symptom scores, viral load samples and tight safety rules. Capture holds them in one study with one audit trail. Build and test free; pay only at go-live.
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| Assessment | Screen | Day -1 | Day 0 | Day 1-7 | Day 14 | Day 28 |
|---|---|---|---|---|---|---|
| eConsent and eligibility | ||||||
| Inoculation (date and time, lot) | ||||||
| Vitals and symptom checks (unit) | ||||||
| Viral load sample results | ||||||
| Symptom diary (phone) | D | D | D | |||
| Adverse events |
x = done, D = participant diary. Demo data only.
What challenge trial data looks like
Study design
Challenge studies serve several purposes: model characterisation and dose finding for a new strain or model, vaccine or antiviral efficacy tests where participants receive an intervention and then challenge, and mechanistic studies of immunity. A published SARS-CoV-2 characterisation study aimed to find the dose that produced well-tolerated infection in more than half of participants, and an adaptive protocol started with three sentinel participants followed by seven more as a stepwise risk-mitigation approach. Treat these as examples of design patterns rather than templates.
Dose escalation and sentinel groups mean cohort records must be easy to read at a glance and decisions documented against the data cut. Intervention-then-challenge designs add randomization and blinding, so blinded staff must not see arm. In Capture, blinded roles never receive treatment-arm values, enforced by masked database views and row-level security rather than by the interface alone. Randomization and blinding are covered at clinical trial randomization software and blinded and unblinded role management.
Inoculation and unit observations
Record inoculation as a date and time, the product lot and the person who gave it, then observations on a fixed cadence. Calculated fields show hours since inoculation as read-only values during entry, and range checks raise an automatic query when a value is outside limits. Repeating rows hold each sample and observation, and each row has its own audit trail. The form below is demo data.
Inoculation date and time
Observation date and time
Hours since inoculation
Calculated, read-only
47.6 h CalculatedTemperature
VSORRESAbove limit: query raised
Oxygen saturation
VSORRESBuild the inoculation, unit observation and sample forms in the free sandbox and test the queries before the ethics submission.
Symptoms and viral load
Core endpoints in published challenge work are viral kinetics and symptom kinetics. Symptoms are usually scored on a checklist several times a day while in the unit and by diary after discharge; sample results arrive from a laboratory on a schedule. Plan the data model first: which symptoms, which scale, how often, which sample types, and which lab values are primary versus supportive. See clinical trial endpoints and primary endpoint.
In Capture the in-unit symptom checklist is an eCRF form with a repeating row per assessment, and the home diary is an ePRO questionnaire on the participant's phone with the same audit trail. Lab results go in a lab table (analytes as rows, unit, result and reference-range columns), with the AI form drafter able to build the table from a file you upload, for human review before saving. Exports give you a wide CSV/Excel with a data dictionary and, for submissions, SDTM datasets as SAS XPT with Define-XML. Capture does not connect to lab instruments or analysers; results are entered or loaded by your team.
For planning, see sample size calculation; for the lab side see lab results eCRF and lab unit converter.
Safety
Your protocol sets the actual criteria. These are the data points teams commonly build.
| Safety element | What is recorded | How Capture handles it |
|---|---|---|
| Adverse events | Onset, severity, relatedness, outcome, action. | Adverse event and AESI forms with an audit trail per entry. |
| Serious adverse events | Seriousness criteria and reporting times. | SAE form and safety reporting workflow; see the SAE timelines guide. |
| Stopping and discharge criteria | Clinical thresholds checked at each observation. | Edit checks flag values; the decision itself stays with the clinician. |
| Rescue or antiviral treatment | Drug, dose, time. | Concomitant medication repeating rows. |
| Sentinel and escalation decisions | Review date, data cut, decision. | Dedicated form with signer; exports for the safety committee. |
| Long-term follow-up | Late symptoms and contact. | ePRO follow-up questionnaires on the participant's phone. |
Capture records safety data and flags out-of-range values. Clinical monitoring and treatment decisions remain with the study clinicians.
Set-up
The AI study builder drafts visits and forms; your team reviews every one before it is saved.
Define Day 0 as inoculation and set observation windows around it.
Range limits, hours since inoculation, and queries routed to the right role.
Clinicians, coordinators, blinded assessors and safety reviewers see only what they should.
Enter sample participants, test e-signatures and the audit trail, and go live only when ready.
A study in which healthy volunteers are deliberately exposed to a pathogen or antigen under controlled, supervised conditions to study infection, immunity or the effect of a vaccine or treatment. It is also called a controlled human infection model (CHIM).
Capture can hold the study data: consent, time-stamped inoculation and observation forms, symptom diaries, lab results, adverse events and the audit trail. It does not replace clinical monitoring, laboratory systems or ethics and regulatory approvals.
Yes, date and time fields are available, and calculated fields can show hours or minutes between two date-times as read-only values.
No integrations with monitors, analysers or lab systems are claimed. Data is entered by site staff or loaded by your team.
Yes. Capture ePRO sends questionnaires to the participant's phone, with email reminders, in the same study and audit trail.
Blinded roles never receive treatment-arm values; this is enforced in masked database views and row-level security, not just the interface.
Reviews describe a particularly rigorous ethical review and requirements such as GMP-grade inoculum, but the route depends on the country and regulator. Ask your regulatory team; Capture makes no claim about approvals.
Open the free sandbox, upload your protocol or build the forms, and test with sample participants. No credit card and no time limit; you pay only at go-live.
Build forms, checks and diaries free. No credit card; pay only at go-live.