Second Edition — Oxford University Press

Epidemiology Matters

An introduction to methodological foundations. Seven steps toward an epidemiology of consequence.

Katherine M. Keyes · Mohammed Abba-Aji · Sandro Galea

100 Farrlandians — 20 with disease
Oxford University Press

For Students

Learn epidemiology by doing. Manipulate populations, observe associations, introduce bias, and see what happens. No formulas required to start — just curiosity.

For Instructors

Replace a lecture with a live demonstration. Use preset scenarios to show confounding, Simpson's paradox, or selection bias in real time. Assign interactive exercises tied to each chapter.

For Everyone

Epidemiology shapes policy, headlines, and daily life. Understand how we know what causes disease — and why it matters who we study and how we study them.

The Framework
Seven Steps for an Epidemiology of Consequence

The book organizes epidemiologic thinking around seven foundational steps. Each builds on the last. Together, they constitute a complete framework for studies that matter.

1
Define the population
2
Measure exposures & outcomes
3
Take a sample
4
Estimate associations
5
Evaluate causality
6
Assess interaction
7
Assess external validity
Interactive Companion
Learn by Doing

Each tool maps directly to the book. Use them in class, assign them as exercises, or explore on your own. The print edition includes QR codes linking to each module.

New in the Second Edition
Consequence Boxes

Each chapter connects a methodological choice to a question of social responsibility.

◆ Chapter 3: Measurement

How we define a health indicator determines who counts as a case. Who counts determines what risk factors we find. What we find determines what gets funded.

Consider depression. A clinical interview identifies fewer cases than a screening tool. Those missed are disproportionately people without access to clinical settings. The measurement choice is not neutral.

When you choose a measure, ask: whose health does this make visible, and whose does it obscure?

Launching Fall 2028

The Farrlandia Challenge

An inter-school competition for public health students. Investigate an outbreak in Farrlandia. Identify causes. Propose interventions. Compete against teams from schools across the country.

4 Rounds, 4 WeeksEach round follows the seven-step framework: define, investigate, challenge, intervene.
Real ToolsTeams use the platform's interactive modules to analyze the Farrlandia dataset.
Free to EnterOpen to any team of 3–5 students enrolled in a public health program.
Consequentialist ScoringJudged on rigor, population impact, communication, and creativity.
Get Notified When Registration Opens
The Authors
Keyes, Abba-Aji, and Galea

Stay Updated

Get notified when new tools launch, when the Farrlandia Challenge opens, and when the second edition is available.