About Zaher
- Statistical analysis of clinical trials (Phases I-IV)
- Advanced survival analysis: Kaplan-Meier, Cox models, competing risks
- Real-world data (RWD/RWE) exploitation
- Statistical validation of artificial intelligence models in health
- Predictive modeling and explainable machine learning
- Development of reproducible pipelines (R, Python, SAS)
- Scientific writing, protocols, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)
- Health-economic studies and budget impact analyses
French
Native or bilingual
English
Fluent
Experience
- Owkin FranceSenior Biostatistician | AI in Healthcare & Oncology | MedTech & BiotechBIOTECHApril 2025 - December 2025 (8 months)Paris, FranceWorked as a freelance senior biostatistician on multiple high-impact projects at Owkin, an AI-driven biotech company, contributing to clinical validation, analytical performance assessment, statistical modeling, and health-economic strategy for AI-based diagnostic and prognostic tools in oncology. Close collaboration with data science, medical, regulatory and product teams to ensure scientific robustness, regulatory readiness, and business relevance.
- Clinical Statistics & Survival Analysis: Led advanced survival analyses on oncology cohorts: Kaplan–Meier estimation, Cox proportional hazards models, Hazard Ratios (HR), 95% confidence intervals, Wald & log-rank tests, Clinical validation of AI-based prognostic risk scores (low-risk vs high-risk stratification), Analysis of long-term clinical endpoints (dRFI, IDFS at 5 and 10 years), Interpretation of results for clinical study reports (CSR) and scientific communication, Contribution to scientific manuscripts and publication-ready analyses.
- Analytical Validation & AI Model Performance: Statistical validation of AI models in digital pathology, Analytical performance studies including: Within-laboratory precision (WLP), Between-laboratory precision (BLP), Method comparison studies (e.g. H&E vs HES): Deming regression,Bias analysis,Bland–Altman plots, Definition of acceptance criteria, sample size estimation and validation protocols.
- Statistical Programming & Reproducibility:Development of robust statistical pipelines in R,Automated analyses, reusable functions, and standardized reporting,Setup and maintenance of Git repositories to ensure:Code traceability,Version control,Full reproducibility, Clear documentation for internal knowledge transfer.
- Health Economics, Pricing & Reimbursement Modeling: Design of economic models for AI medical devices:Fee-for-Service vs Bundled Payment systems,Cost-effectiveness and budget impact analysis.
- Scientific peer reviewer – Journal of the American Statistical Association (JASA).Senior Statistical Expert & Peer ReviewerRESEARCHOctober 2025 - Today (8 months)Paris, FranceResearch article proposing a novel graph-theoretic, distribution-free test of randomness based on random interval graphs. The method detects complex dependencies (nonlinear, heteroskedastic, chaotic) beyond standard correlation tests and shows strong performance in simulations and real data applications.
- Wiley – Cancer Medicine JournalScientific Peer Reviewer – Oncology (Cancer Medicine, Wiley)RESEARCHApril 2025 - Today (1 year and 2 months)Londres, United KingdomProject: "Colorectal Peritoneal Metastasis Incidence and Survival in the United States: A SEER Retrospective Cohort Study".Role: Biostatistician / Epidemiology & Survival Analysis ConsultantDomain: Oncology, Real-World Evidence (RWE), Population-Based Studies
- Data Source: SEER (Surveillance, Epidemiology, and End Results – US National Cancer Institute)
Tools: R, Survival Analysis, Cox Models, Kaplan–Meier, Epidemiological Methods.Led the biostatistical and epidemiological analysis of a large population-based retrospective cohort study using the SEER database, aiming to evaluate:- The incidence of colorectal cancer with peritoneal metastasis
- Overall survival and survival determinants in affected patients
- Prognostic factors influencing outcomes in a real-world US population
This project provides real-world evidence to support clinical understanding and research in advanced colorectal cancer.Epidemiological & Statistical Analyses:- Construction and cleaning of a large retrospective cohort from SEER
- Estimation of incidence rates and temporal trends of peritoneal metastasis
- Descriptive epidemiology: Age, sex, tumor characteristics
- Disease stage and metastatic patterns
- Survival analyses: Kaplan–Meier survival curves Median survival,Long-term survival probabilities,Multivariable Cox proportional hazards modeling to identify: Independent prognostic factors, Risk-adjusted survival differences.
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Education
- PhD in BiostatisticsUniversité de Paris2008Risque d'émergence d'un pathologie dans une population
- Master in BiostatisticsUniversité de Montpellier, INRA, ENSA2005Modèles et outils de la biostatistique
Certifications
- py4e101x: Programming for Everybody (Getting Started with Python)University of Michigan2025
- PY0220EN: Python for Data Science ProjectIBM2025