<img src="https://secure.intelligence52.com/795232.png" style="display:none;">

An Introduction To Biostatistics In Clinical Trials

By Statistical Consultancy Team
May 16, 2025

Biostatistics in Clinical Trials

Biostatistics is a specialised field of statistics focused on analysing biological and medical data. In clinical trials, it plays a pivotal role in the design, execution, and reporting of research. By providing scientific tools and methodologies, biostatistics ensures that study findings are robust, valid, and applicable to real-world healthcare scenarios.

The field has gained significant recognition, with biostatisticians serving not only as technical experts but also as strategic partners in clinical teams. They actively contribute to solving study-related challenges, drive innovation in statistical methodologies, and ensure compliance with regulatory standards. Ultimately, biostatisticians bridge the gap between raw data and actionable insights, supporting the development of safe, effective, and evidence-based medical treatments.

Biostatistics is used throughout the entire lifecycle of clinical trials to ensure validity and reliability. Its key applications include:

1. Assessing Efficacy – measuring and comparing treatment effects.
2. Evaluating Safety – quantifying side effects and risk profiles.
3. Forecasting Outcomes – informing clinical decision-making and personalised medicine.
4. Ensuring Transparency – promoting reproducibility and building trust among regulators and healthcare providers.

What is the Role of a Biostatistician in a Clinical Trial?

Biostatisticians offer expertise in data analysis and interpretation to help prove an investigational drug's safety and efficacy. They specifically support the following areas:

Study Design and Statistical Planning
Biostatisticians collaborate with researchers to create robust study protocols aligned with the trial's objectives. They determine appropriate methodologies and optimise designs (e.g. adaptive clinical trials, stratified randomisation, blinding) to minimise bias and maintain scientific rigour. They also develop Statistical Analysis Plans (SAPs) to guide data collection, management, analysis, and reporting.

Sample Size Determination and Randomisation
Calculating sample sizes that minimise error increases confidence in conclusions. In parallel, randomisation – whether simple, stratified, or block – ensures fair participant allocation, reduces selection bias, and improves the generalisability of results. Biostatisticians tailor these strategies to each study's unique needs.

Data Monitoring and Interim Analyses
Biostatisticians help maintain data quality and integrity throughout a trial's duration. They conduct interim analyses to assess whether a drug is demonstrating sufficient efficacy, or if safety concerns necessitate early stopping, thus safeguarding participant welfare and conserving resources.

Data Analysis and Interpretation
Transforming raw data into actionable insights is a major function of biostatistics. Biostatisticians apply statistical tests, regression methods, and longitudinal analyses to reveal relationships between variables, identify treatment effects over time, and support evidence-based conclusions.

Regulatory and Ethical Compliance
Ensuring adherence to regulatory and ethical standards is paramount. Biostatisticians align trial methodologies with guidelines from bodies such as the FDA, EMA, or ICH, and work closely with Data Safety Monitoring Boards (DSMBs) to uphold the integrity of clinical research.

Collaboration and Communication
Effective communication is crucial. Biostatisticians must present and interpret statistical findings clearly for multidisciplinary teams, building stakeholder trust, and enabling informed decisions that advance medical innovation.

Study Design Considerations

When planning clinical trials, researchers must address key elements to ensure rigour and regulatory compliance (e.g. NIH in the US, MHRA in the UK, EMA in the EU). Essential considerations include:

  • Defining the research question
  • Minimising variation
  • Randomisation, stratification, and blinding
  • Choosing a control group
  • Specifying the target population and entry criteria
  • Endpoints (primary and secondary outcomes)
  • Calculating sample size
  • Planning interim analyses

In broad terms, randomised clinical trials (RCTs) test interventions in a controlled manner, while observational studies reflect real-world scenarios. As mentioned, trial designs can be optimised through modern methodologies that allow for modifications without compromising data integrity.

More Traditional Design Methodologies

Basket Design
Tests a targeted treatment across multiple diseases that share specific molecular or genetic markers.

Umbrella Design
Evaluates multiple targeted therapies within a single disease setting, matching patients to the most appropriate intervention based on biological factors.

Platform Design
Examines several interventions concurrently using a single control group, enabling efficient comparisons and timely adjustments.

 

Beyond traditional approaches, biostatistics incorporates Bayesian statistics and machine learning (ML) to enhance predictive modelling and decision-making in clinical research:

Bayesian Statistics
Allows researchers to refine estimates as new data become available, proving especially useful in adaptive trials and personalised medicine.

Machine Learning
Analyses large, complex datasets to aid in disease protection, drug discovery, and EHR analysis. Challenges like model interpretability, data quality, and regulatory compliance remain, however.

Real-World Data in Biostatistics

Real-world data (RWD) derived from EHRs, patient registries, insurance claims, and wearable devices is increasingly being used to complement traditional clinical trial data. Unlike controlled studies, RWD provides insights into treatment effectiveness across diverse populations in real-world settings, supporting comparative effectiveness research, post-market drug surveillance, and long-term patient monitoring. However, data standardisation, selection bias, privacy, and security must be carefully managed to ensure integrity and ethical use of real-world evidence (RWE). When effectively integrated, RWE offers valuable perspectives on diverse patient demographics, long-term safety, and usage patterns beyond conventional clinical trials.

What Are the Applications of Biostatistics in Drug Discovery?

Biostatistics in drug discovery emphasises the exploration and validation of potential therapeutic targets before clinical evaluation. Statisticians at this stage often work in large, complex datasets such as high-throughput screening and omics data to identify promising compounds and refine them for further testing. Analytical approaches are flexible and exploratory, relying on advanced modelling, bioinformatics, and ML to sift through extensive laboratory or preclinical information. Although regulatory requirements are comparatively lighter than in clinical trials, sound experimental designs, data quality control, and careful interpretation remain essential. Ultimately, biostatistics ensures only the most promising and mechanistically sound drug candidates advance intro human trials.

Key Drug Discovery Applications

Target Identification and Validation
Statisticians analyse large-scale datasets to pinpoint potential drug targets, using statistical models to clarify gene-disease associations.

Preclinical Studies
Biostatistics guides experiment design and sample-size decisions for animal and cell-based models. By evaluating dose response, toxicity, and survival, researchers assess a drug's potential efficacy prior to clinical trials.

Biomarker Development
Statistical methods enable the identification and validation of biomarkers that predict drug response and disease progression, refining patient selection and advancing precision medicine.

Dose Optimisation and Pharmacokinetics (PK/PD Modelling)
PK/PD modelling examines how drugs are absorbed, distributed, metabolised, and excreted, clarifying the most effective dosing schedules.

Challenges and Future Trends in Biostatistics for Clinical Trials

As data complexity grows, biostatistics faces multiple challenges. Genomics, biomarkers, wearable devices, and RWE introduce high-dimensional data that can strain traditional models. Missing data and patient dropout, especially in decentralised trials, necessitate advanced imputation techniques and sensitivity analyses to reduce bias. Multiple comparisons across endpoints, interim analyses, and subgroups increase the risk of false positives, requiring sophisticated Type I error control methods. Meanwhile, regulatory agencies demand greater transparency to ensure reproducibility.

Looking ahead, Bayesian adaptive designs and model-based drug development (MBDD) will gain prominence for dynamic learning and adaptive decision-making. AI-driven methods will improve data processing, anomaly detection, and predictive modelling, although regulatory acceptance and explainability are still evolving concerns. The rise of hybrid trials combining RCTs with RWE will require innovative statistical techniques for casual inference and bias mitigation. Additionally, decentralised and virtual trials will push for new frameworks to handle missing data, patient adherence, and varied digital health inputs. Greater emphasis on transparency and reproducibility will remain a cornerstone of future biostatistical practice, ensuring clinical trials are robust, reliable, and trusted by regulators and the scientific community.

Conclusion

By ensuring reliability, accuracy, and ethical integrity, biostatistics enables data-driven innovation in patient care and public health. As the medical field increasingly embraces precision medicine and RWD, the role of biostatistics will continue to grow, ultimately shaping the future of healthcare innovation.

Quanticate’s statistical consultancy team delivers expert statistical support across the full clinical trial lifecycle, from protocol development and study design to complex analysis and regulatory submission. Our statisticians combine scientific rigour with flexible, data-driven methodologies to ensure high-quality, reliable results that meet global regulatory standards. Submit an RFI today to learn how we can enhance the efficiency, accuracy, and compliance of your clinical development programme.