Major Responsibilities of a Project Biostatistician in Clinical Trials

In a clinical trial, the project biostatistician is responsible for statistical design, analysis strategy, quality oversight, and scientific interpretation throughout the study lifecycle, ensuring that trial results are scientifically sound, regulatory-compliant, and interpretable.

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I. Study Design Phase

• Participate in trial design discussions
• Lead or support:
• Statistical definition of primary and secondary endpoints
• Sample size and power calculations
• Randomization and stratification schemes
• Ensure the design:
• Is statistically valid
• Is feasible for analysis
• Meets regulatory expectations (FDA, EMA, ICH)

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II. Statistical Analysis Plan (SAP)

• Author, review, or approve the SAP, including:
• Analysis methods and statistical models
• Estimand definitions
• Handling of missing data and intercurrent events
• Ensure the SAP:
• Is consistent with the protocol
• Is clear, implementable, and auditable

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III. Study Conduct Phase

• Provide blinded statistical support:
• Assess data trends and event rates without accessing treatment assignments
• Support enrollment and data quality assessments
• Collaborate with data management and programming teams to:
• Ensure data structures support planned analyses
• Support the DMC (indirectly):
• Contribute to statistical sections of the DMC charter
• Coordinate data preparation for independent/unblinded statisticians
• Maintain blinding by not participating in unblinded DMC discussions

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IV. Quality Control and Compliance

• Conduct and/or oversee statistical QC:
• Review TFLs for statistical accuracy and consistency
• Assess the impact of QC findings
• Ensure:
• Analyses adhere to the SAP
• Study blinding is preserved
• Processes are well documented and traceable

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V. Results Interpretation and Reporting

• Interpret results from a statistical perspective:
• Robustness and sensitivity of findings
• Consistency across analyses
• Statistical limitations
• Author or review:
• Statistical sections of the Clinical Study Report (CSR)
• Statistical responses to regulatory questions

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VI. Cross-Functional Communication

• Explain statistical concepts and results to non-statistical stakeholders
• Support:
• Internal project decision-making
• Audit and inspection responses

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VII. Activities Typically Not Led by the Project Biostatistician

• Routine TFL programming
• Execution of validation activities
• Unblinded interim analyses or DMC decision-making
• Final medical or business decisions

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One-Sentence Summary

The project biostatistician plays a central role across the clinical trial lifecycle by defining statistical strategy, ensuring analytical quality and compliance, and providing scientifically sound interpretation of trial results.