What is it? Why is it important?

An Interim Analysis (IA) is done before all data collection is complete in order to evaluate study safety and efficacy while the study is still ongoing, such as:

  • Safety concerns (e.g. a potentially high frequency of adverse events during study treatment)
  • Efficacy concerns (e.g. treatment effect compared to placebo is highly superior or has no added benefit)

Timing and rational of an IA must be documented in the study protocol.

More

An IA can also be beneficial in studies lasting for long periods of time. This might facilitate data cleaning during study conduct and ensure data quality. In addition, IAs and data publications might be an integral strategy of longitudinal studies.

In order to protect participant safety and rights the EC might request that an IA be performed during study conduct.

A Data Safety Monitoring Board (DSMB) consists of a group of individuals independent of the study, who are experts in relevant areas.

The board reviews the accumulated data and findings from an IA and advises the SP-INV on the continued:

  • Safety of study participants
  • Validity of the study
  • Scientific merit of the study.

What do I need to do?

  • Describe the rational and requirement of an IA in your study
  • Plan the appropriate timing of an IA (e.g. upon inclusion of 10 study participants, after 6 month study conduct months, on a quarterly basis)
  • Frequency and rational for repeated IAs
  • Type of statistical analysis used
  • Describe implications based on analytical results (e.g. upper- lower tolerability defining study continuation, adaptations, or study stop)
  • Plan to set-up a DSMB who provides expert advice on how to proceed with the study

For more information refer to Statistics in this Study Guide.

Where can I get help?

Your local CTU can support you with experienced staff regarding this topic

References

ICH GCP E6(R2) – see in particular guidelines

  • 5.4.1 Interim report
  • 5.5 Trial Management, data handling, and record keeping
  • 6.9.1 Statistics, interim analysis

ICH E9 – Statistical Principals for Clinical Trials

ISO 14155:2020 Medical devices see in particular section (access liable to costs)

  • 6.2 Risk management
  • A.7 Statistical design and analysis
Abbreviations
  • CTU – Clinical Trials Unit
  • DSMB - Data Safety Monitoring Board
  • IA – Interim Analysis
  • ICH-GCP – International Council for Harmonisation - Good Clinical Practice
  • ISO – International Organization for Standardization
  • SP-INV – Sponsor-Investigator
Development ↦ Management ↦ Quality Mgmt. System ↦ Interim Analysis
Study
Basic

Provides some background knowledge and basic definitions

Basic Protocol
Basic Statistics
Basic Monitoring
Basic Drug or Device
Basic Biobanking
Concept

Starts with a study idea

Ends after having assessed and evaluated study feasibility

Concept Protocol
Concept Statistics
Concept Drug or Device
Concept Biobanking
Development

Starts with confidence that the study is feasible

Ends after having received ethics and regulatory approval

Development Protocol
Development Statistics
Development Drug or Device
Development Biobanking
Set-Up

Starts with ethics and regulatory approval

Ends after successful study initiation

Set-Up Protocol
Set-Up Ethics and Laws
Set-Up Statistics
Set-Up Drug or Device
Set-Up Biobanking
Conduct

Starts with participant recruitment

Ends after the last participant has completed the last study visit

Conduct Protocol
Conduct Statistics
Conduct Drug or Device
Conduct Biobanking
Completion

Starts with last study visit completed

Ends after study publication and archiving

Completion Protocol
Completion Statistics
Completion Drug or Device
Completion Biobanking
Current Path (click to copy): Development ↦ Management ↦ Quality Mgmt. System ↦ Interim Analysis

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