Just last month, after nearly three years of investigation, I published a book on a 22-year-old organization called the Cochrane Collaboration. The book’s subtitle, “Medicine’s Best Kept Secret,” was meant to be a little playful – as if one of the world’s largest organizations putting together systematic reviews of evidence around health care interventions could be a “secret.”
There are thousands of medical academics, researchers, clinicians and health policymakers who use Cochrane reviews every day in their work. The organization is also no secret to the 40,000 or so volunteers in over 130 countries who work under the banner of Cochrane, sifting, analyzing, and systematizing the body of evidence that underpins nearly every decision we make in healthcare. But alas, for the vast majority of patients and consumers of healthcare, the Cochrane Collaboration is a secret. I decided to write this book because I wanted to let the world in on the secret, which is vital both for the creators of health journalism as well as the consumers of health journalism.
The fact the Collaboration has become one of the world’s premier sources of independent and quality information about health care rests on a key principle: Individual studies to determine how well a health treatment works are not sufficient to make the best possible decisions. Higher up the evidence pyramid, you’ll find what the Collaboration produces: systematic reviews and meta-analyses which encompass all of the studies both published and unpublished on a particular question, studies that have been analyzed and statistically combined to create a summary of what is reliably reliable. When this is done in a methodologically sound and defensible way, what one hopes for is a consistent picture that points in the direction of benefit or harm related to that question.
I was approached by the organization in 2012 just prior to the 20th anniversary of the Collaboration and I wasn’t a stranger to its methods. I was periodically attending the annual meeting known as the Colloquium for at least a decade, and I was able to see — up close and personal — how these people operate. I was frankly inspired by a spirit of inquisitiveness and generosity that energizes their work. It was amazing to watch people who genuinely struggled with trying to find truth in health research, a process that’s messy, complicated, usually political, and always contentious, and motivated by an intense desire to turn large amounts of data into pictures that makes sense to doctors and to patients.
A recent example of the benefits of systematic reviews of evidence came across my plate when I saw the SPRINT (Systolic Blood Pressure Intervention) Trial. The study measured intensive blood pressure-lowering targets against “standard” blood pressure-lowering targets in people who had moderate hypertension. The trial was halted in September of this year and received a huge amount of media attention with the message that “lower is better.” In other words, those patients who are given the more intensive blood pressure-lowering treatment did better than those who were given the standard treatment. For me the story doesn’t end there, because I asked the next question: What does Cochrane say?
For me, a single study is a chapter in a story that has a past, a history, and a trajectory. A new study is rarely going to be “game changing,” because you need to know how the new evidence fits into the existing systematized body of evidence — and that’s what Cochranites do.
The Cochrane Hypertension Review group at the University of British Columbia in Vancouver has looked closely at the ‘lower is better’ issue. They were able to take the results of this trial, add it to the 10 existing trials of lower vs. standard blood pressure targets, to conclude the big picture does not change. Despite SPRINT’s breathless headlines around the world, the systematic evidence, which should be considered much more reliable, says that patients given the most intensive drug regimen to lower their blood pressure down to say 120 over 80 do not do any better than those who are given standard therapy. They don’t live longer or have fewer hospitalizations. A review of new evidence in its proper context delivers huge rewards to the millions of people around the world–and their doctors–when they decide how aggressively they will pursue lowering their blood pressures.
[Editor’s note: The Cochrane Group’s conclusions regarding standard vs. lower blood pressure targets are expected to be published in January 2016. The results mentioned in the preceding paragraph are based on a preliminary analysis discussed in a telephone interview with Jim Wright, coordinating editor for the Cochrane Hypertension Review Group. These results should be considered tentative pending publication of the full updated Cochrane review.]
The “secret” in my book’s subtitle also refers to this idea: that even though the Cochrane Collaboration, outside of the world of academia or research, is largely unknown, it has, over the years, been able to expose some very troubling truths about what we think we know or don’t know about medicine and health care treatments.
One of my interviewees in the book explained it this way: Think of the body of medical procedures, screening programs, and drug treatments as a pie. If you were to divide that pie into thirds, the first third would contain all of those procedures or treatments that we know are underpinned by quality medical research and for which we can truly say with some degree of certainty that they “work.” The second piece of pie would contain those things we routinely do but we don’t have strong evidence that the benefits exceed the harms, because they haven’t been well studied. The last third would contain many things that we do in medicine and health care where there is evidence that they do more harm than good, and we should stop doing those things.
So whether you’re a patient or a journalist, you might want to ask yourself, “Which third am I looking at?” whenever you are presented with a new piece of research or an expert assertion about a treatment, a medical device, a screening tool, or a new medication.
As journalists we are there to provide context, and there is no better “context” for health care evidence than the body of 5,000 reviews in the Cochrane Library. The abstracts and the plain language summaries of all of Cochrane reviews are available on their website. The in-depth reviews are made available free to journalists who belong to the Association of Healthcare Journalists. They’re also available at most university libraries.
It’s worth taking a look at and it’s worth getting to know what is becoming, less and less, Medicine’s Best Kept Secret.
Alan Cassels is a pharmaceutical policy researcher, a member of the HealthNewsReview team, and author of the just-published book, The Cochrane Collaboration: Medicine’s Best Kept Secret (Agio, 2015).