A long time ago I read a study about what makes a good doctor. Some things you might think were important, like grades in medical school, were irrelevant. What correlated the best was the number of medical journals a doctor read. I don’t know whether that means good doctors read more journals or reading more journals makes a better doctor.
One thing I do know is that most of us could learn better journal-reading skills. When I was a busy clinician, I did what I suspect many busy clinicians do: I let the journals pile up for a while, then tackled a stack when I got motivated. I would skim the table of contents to pick out articles that I wanted to read, then I would read the abstracts of those articles. If the abstract interested me, I would read the discussion section of the article. If I was still interested, I might go back and read the entire article. But until after I retired, I never really developed the skills to evaluate the quality of the study.
I knew enough not to jump on the bandwagon the first time something was reported, because I had seen promising treatments bite the dust with further testing. But I really wasn’t aware of all the things that can go wrong in a study, and I didn’t know what to look for to decide if the results were really credible. I’m not an academic; I thought the authors knew a lot more than I did, and I trusted them to a degree that was not warranted. (more…)
For years postmenopausal women were told that estrogen was safe. Now they’re being told that estrogen is dangerous. Women are confused. The media haven’t helped; they’ve only increased the confusion and created some myths. Alternative medicine offers the option of herbal remedies they say are safer than estrogen. Suzanne Somers says all of us (even men!) should be taking bioidentical hormones and adjusting our own doses according to how we feel. What’s a woman to do? What does the science really say?
Before the Women’s Health Initiative (WHI) of 2002, there were two main reasons for prescribing hormone replacement therapy (HRT): it relieved perimenopausal symptoms like hot flashes, and it helped prevent osteoporosis and fractures. There was good reason to believe that estrogen might also reduce the risk of heart attacks, but very few doctors (if any) ever prescribed it for the sole purpose of reducing heart risks. And doctors were always aware that estrogen and progestins were powerful drugs and were not risk-free.
There was a time in the mid-20th century when estrogen was thought to be a fountain of youth and women were encouraged to start taking it at menopause and continue for the rest of their lives. That attitude quickly changed as we realized these hormones were associated with blood clots, strokes, and increased rates of some cancers. We also learned that unopposed estrogen caused uterine cancer, and women who still had their uterus had to take progestins along with their estrogen. (more…)
A recent meta-analysis of the most commonly prescribed antidepressant drugs raises some very important questions for science-based medicine. The study: Initial Severity and Antidepressant Benefits: A Meta-Analysis of Data Submitted to the Food and Drug Administration, was conducted by Irving Kirsch and colleagues, who reviewed clinical trials of six antidepressants (fluoxetine, venlafaxine, nefazodone, paroxetine, sertraline, and citalopram). They looked at all studies submitted to the FDA prior to approval, whether published or unpublished. They found:
Drug–placebo differences in antidepressant efficacy increase as a function of baseline severity, but are relatively small even for severely depressed patients. The relationship between initial severity and antidepressant efficacy is attributable to decreased responsiveness to placebo among very severely depressed patients, rather than to increased responsiveness to medication.
The press has largely reported this study as showing that “antidepressants don’t work” but the full story is more complex. This analysis certainly has important implications for how we should view the body of evidence for these antidepressants. It also illuminates the possible role of publication bias in the body of scientific literature – something that has far ranging implications for science-based medicine.
A foolish consistency is the hobgoblin of little minds, adored by little statesmen and philosophers and divines.
— Ralph Waldo Emerson (1803–1882)
It is odd isn’t it? Large numbers of quality studies published in the best peer review journals consistently showing the same or similar effect and no contradictory studies. Despite the emphasis on evidence-based medicine, the entire literature is dismissed as not relevant because personal experience suggests that the studies are wrong.
Curiouser and Curiouser. Coherent arguments as to the validity and scope of the literature are met with denial but never a critique of the primary literature. The facts of the research are never argued. The only argument is personal experience or blanket denial. Despite the published literature, practice continues the same, untouched by the facts.
How can practitioners routinely deny a preponderance of evidenced-based medicine? What is a doc who believes in the primacy of evidenced-based practice to do but roll their eyes and think, as Bugs Bunny so memorably said, “What a maroon”.
I’m talking about acupuncture? Homeopathy? Therapeutic touch?
The Food and Drug Administration (FDA) is proposing a very interesting loosening of their regulations of pharmaceutical company marketing. The pros and cons of the proposed changes present an interesting dilemma, with legitimate points on both sides.
When the FDA approves a drug it is approved for a very specific medical indication. I have long thought that FDA approved indications for drugs were too narrow and restricting. For example, most anti-seizure medications are initially approved not for seizures but only for certain types of seizures – for example for adjunctive therapy (meaning it is meant to be added to another drug rather than used alone) for focal onset seizures (and not against primary generalized seizures – or ones that begin all over the brain at once).
Once approved physicians are free to use drugs as they see fit. If evidence shows that a new seizure medication is effective as first line treatment, then it is ethical good medicine to use it that way, even if it is not FDA approved for that use (this is called off-label use). FDA approved is not equivalent to science-based.
There is an organization that calls itself The International Network of Cholesterol Skeptics (THINCS). Its members “thinc” they are smarter than the average doctor. They “thinc” that cholesterol has nothing to do with cardiovascular disease and that we have been deluded into waging a “cholesterol campaign” for which the scientific evidence is non-existent. They say, “What we all oppose is that animal fat and high cholesterol play a role.” I find even the wording of this statement problematical: one does not usually hear scientists “opposing” matters of fact or non-fact. They go on to say, “The aim with this website is to inform our colleagues and the public that this idea is not supported by scientific evidence; in fact, for many years a huge number of scientific studies have directly contradicted it.”
They tell us about those contradicting studies; but they don’t tell us about the flaws in those studies, they misrepresent some of the results, and they don’t tell us about the many good studies that support the cholesterol/heart link. The issue is a complex one, and it is easy to find studies to support any claim. Good science is about weighing all the evidence pro and con before reaching a conclusion. As far as I can see, these folks have cherry-picked the literature to support an agenda. They seem to have a vendetta against statin drugs in particular.
The website solicits complaints of adverse effects from statin drugs. It features a petition to the WHO that you can sign requesting an investigation of statin side effects. It alleges that lowering cholesterol endangers the elderly. It provides “what the medical journals and newspapers won’t let you hear” – letters and papers that have been rejected for publication. It lists books, published papers and talks by its members. It solicits financial contributions to the cause.
This movement seems to have started with Uffe Ravnskov’s book The Cholesterol Myths, published in Swedish in 1991 and in English in 2000. That book has been severely criticized, for instance in The Skeptic’s Dictionary , where Bob Carroll points out some of the distortions and deceptive techniques found in the cholesterol skeptics’ arguments. A typical claim: “Cholesterol is highly protective against cancer, infection and atherosclerosis” and “high TC [total cholesterol] and LDL levels are beneficial at all ages.” These statements are not only false, they are potentially dangerous to the health of those who believe them. (more…)
The name of this blog is Science-Based Medicine. The reason it is so called is because we, the bloggers who will be contributing, believe that “the best method for determining which interventions and health products are safe and effective is, without question, good science.” Sadly, one of the people who best represented this very sort of philosophy, Dr. Judah Folkman (1933-2008), has died. Dr. Folkman was the epitome of everything that a science-based surgeon or physician should be, and he was first among my scientific and surgical heroes.
A recent web feature produced by the New York Times tells the story of Chris Kilham, “The Medicine Hunter.” Specifically it recounts his thoughts on the use of maca, a root native to South America, “said to have energy and libido enhancing properties,” according to the piece. The brief piece reflects the current attitudes popular in the public and promoted by mainstream media reflecting a false dichotomy between medicinal plants and pharmaceuticals. This false dichotomy is extremely counterproductive and ultimately harmful to consumers.
Kilham represents this false dichotomy when he says:
“My goal is to have more people using safe, effective, proven, healthful herbs, and fewer people using toxic, overly expensive, marginally effective, potentially lethal pharmaceutical drugs.”
There are many unwarranted assumptions in this statement. It seems to be implying that herbs are inherently more safe, less toxic, and more healthful than pharmaceuticals. It also assumes that there is a real difference between the two. Therefore Kilham seems to be saying something meaningful when he is actually just reflecting biased assumptions. This is made clear if we simply reverse his statement. Most people, for example, would agree if I said that “My goal is to have more people using safe, effective, proven, healthful pharmaceuticals, and fewer people using toxic, overly expensive, marginally effective, potentially lethal herbs.”