Having designed a few randomized controlled trials, participated in others, and sat on a safety review board for another in my previous life, I thought this up-to-date scientific review of the methodology and its applications would be a good exercise for my old brain. I was not disappointed. Starting with the very early crude randomized trial to determine the best treatment for scurvy, Leigh reviews the many applications of randomized controlled trials in medicine, social sciences, public policy implementation, politics, and philanthropy with many surprising results.
I was not surprised to learn that, when subjected to good scientific study, many assumptions we never question are false. Knee surgery for a torn meniscus is no better than a sham operation. Neighbourhood Watch programs do not make neighbourhoods safer, and Scare Straight programs designed to frighten high risk youth out of a life of crime produce more criminals. Providing micro-finance loans to impoverished third world women does not help to lift them out of poverty. But over 1000 randomized controlled trials were used effectively to increase the educational value of Sesame Street programs for toddlers. As I stroll through a drug store, it strikes me that few of the thousands of products on display have been assessed in any meaningful scientific study, let alone the gold standard of a double blind randomized controlled trial. We have a long difficult task ahead of us if we are to replace anecdotes and endorsement by charismatic pushers with vested interests in selling useless or harmful products and treatments. In this regard, highly relevant to recent Ontario debates, I can find no randomized controlled trials of any treatments for autism that have yet reported results, although several are in progress. Why can we not wait for the results that show what, if anything, actually works before participating in street protests about the lack of funding for treatments that may not work at all? And the recently completed Apple Heart Study using Apple watches to diagnose cardiac arrhythmias enrolled 420,000 participants but no controls to determine the health impact if any. My hunch is that it probably just increased the anxiety of participants. This was a wasted opportunity, funded by Apple and Stanford.
It is in the realm of marketing and political persuasion that I have some concerns about the use of randomized controlled trials. When huge corporations with tons of data about all of us can use randomized highly targeted marketing trials to persuade us to buy products we don’t need, and cynical political operatives can use this powerful marketing tool to make us believe their lies, should there not be some controls imposed? But by whom?
Even ardent supporters of randomized controlled trials need to acknowledge some limitations to their use. A recent long insightful essay in The New Yorker bemoaned the lack of evidence of how to best wean patients off of various psychiatric drugs. As most trials of drugs are heavily reliant on funding from the pharmaceutical industry, it is not surprising that there are no randomized trials to determine how to stop taking prescribed drugs. And even in the early days of liver transplantation when the immediate mortality was 50 %, faced with a youth in the iCU in coma from untreatable chronic liver disease, it would have been unethical for me to use a coin toss to determine whether or nor to put her name on a list for transplantation. Some such decisions do not need to be informed by a randomized controlled trial. The real difficulty is to determine which ones do.
This book is a very useful primer for anyone interested in how good science can help inform decision-making in medicine, public policy implementation, education, politics and philanthropy. And an easy enjoyable read.
The Passionate Reader 