Beyond Belief: How Evidence Shows What Really Works

by Helen Pearson

The remarkable story of the global movement championing the idea that evidence, not opinions, should guide our decisions

Today, more and more people around the globe are using scientific evidence to figure out what works—in health, government and business as well as conservation, schools and parenting. This wasn’t always the case. This book tells the story of the evidence revolution—a worldwide movement that promotes evidence-based thinking—and shows how it can help us all, especially in an age of alternative facts.

For many years, most medical advice was based on doctors’ opinions and conventional wisdom, not solid science. Helen Pearson describes how evidence-based medicine swept the world in the 1990s—becoming the predominant form of medicine practiced today—and how the idea that evidence should guide decisions is quietly transforming a host of other fields as well. Do police patrols reduce crime? Do performance appraisals boost job performance? Do welfare programs help the poor? Do smaller classes aid learning? Do smartphones harm teenagers? At a time when science is under attack and questionable claims run rampant, Pearson underscores the importance of evidence in all facets of our lives, empowering each of us to sift fact from falsehood and misinformation from the truth.

Essential reading for the rational-minded, Beyond Belief is an engaging portrait of the mavericks, visionaries and rebels who share the simple belief that decisions based on evidence make the world a better place.

Genres: Science, Nonfiction

354 pages, Kindle Edition

First published April 28, 2026

Reviews

[Brian Clegg · Rating 4 out of 5]

Apparently it comes as a surprise to many that medicine was not particularly scientific until the end of the twentieth century (to be honest, it's no surprise to me - we had a GP who used homeopathy in the 90s). Instead it was based on anecdotal guidance - the kind of thing that appeared to work. Evidence-based medicine has since improved the field, trying where possible to base decisions on evidence, ideally based on randomised controlled trials.

The first part of Helen Pearson's book covers this well - though I think it's by far the least interesting part of what we discover. Instead what's truly fascinating is the rest of it, looking at a wide range of other fields where evidence was rarely properly used and that are only now starting to dip a toe in the water. These include social policy, policing, conservation, business and education.

The main part of the book gives us examples of how bad these areas have been in terms of basing decisions on what's always been done, or anecdotally is said to work without any evidence to back it up. Pearson is honest that in some cases it is near impossible to provide gold standard blinded randomised controlled trials, but emphasises the benefit of 'aluminium standard' approaches where the best approximation is made, and of systematic reviews when carried out in a timely fashion. This was a fascinating section with plenty of examples of things going well and badly, and a look at why it can be difficult to make the change.

Finally we get a shorter section labelled 'What to do' - this is a little confusing as it feels like it should be a 'what can I do about it' section, but this only applies to two of the chapters: children and parenting, and how to join the evidence revolution (technically an afterword). The first chapter 'A Crisis of Evidence: The Pandemic and Beyond' makes some interesting points about how evidence was handled in the pandemic, but spends quite a lot of time on applying the approach outside of Western countries, and on political difficulties in the US - which seem far removed from 'What to do' that applies to the reader. Though this part does not work as well as the main body of the book, because it seems more focused on high level concerns, it still has good material on the pandemic and parenting.

I just have two small complaints. One is the feeling we get primarily is that the evidence-based approach started with medicine. In reality, good science has always been evidence based, and there were fields of applied science such as engineering and industrial chemistry where the evidence-based approach was there long before medicine came close to being a scientifically-based activity. The other is that although some of the fields covered are very much those where the science element is social sciences, there is only a brief passing mention of the social sciences replication crisis in the evidence-based management section, yet a good number of the examples elsewhere are from pre-crisis dates. At the very least this should be underlined across the board.

However, that doesn't stop this being a highly readable and informative look at the way these areas that affect all our lives have traditionally ignored properly obtained evidence and relied on anecdote.

[Hannah DL · Rating 4 out of 5]

Really enjoyed this, going to be thinking about it for a while. 4.5

[Paul Sand · Rating 2 out of 5]

Recommended by Ronald Bailey at Reason! So I asked the Portsmouth (NH) Public Library to get a copy on that. And (sigh) I didn't like it as much as Ron did. But (hey) you might.

But it leaves you wondering right off the bat: how many babies did Dr. Benjamin Spock (indirectly) kill when diligent parents followed his "expert" advice to have their infants sleep on their tummies? That turned out to have a significant risk of SIDS, Sudden Infant Death Syndrome.

Good news: My sister and I survived our 1950s infancy, even given the occasional misguidance promulgated by that era's authorities. And our kids made it through the 80s OK, too, even though that tummy-sleeping advice persisted after that. Whew!

But mostly Helen Pearson's book is about "evidence-based" practices. Their earliest adoption was in medicine, and its use of Randomized Control Trials (RCTs) to determine the efficacy of medicines, procedures, and general advice. If there are no RCTs, or the existing ones are problematic (low sample sizes, etc.), a backup technique is "systematic review", where the literature is scoured for relevant studies, which are combined via statistical magic to give a reliable result.

Pearson goes on to show how the "evidence-based" technique has been applied in other areas: "social policies", policing, conservation, education, and management. The results there are more of a mixed bag. And Pearson's descriptions can get a little tedious at some points. I found the section on management to be extremely boring, with my eyes often wandering off the page, checking out what the cat is doing, or maybe looking at my phone… (She did, however, seem to imply that managers get taken in by fads promoted by charismatic hucksters. That matches my experience!)

At times, Pearson lets her ideology fly.

In discussing social policy, she claims Ronald Reagan, in his 1980 campaign, "told derogatory stories of the notional 'welfare queen,' referring to women who were supposedly claiming welfare fraudulently or even deliberating having children outside marriage in order to milk the system."

Reader, I researched this back in 2014. As far as anyone can tell, Reagan uttered the phrase once, in a 1976 radio address. And even then, he clearly attributed the phrase to someone else ("as she's now called"). He was referring to an actual (non-"notional") woman, known most commonly as "Linda Taylor". And his source was not the KKK, but Jet magazine.

Pearson also does a considerable amount of Trump-bashing, and a slightly less amount of RFKJr-bashing. This is to be expected, I suppose, from an editor of Nature, which dropped its usual neutrality to endorse Wheezy Joe in 2020 and Kamala in 2024. And (of course) she explicitly drops her "evidence-based" demands when it comes to climate change. The practice of "spewing greenhouse gases" simply "need[s] to stop". Period. Just shut up and do whatever the "experts" say.

I read a different book on RCTs back in 2012: Uncontrolled. I liked it better, and you might too.

[Suzanned99 · Rating 2 out of 5]

The author pooh-poohed decisions that were based on expertise and gave examples of successful scientific studies, although some wouldn't pass muster today (scurvy), and others turned out to be dumb luck (POWs were given yeast for some disease that they probably didn't have but the extra protein made the difference in their health). But then she touted meta-analysis as the ultimate study because it pulls results from multiple studies, and then never gives examples of where it actually worked. We're supposed to believe it's the best because common sense says it is. Surely there are examples? The author just asserts that these studies have saved many lives. In this theme of a book, she needs to prove it with examples.
Meta-analysis gets even murkier when one scientist asserts something based on screening studies with a certain level of reliability. But she seems to side with another scientist who thinks all studies should be considered. But then the book switches back to screening based on the reliability of tests. It doesn't make sense. Lastly, the discussion ends with meta-analysis is too complicated for doctors' limited time, so specialists should look at the studies and come up with "evidence-based" practices for doctors to blindly follow.
I was hoping for more understanding from this book.

[Wendelle · Rating 5 out of 5]

The Future Should be Evidence-Based
This book is about evidence-based methods of constructing conclusions and forming beliefs. We sometimes tend to form beliefs through anecdotes, intuition, friend-of-friend rumors, eminence-based methods or our own life experiences, but this book shows there's a better, test-driven way. It's the evidence-based method that draws on randomised controlled trials, that can later be then synthesized into systematic reviews of the scientific literature on that topic. This method has applications on every thorny issue, such as what works for policing (crime reduction), social intervention (poverty reduction), environment (ecological preservation), medicine (harm reduction or improvement of health outcomes), education (tutoring to help elevate struggling students) and parenting. The book traces the history of the development of nascent evidence-based movements in each of the aforementioned fields, through reference to key people in each field. This included Ian Chalmers, Archie Cochrane and David Sattler in medicine, Esther Duflo and Abhijit Banerjee in economics, and so on. This is a great publication that shines a light on evidence-based methods that have quietly revolutionized many fields that impact our lives.

[FT · Rating 4 out of 5]

So when the author concentrates on "How Evidence Shows What Really Works," this book is excellent. Definitely written for the general public--not experts. But still, even a physician would likely learn something from the policy, conservation, and maybe even policing chapters.

That being said, some of the chapters were noticeably less what the title inferred the book was about than others.

Medicine? Excellent. Policy, policing and education? Good, but not as extensive as the former. Parenting? A bit less.

One small thing that bothered me some. The author spends a lot of time talking about "eminence-based-medicine" and "we've always done it that way" arguments. Excellent! But then somehow she carves out an "it's ok" exception for indigenous peoples potentially doing this.

I mean if the whole idea is "evidence-based," that should be the best determination of how well a practice works. Not where a person happens to be from.

Now, I will grant that any proposal needs to be accepted and put into practice by the members living in that community. But to me, that seems like a different question. Maybe even the topic of another book (which this author definitely could write).

[James Veliky · Rating 5 out of 5]

“ Faced with the choice between changing one’s mind and proving that there is no need to do so, almost everyone gets busy on the proof.”
- John Kenneth Galbraith

“ It is true that we make many mistakes. But the biggest of them all is to be surprised by them: as if we had hopes of never making any.
-Thomas Merton

This work of scholarship by Helen Pearson, editor of Nature Magazine explores the fallacy of “ conventional wisdom” in the fields of medicine, police work, climate change, education and parenting. She offers the “randomized clinical trial” as the antidote to prove as near as possible what is true. So much of what we believe we have accepted on faith. Our faith and instincts do not always prove accurate. She is not afraid to state the problems and weaknesses of trying to prove long held beliefs. Finally, with all the evidence, we still have to make a decision to believe it.
Thank you Helen Pearson. You are great.

[Geoff Garnett · Rating 4 out of 5]

An engaging read, although the footnote break the flow, describing the evidence movement in a number of subjects. Ironically to make the work engaging it is the story of individual actors echoing eminent man (and it is mainly men) history. Nonetheless, it filled in some of the gaps in my knowledge of the organization and work involved in evidence based medicine and policy. The need to understand how policy and practice work and how to insert evidence into processes comes through.

[riti aggarwal · Rating 4 out of 5]

girl i really misunderstood and prejudged this book until i read it.... now the only question is if i should redo my paper on epidiemology a bit lol

[Maryann · Rating 4 out of 5]

I liked that Pearson focused on how research could inform decisions without getting too bogged down in statistical methodology.