Development↦Management↦Study Documents↦Source Data
What is it? Why is it important?
In studies, Source Data (SD) is the original information generated from some primary source such as a lab report, a participant questionnaire, or a medical examination.
In a study, data is generated, collected, and entered into a study database. The database is therefore not the primary data source, but contains transferred data = SD from some original record = Source Document (SDoc).
For example:
- The patient file (e.g. medical history, x-ray reports)
- Study specific examination documents (e.g. vital signs, height and weight, dietary habits, smoking, strength tests)
- Medical tests and kits (e.g. blood parameters, DEXA scan, HIV test results)
- Participant information (e.g. questionnaires, journal on the intake and handling of IMP/IMD, quality of life scores)
In order to ensure data quality, a study monitor compares SD with corresponding entries in the study database. Mistakes in the database must be corrected in order to correspond with the original SD.
where data was originally retrieved.
More
SD documentation is strictly regulated. Requirements includes that:
- SD entries must comply with ALCOAC principles (e.g. attributable, legible, contemporaneous, original, accurate, and complete)
- Copies of SDocs must be validated and certified so as to guarantee a failure free transfer of information
- Changes to SD must remain traceable and original entries must not be obscured
- SD entries into the study database, including potential changes, must have an audit-trail that documents what entries / changes were made by whom, when, and if applicable why
What do I need to do?
Source Data are variables needed for the evaluation of the study. As a SP-INV:
- Define the variables needed for your study (e.g. age, height, weight, blood pressure, blood haemoglobin values, quality of life).
- Define variable specifications (e.g. birth year, cm, kg, mmHg, g/dl, calculated score)
- Identify and create a list of those source documents where the SD variables are generated (e.g. medical examination, lab report, participant questionnaire)
- List all study variables in your study protocol
- Develop a Case Report Form (eCRF) for the collection of all your variables during study conduct
- Dubmit the protocol and the eCRF to the Ethics Committee (EC) for approval. Changes to any of these documents always require EC approval
Tto guarantee the quality of your data, plan quality checks that compare variables in the database with the original SD in the SDocs. For this purpose, grant easy access to monitors during the monitoring of your study.
More
A certified copy of a SDoc can also be defined as a SDoc, as long as the process used to generate the copy has been thoroughly validated. This guarantees that the copy is a true reflection of the original SDoc.
This validation process might be especially useful for archiving, when the original SDoc is not expected to remain legible during the entire archiving period (i.e. some archiving requirements exceed 20 years)
Where can I get help?
Your local CTU↧ can support you with experienced staff regarding this topic
Basel, Departement Klinische Forschung, CTU, dkf.unibas.ch
Lugano, Clinical Trials Unit, CTU-EOC, www.ctueoc.ch
Bern, Clinical Trials Unit, CTU, www.ctu.unibe.ch
Geneva, Clinical Research Center, CRC, crc.hug.ch
Lausanne, Clinical Research Center, CRC, www.chuv.ch
St. Gallen, Clinical Trials Unit, CTU, www.kssg.ch
Zürich, Clinical Trials Center, CTC, www.usz.ch
References
ICH GCP E6(R2) – see in particular guidelines
- 1.51 Source documents definition
- 4.9.0 Records and Reports
- 6.10 Direct Access to Source Data / Documents
ISO 14155:2020 Medical devices (access liable to cost) - see in particular sections
- 7.5.3 Source documents
- 7.8 Document and data control
- 9.2.4.5 g Monitoring