The Systems Trial Data Move Through

Part of Clinical Research Associate (CRA) Training: Data, Documentation and Trial Supplies.

About 6 minutes. Free, in your language, no account needed.

Why this matters

Trial data pass through several systems, and the places where they hand off are where errors live. A CRA who understands the map can predict where a discrepancy came from instead of chasing it.

You do not need to be technical. You need to know what each system is for and what your responsibility is in each.

The systems

Electronic data capture (EDC). The core system where case report form data are entered and stored. Visit-based forms, built-in edit checks, query management, an audit trail recording who changed what, when and why, and role-based permissions. This is where you spend most of your data time.

ePRO and eCOA. Electronic patient-reported outcome and clinical outcome assessment systems, capturing data directly from participants or clinicians on tablets, phones or web portals. Symptom diaries, quality-of-life questionnaires, pain scales. They reduce transcription error, timestamp entries and can remind participants.

eSource and the site's electronic health record. eSource means original data recorded electronically. The health record is the site's own system, capturing routine care and sometimes trial data. Where it is source, you need appropriate access, on site or remotely.

Clinical trial management system (CTMS). The sponsor's or CRO's operational tracker: sites, contacts, visit schedules and completion, enrollment and participant milestones, monitoring visits and reports, issues and actions. Sites rarely use it; what you enter about a site lives here.

Electronic trial master file (eTMF). The official repository of essential records: protocol and amendments, Investigator's Brochures, ethics approvals, contracts, financial disclosures, monitoring reports and follow-up letters, and training records.

Interactive response technology (IRT, IVRS, IWRS or RTSM). Randomization and trial supply management: assigning treatment, managing shipment requests and site inventory, and recording drug assignment and dispensation.

Safety or pharmacovigilance systems. Where the sponsor processes adverse event and serious adverse event data.

How data flow, and where they break

Source — the health record, ePRO, laboratory systems — is entered or transferred into EDC. From EDC the data go to data management for cleaning and locking, and to biostatistics for analysis. Safety data also reach the safety database, directly or by transfer. Operational information populates the CTMS, document information the eTMF, and product and randomization information the IRT.

Nothing propagates automatically unless it was built to. A randomization recorded in the IRT still has to be reflected in EDC. An event reported on a safety form still has to be entered on the EDC adverse event page. Most reconciliation queries exist because someone assumed otherwise.

Learn the three reconciliations you will meet repeatedly:

Your responsibilities per system

EDC. Confirm data entry is complete and timely. Verify entries against source. Raise, review and help resolve queries. Watch for patterns: repeated errors, systematic missing data, frequent overrides of edit checks. Confirm site users have appropriate access and completed training.

ePRO and eCOA. Confirm participants were trained on the device or app. Verify devices are assigned correctly, functioning, charged and replaced when lost or broken. Check that entries align with clinical data such as visit dates. Review compliance metrics: missed entries, late or back-entered data. Escalate technical problems through the sponsor's helpdesk.

eSource and health records. Confirm source records exist for every data point you verify. Check that entries are contemporaneous, attributable and complete. Understand the site's workflow well enough to know where transcription happens and what could go wrong there.

CTMS. Schedule and document your visits. Record site contacts and communications. Track enrollment and participant status. Document issues and actions, including resolution.

eTMF. Ensure documents for your sites are uploaded, complete and correctly indexed. Review completeness metrics and close gaps with the site and the sponsor team.

IRT. Verify site staff have active, appropriate access. Check that randomization and dosing events recorded in the IRT match EDC, pharmacy records and product accountability logs. Investigate failed or incorrect randomizations and discrepancies against physical inventory.

Safety systems. Ensure the site knows the reporting route and timelines, that reports use the correct channel, and that events reconcile between the safety database and EDC.

Access, training and security

In practice

Leah finds a discrepancy at a VT-301 site: the IRT shows kit 4172 dispensed to participant 019 on 14 May, while the EDC dosing page records kit 4127 on the same date.

She goes to the pharmacy dispensing log, which is source. It records 4172, matching the IRT. The transposed number is in EDC.

She raises a query rather than correcting it herself, because she does not enter site data. The site corrects EDC through the system's correction function, preserving the audit trail.

She then checks whether it is isolated. It is: the coordinator had entered several kit numbers from a handwritten note rather than from the dispensing log.

The finding Leah writes is about the transcription step, not the digit. She recommends entering kit numbers directly from the dispensing log, and the site removes the intermediate note.

Errors live at hand-offs. Find the hand-off and you find the error.

Key takeaways