Beyond Belief
by Helen Pearson
Princeton University Press

While reading a nonfiction book, I often think, “This could be an essay.” It’s frustrating when a compelling argument is stretched to 100,000 words with filler anecdotes, unnecessary repetition, and irrelevant topics. We’ve all encountered such works.

However, Beyond Belief: How Evidence Shows What Actually Works is a refreshing exception. I found myself wishing it were longer. This insightful book delves into the seemingly dry subject of evidence-based policy, focusing on how experiments and trials apply across various fields such as international development, policing, and management. Despite the usual dense discussions of systematic reviews, Pearson crafted a highly readable and engaging narrative that I devoured in one weekend.

Author Helen Pearson serves as a journalist and senior editor for the magazine Nature. Having collaborated on some of my work and shared a pint in London’s pubs, I know her well.

Pearson introduces the concept of the “evidence revolution,” advocating for decision-making grounded in research rather than blind adherence to self-appointed experts or conventional wisdom. She begins with the medical field, where randomized controlled trials (RCTs) are employed to test new treatments scientifically.

In 1747, naval surgeon James Lind carried out pivotal early clinical trials aboard the warship Salisbury to combat the issue of sailors contracting scurvy. This debilitating condition results in swollen limbs, rotting gums, and eventual death. Lind’s experiment involved recruiting 12 men, grouping them, and providing different nutritional supplements. Those receiving citrus fruits like oranges and lemons recovered quickly. Although vitamin C wasn’t identified until the 20th century, its efficacy was evident, leading to its inclusion in sailors’ diets and a marked decrease in scurvy cases.

This episode of medical history showcases how far we’ve come. However, I was surprised to learn that the phrase “evidence-based medicine” is merely 35 years old. For much of the previous century, many medical decisions relied on the judgments of senior doctors, even though comparative trials had been conducted.

Pearson recounts the journey of Ian Chalmers, a 1970s doctor baffled by the inconsistent advice given by two different doctors for the same condition. Working alongside colleagues like Archie Cochrane, he endeavored to refine medical practice by generating systematic reviews and meta-analyses. By examining the published evidence across many scientific journals, they sought to determine what was reliable and what was not, culminating in the establishment of Cochrane Collaboration, which conducts systematic reviews on a myriad of topics.

While few rational individuals oppose the use of controlled trials and systematic reviews, Pearson shares horror stories of lavishly funded yet ineffective projects, such as ‘bat bridges’ that bats never utilized.

As the evidence revolution expands beyond medicine into social policy—concerning welfare payments, international development, policing, education, and conservation—it faces more complexity. Social policies involve human behavior, affected by free will and biases, making them harder to assess accurately. Pearson notes that interventions may work in one community but not in others due to significant differences.

I support the use of systematic reviews for such policies, but I wonder if Pearson and her interviewees are overestimating the benefits.

Numerous evidence-based policies have faltered, not due to the scientific validity of their approach but because core political challenges were overlooked. For instance, efforts like wolf reintroduction and child vaccination often fail not for lack of scientific backing but due to public distrust in authorities.

While Pearson highlights examples of evidence-based conservation practitioners collaborating with indigenous populations who possess invaluable insights, she tends to view sociopolitical barriers as minor obstacles rather than central issues. My experience with education reveals that failures stem not from a lack of evidence but from systemic challenges like overworked teachers and lack of engagement with current research.

The book Beyond Belief presents an intriguing exploration of attempts to personalize scientific methodologies within the intricate realm of human life, capturing both triumphs and setbacks. It would benefit from more depth on practical and sociopolitical barriers to evidence-driven decision-making—perhaps that could be the focus of her next work.

Michael Marshall is a science writer based in Devon, UK.

3 More Great Books on Evidence Tracking

Bad Science
by Ben Goldacre

In this enlightening narrative, doctor, author, and broadcaster Ben Goldacre uncovers how the media often propagates misinformation as truth while even simple checks can reveal the actual facts.

The Whole Golem: What You Need to Know About Technology
by Harry Collins and Trevor Pinch

This book examines the challenges faced by the scientific method in wrestling with the complexities and uncertainties inherent in real-world phenomena.

The Failure of Our Government
by Anthony King and Ivor Crewe

This engrossing and often humorous account of governmental blunders highlights why British politics can be so mismanaged. The lack of evidence is just one of many systemic issues.