Conduct↦Data Handling↦Data Handling↦Interim Lock
What is it? Why is it important?
Interim database locks (IL) are performed before all data has been collected due to required:
- Interim evaluation(s) of the study based on specification given in the study protocol (e.g. safety and efficacy concerns)
- Data cleaning processes during long term studies
Timing of data cleaning and query resolution should be planned both:
- Prior to an IL as the data will be used for statistical analysis and study interim evaluation
- After an IL lock with checks on an ongoing basis in order to detect incorrect and missing data
Database locks and evaluations during study conduct must always be based on specifications and rationales given in the study protocol (e.g. e.g. safety and efficacy concerns). Requests for an interim analysis during study conduct might also be forwarded by the DSMB and/or EC.
Data analysis not based on specifications in the study protocol carries the risk of corrupting the study, as the researcher is no longer an independent bystander of the study but become biased as to study outcome.
What do I need to do?
- Follow the timeline of interim database locks as defined in the study protocol
- As applicable, ensure data cleaning and query resolution are finalised before any IL
- Inform stakeholders of an upcoming IL including the expected lock duration
- Follow database lock procedures
- For the interim evaluation follow:
- Defined data export procedures for transfer to a statistical software system
- If applicable, ensure data remains blinded to the SP-INV and statistician during data evaluation
Database locks during study conduct can put increased pressure on site staff and people involved in data collection and management. Still, in order to ensure data quality and be prepared for upcoming locks, train and remind the staff to enter data consistently and regularly.
Safety and efficacy information provided by the interim analysis will help to determine whether the study should be continued, adapted or terminated.
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
ICH GCP E6(R2) – see in particular guidelines
- 5.5. Trial Management, data handling, and record-keeping