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Correlation vs R Squared Explained This Is Why It Matters

This Is Why with Dr. Busti

This Is Why with Dr. Busti
Correlation vs R Squared Explained This Is Why It Matters
May 13, 2026
Anthony Busti, MD, PharmD, MSc, FNLA, FAHA

In this episode on This Is Why, Dr. Busti breaks down one of the most commonly misunderstood biostatistics concepts: correlation vs coefficient of determination. You’ll learn how to interpret the correlation coefficient (r), what it actually tells you about relationships between variables, and why it does NOT imply causation.


Then we connect that foundation to R² (coefficient of determination) — and This Is Why it’s critical for understanding how much variability one variable explains in another. Through clinical context and practical examples, you’ll see how these concepts apply to real-world decision-making, not just test questions.


If you’ve ever confused association with causation or struggled to interpret R values, this episode will help you connect the “why” behind the numbers.


Topics Covered:

- Correlation coefficient (r) definition

- Strength vs direction of relationships

- Why correlation does NOT equal causation

- Confounding variables explained

- Interpreting R values clinically

- Coefficient of determination (R²)

- Variability explained between variables

- Clinical example: calories and weight

- Relationship vs prediction in statistics


The goal = make medical education easy and clinically relevant.


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#correlation coefficient #R squared #biostatistics explained #coefficient of determination #Dr Busti


Speaker: 

Anthony Busti, MD, PharmD, MSc, FAHA, FNLA, is a licensed healthcare professional and medical educator with over 30 years of experience in clinical practice and academic teaching. He has trained and practiced as a nurse, pharmacist, and physician, bringing a uniquely comprehensive perspective to patient care and medical education. 

Dr. Busti is dedicated to advancing evidence-based medicine and helping clinicians understand the underlying “why” behind clinical decisions to improve patient outcomes. 


About This Channel: 

This content is created by Anthony Busti, MD, PharmD, MSc, FAHA, FNLA, a board-certified physician with training at Johns Hopkins School of Medicine and University of Oxford and a medical educator for healthcare professionals and students. All material is based on current medical literature and evidence-based guidelines that align with principles of evidence-based medicine (EBM) and Evidence-Based Healthcare (EBHC). 


Disclaimer: 

This content is for educational purposes only and is not medical advice. It does not replace individualized evaluation, diagnosis, or treatment. Always seek the advice of a qualified health provider with questions about a medical condition and never delay care because of educational content.