Examples
Worked examples
- Is an instance
A subject's vital signs recorded directly onto a hospital nursing flowsheet during a clinic visit are source data; the flowsheet is the source document -- even though the eCRF field for that visit will later be filled in from it.
- Is an instance
A central laboratory's PDF report showing a subject's vitamin D level is the source document for that lab value; whoever enters the number into the EDC system is transcribing from source, not creating it.
- Is an instance
A subject-completed paper diary tracking daily pain scores is itself the source document for that data, because it is the first and only place the observation was recorded by the person experiencing it.
- Is an instance
An investigator who examines a participant and records blood pressure directly into a study-specific worksheet (with no separate clinic chart entry made) has made that worksheet the source document for that reading -- the tool becomes source only when there is no earlier original record it was transcribed from.
Counter-examples
Looks similar, but isn't
- Not an instance
A monitor's own visit-tracking log noting that a source document 'appeared complete' is not itself source documentation -- it is the monitor's assessment record, not an original clinical record of the subject's condition or trial activity.
- Not an instance
A site coordinator's personal notebook summary of a subject's symptoms, written up later from memory after the actual encounter note was already documented in the medical record, is not the source document -- the original medical-record entry made at the time of the encounter is; a later, non-contemporaneous re-creation does not satisfy ALCOA-C even if it is more legible.
Editorial commentary
Frequently Asked Questions
What’s the difference between source data and source documents?
They describe the same material from two angles. Source data is the information itself — the clinical findings, observations, or measurements captured during a trial. Source documents are the original records that contain that information, such as a medical chart, a lab report, or a subject diary.
What are examples of source documents in a clinical trial?
Common source documents include a hospital nursing flowsheet recording vital signs at a clinic visit, a central laboratory’s report of a subject’s test results, a subject-completed paper diary, and an investigator’s original clinic-chart entry. Which record counts as the source document for a given data point depends entirely on where that value was first captured, not on the type of document.
Does a transcription count as a source document?
Not usually. If a value already exists in an earlier original record, such as a hospital chart, then copying it onto a separate study worksheet or into an EDC system creates a transcription, not a new source document. A worksheet only becomes the source document itself when there is no earlier original record and it is the first place the observation was recorded.
What are the ALCOA-C principles for source documentation?
ALCOA-C is the standard used to judge whether source documentation is inspection-ready. Records must be Attributable (showing who recorded them and when), Legible, Contemporaneous (recorded at the time of the observation, not backfilled), Original (the first record, or a verified certified copy), Accurate, and Complete.
What does ICH E6(R2) say about source data and source documents?
ICH E6(R2) Section 1.51 defines source data as all information in original records and certified copies of original records of clinical findings, observations, or other activities in a trial that is necessary for reconstructing and evaluating the trial. Section 1.52 defines source documents as the original documents, data, and records that contain that information.
Why does source documentation matter in a clinical trial?
It is what allows a trial to be reconstructed and evaluated after the fact — regulators and auditors rely on it to confirm that reported data matches what was actually observed. That is why source documents are judged against the ALCOA-C principles rather than simply accepted at face value.
Machine-readable encodings
Use in your systems
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vocab-identifier="https://casrai.org/dictionary/"
vocab-term="Source Documentation (Source Documents / Source Data)"
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"description": "Source documentation is the body of original records -- medical charts, laboratory reports, imaging studies, pharmacy dispensing logs, subject diaries, correspondence, and automated instrument printouts -- in which clinical findings, observations, or other trial-related activities are first captured, at the point and time they occur. The information those records contain is source data; the records themselves are source documents. A record only counts as a source document for a given data point if it is where that data point was originally recorded -- a transcription onto a separate worksheet or data-collection tool is not itself a source document unless no earlier original record exists. Per ICH E6(R2) Section 1.51, source data is 'all information in original records and certified copies of original records of clinical findings, observations, or other activities in a clinical trial necessary for the reconstruction and evaluation of the trial'; Section 1.52 defines source documents as the original documents, data, and records containing that information. To be inspection-ready and support reconstruction of the trial, source documentation must satisfy the ALCOA-C principles: Attributable (identifies who recorded it and when), Legible, Contemporaneous (recorded at the time of the observation, not backfilled), Original (the first record, or a verified certified copy), Accurate, and Complete.",
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