Development↦Statistic Methodology↦Statistics in the Protocol↦Interim Analysis
Was betrifft es? Warum ist das wichtig?
An Interim Analysis (IA) is a statistical evaluation of collected study data before the completion of the study. The aim is to assess whether the study can continue as planned.
The results of an IA may lead to a reassessment of the sample size (e.g. if the assumptions made during study planning do not align with the observed data) and/or to early study termination.
Early study termination may be due to::
- Futility: there is a high probability that the intervention is ineffective or has only minimal benefit
- Safety: there are unacceptable participant safety risks (e.g. with more adverse events in the intervention group compared to the control group, resulting in an unacceptable risk-benefit-ratio)
- Efficacy: due to a significant beneficial treatment effect, the study success is declared early. Continuing the study without providing the intervention to all participants would be unethical (e.g. principles of ethics)
Was muss ich befolgen?
As a SP-INV, assess whether an interim analysis is needed to identify:
- Risks to study quality (e.g. risks to the study’s critical quality factors)
- Participant safety
- Requirement for early study termination due to clear evidence of treatment efficacy or lack thereof
As a SP-INV:
- Discuss the planned IA with a statistician, as IA results may affect the sample size calculation and overall study design
- Describe the IA in the study protocol, and, if applicable, in the Statistical Analysis Plan (SAP). Include the type, timing, and frequency of IAs
- Define the composition and requirement of the independent Data Safety Monitoring Board (DSMB), also named the Independent Data Monitoring Committee (IDMC).
Note: Interim analyses are usually conducted by an independent statistician, with IA results provided to the DSMB / IDMC. Based on IA results, the committee can provide important impartial recommendations, thereby supporting the SP-INV on how to proceed with the study.
Wo kann ich Hilfe anfordern?
Your local Research Support Centre↧ can assist you with experienced staff regarding this topic
Basel, Departement Klinische Forschung (DKF), dkf.unibas.ch
Lugano, Clinical Trials Unit (CTU-EOC), ctueoc.ch
Bern, Department of Clinical Research (DCR), dcr.unibe.ch
Geneva, Clinical Research Center (CRC), crc.hug.ch
Lausanne, Clinical Research Center (CRC), chuv.ch
St. Gallen, Clinical Trials Unit (CTU), h-och.ch
Zürich, Clinical Trials Center (CTC), usz.ch
SCTO Research Tools & Resources
Video
References
ICH GCP E6 (R3) – see in particular
- 2.6 Investigator: Premature termination or suspension of a trial
- 3.10.1 Risk management
- 3.17.1 Reports: The premature termination or suspnesion of a trial
ICH Topic E9 – see in particular
- 4.1 Trial monitoring and interim analysis
- 4.5 Interim analysis and early stopping
- 7.2.1 Efficacy data
- 7.2.2 Safety data