Dr. Sameer Parpia is an Associate Professor, biostatistician and clinical trialist in the Departments of Oncology, and Health Research Methods, Evidence, & Impact (Formerly Clinical Epidemiology & Biostatistics) at McMaster University with interests and expertise in the design, conduct and analysis of clinical trials.

He is a senior biostatistician with the Ontario Clinical Oncology Group (OCOG), an academic clinical trials coordinating and methods unit that designs and conducts clinical trials in the areas of cancer, venous thromboembolism and surgery. In addition, he provides methodological and statistical support for other researchers, academic departments and organizations.

He is a Scientist at the Escarpment Cancer Research Institute and serves as the Director for the Canadian Institutes of Health Research funded Canadian Network For Statistical Training in Trials (CANSTAT) – an innovative platform to train and mentor (bio)statisticians in clinical trials.

Within the Health Research Methodology Program, he teaches courses in clinical trial methods and biostatistics.


PhD in Biostatistics (2014), McMaster University

MSc in Biostatistics (2007), Western University

BSc Co-op Mathematics & Statistics (2005), McMaster University



His research interests and and expertise are in design, analysis and reporting of clinical trials. He provides biostatistics and methodological leadership in clinical trials in and has served as the lead biostatistician for several multi-centre trials in various clinical areas.

He has an interest in oversight committees for clinical trials and has served on several data safety monitoring boards (DSMB) and trial steering committees.

In addition, he has interest in pilot and feasibilities studies, diagnostic studies, observational studies, systematic reviews and meta-analyses.

A full list of his publications can be found on can be found on PubMed or Google Scholar.

Select Publications

Omitting Radiotherapy after Breast-Conserving Surgery in Luminal A Breast Cancer (New England Journal of Medicine, 2023)

Impact of 18F-Labeled Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography Versus Conventional Staging in Patients With Locally Advanced Breast Cancer (Journal of Clinical Oncology, 2023)

Sensitivity analysis in clinical trials: three criteria for a valid sensitivity analysis (Eye, 2022)

Diagnosis of deep vein thrombosis with D-dimer adjusted to clinical probability: prospective diagnostic management study (British Medical Journal, 2022)

Perioperative optimization with nutritional supplements in patients undergoing gastrointestinal surgery for cancer: A randomized, placebo-controlled feasibility clinical trial (Surgery, 2022)

A simplified decision rule to rule out deep vein thrombosis using clinical assessment and D-dimer (Journal of Thrombosis & Haemostasis, 2021)

Clinical pre‐test probability adjusted versus age‐adjusted D‐dimer interpretation strategy for DVT diagnosis: A diagnostic individual patient data meta‐analysis (Journal of Thrombosis & Haemostasis, 2020)

Diagnosis of Pulmonary Embolism with d-Dimer Adjusted to Clinical Probability (New England Journal of Medicine, 2019)

Evaluation of a specialized oncology nursing supportive care intervention in newly diagnosed breast and colorectal cancer patients following surgery: a cluster randomized trial (Supportive Cancer Care, 2017)

D-dimer testing to select patients with a first unprovoked venous thromboembolism who can stop anticoagulant therapy: a cohort study (Annals of Internal Medicine, 2015)

Randomized trial of decongestive lymphatic therapy for the treatment of lymphedema in women with breast cancer (Journal of Clinical Oncology, 2013)

Interim cosmetic and toxicity results from RAPID: a randomized trial of accelerated partial breast irradiation using three-dimensional conformal external beam radiation therapy (Journal of Clinical Oncology, 2013)

Selective D-dimer testing for diagnosis of a first suspected episode of deep venous thrombosis: a randomized trial (Annals of Internal Medicine, 2013)

Warfarin dose assessment every 4 weeks versus every 12 weeks in patients with stable international normalized ratios: a randomized trial (Annals of Internal Medicine, 2011)

Competing events in patients with malignant disease who are at risk for recurrent venous thromboembolism (Contemporary Clinical Trials, 2011)

Long-term results of hypofractionated radiation therapy for breast cancer (New England Journal of Medicine, 2010)


Teaching and Supervision

He contributes to teaching biostatistics and clinical trials in the graduate Health Research Methodology Program (HRM) in the Department of Health Research Methods, Evidence, & Impact at McMaster University. Currently, he contributes to the following courses:

HRM 730 – Introduction to Research Methods for Randomized Controlled Trials
HRM 733 – Statistical and Methodological Issues in Randomized Clinical Trials
HRM 739 – Biostatistical Collaboration
HRM 723 – Regression Analysis
HRM 777 – Methods for Diagnostic and Prognostic Research

Student Supervision

Student supervision for graduate degrees in biostatistics and clinical epidemiology is done through the HRM program as well. For inquiries about student supervision, please complete this form.



He provides biostatistical consulting on health research projects where he works with researchers and organizations to design studies with the appropriate methodology and statistical analysis to answer the research question. Services and support include statistical design and analysis of phase I, phase II, and phase III randomized trials, diagnostic studies, pilot and feasibility studies, observational studies, and systematic reviews and meta-analysis. For collaboration or consultation, please complete this form.



Get in touch with me regarding collaboration, consultation, or graduate student supervision.