Screen detection and tumor growth rates. Cancers have different growth rates, which determine their potential to be detected by screening. Tumor A remains microscopic and undetectable by current technology (although more sensitive tests in the future might render it detectable). Tumor B eventually becomes detectable by screening (*), but its growth rate is so slow that it will not cause symptoms during the life of the individual; its detection will result in overdiagnosis. Tumor C is capable of metastasizing, but it grows slowly enough that it can be detected by screening (*); for some, this early detection will result in survival. Tumor D grows very quickly and therefore is usually not detected by screening. This will present as an interval cancer (i.e. detected clinically in the interval between screening examinations) and has a particularly poor prognosis. Note that of the four tumor types, only Tumor C has the potential to benefit from screening. Red dashed lines represent the natural history of a tumor in the absence of detection by screening. (Figure 1 from Gates, 2014).
A new stool DNA test was recently approved by the FDA for colon cancer screening. My first reaction was “Yay! I hope it’s good enough to replace all those unpleasant, expensive screening colonoscopies.” But of course, things are never that simple. I wanted to explain the new test for our readers; but before I could start writing, some other issues in cancer screening barged in and demanded to be included. They exemplify the dilemmas we face with every screening test. We have covered these issues before, but mainly in reference to mammography and prostate (PSA) screening. My article morphed into a CLT sandwich: colon, lung, and thyroid cancer screening.
The current issue of American Family Physician has a great article on cancer screening. It uses lucid graphics to illustrate lead time bias, length time bias, and overdiagnosis bias, as well the effect of varying tumor growth rates on screening success rates, all concepts that have been covered by Dr. Gorski here. Briefly, screening may do more harm than good if:
- It detects cancerous cells that never would have developed into invasive cancers or harmed the patient in any way;
- Early diagnosis and treatment decrease quality of life without reducing death rates; or
- The test falsely indicates cancer in patients who don’t have it or fails to indicate cancer in some who do. (more…)
One of my early forays into the world of pseudoscience was an investigation of “Vitamin O” (the O stands for oxygen). The story is hilarious; please click and read; I guarantee you won’t be able to read it without at least a chuckle. Vitamin O is still for sale; it’s even available on Amazon.com. You can read the manufacturer’s ridiculous rationalizations about the FTC’s and FDA’s regulatory actions against them and their bogus “research” here. In my article, I mentioned oxygen bars, which were popular at the time. I was under the impression that they had gone out of fashion since then. Alas, no.
Dr. Stephen Barrett of Quackwatch e-mailed me to suggest that I might want to write about the O2 Planet website. It calls itself “the largest oxygen bar and oxygen spa source on the planet.” I can’t decide whether to thank Dr. Barrett for steering me to a source of entertainment and making me laugh or curse him for making me suffer through a disgusting collection of pseudoscientific rubbish. Some of the company’s claims are listed on the graphic above. (more…)
A correspondent asked me to look into Airrosti because her employer’s insurance company had started covering it, and she was skeptical. She had tried to look up its effectiveness and safety record on the Internet and hadn’t found much. The information on their website didn’t tell me what I wanted to know, so I did a little digging. Like my correspondent, I am skeptical of their claims.
The name Airrosti stands for Applied Integration for the Rapid Recovery of Soft Tissue Injuries. One writer jokingly renamed it Owwwrosti because his first treatment was so excruciatingly painful. They say, “Wherever you hurt, we can help.” They claim to have special knowledge about the underlying cause of soft tissue injuries and pain problems and how to treat them; they claim they can resolve the problems of most of their patients in only 3 visits. The providers are chiropractors who have been trained by the company in their special methods…whatever they are. Their website is vague about what their modality actually consists of. I was able to piece together some of what they are doing from discussion groups and patient reports. There are plenty of testimonials, and the treatments are described as painful but effective. They offer quality 1-on-1 care for an entire hour, with detailed examination, hands-on soft tissue therapy, foam rolling, instruction in exercise and rehabilitation, and Kinesio Taping. Their main competitors are said to be the Graston technique and Gua Sha technique, and their treatment appears to be centered on myofascial release (MFR). In other words, it’s a mixed bag.
The Airrosti website, prominently featuring several bold claims. Click screenshot to see full size.
[Ed. Note: I realize that I normally post on Monday, but thanks to an R21 grant deadline tomorrow, I will not be able to post new material today (although you might have noticed some “familiar” material posted yesterday.) Harriet has graciously agreed to cover for me today, and we have a special guest post for you tomorrow. Fear not. I’ll soon be back. Trying to get the lab funded takes momentary precedence.]
In his new book The Myth of Mirror Neurons: The Real Neuroscience of Communication and Cognition , Gregory Hickok, a professor of cognitive science, challenges current conceptions about mirror neurons. He shows how a complex mythology arose and why it is unwarranted, how experimental results were misinterpreted and disconfirming evidence ignored, and how other interpretations might lead to better insights about how the brain works.
I couldn’t say it any better than Steven Pinker did on the jacket blurb:
Every now and again an idea from science escapes from the lab and takes on a life of its own as an explanation for all mysteries, a validation of our deepest yearnings, and irresistible bait for journalists and humanities scholars…Hickok puts an end to this monkey business by showing that mirror neurons do not, in fact, explain language, empathy, society, and world peace. But this is not a negative exposé—the reader of this book will learn a great deal of the contemporary sciences of language, mind, and brain, and will find that the reality is more exciting than the mythology. (more…)
Sandeep Jauhar wrote Doctored: The Disillusionment of an American Physician to express his frustration with the modern system of medical care in America. I found the book profoundly disturbing. If his experience is representative, I can understand why so many people have been criticizing doctors for only caring about money. His experience was so different from mine that I wondered if I had led a sheltered life as a military physician and was oblivious to what was going on in the civilian world. After further reflection, I think Jauhar is unduly pessimistic. Whatever the opposite of rose-colored glasses is, he’s wearing them.
His personal experience of medicine
Dr. Jauhar is a cardiologist who works in a large teaching hospital, where he had been hired to develop a program for patients with heart failure that would implement the most up-to-date medical knowledge and provide the best possible medical care. After long, grueling years of school, residency, and fellowship, he is elated to have finally finished his training and started a job where he can accomplish something good. But he soon sinks into despair. He is appalled by the realities of life as an attending physician, the many ways in which the “system” interferes with his efforts to provide the best care to patients, the unethical behavior of other doctors, and his inability to support his family.
The 2014 film Fed Up is an advocacy documentary. Its message:
- There is a worldwide epidemic of obesity.
- It is endangering our children.
- Increased sugar consumption is responsible.
- The food industry is responsible for our increased sugar consumption because it puts hidden sugar in processed foods, bombards us with advertising, favors profits over health, and lobbies against regulation.
- The government is responsible because it has failed to control the food industry.
The film has received mostly positive reviews and has been called the Inconvenient Truth of the health movement. It was written and directed by Stephanie Soechtig, whose earlier films attacked GMO foods and the bottled water industry, and narrated by Katie Couric, who “gave anti-vaccine ideas a shot” on her talk show in late 2013.
The film shows families struggling with childhood obesity and “experts” expressing their opinions. Their selection of “experts” is heavy on politicians and journalists and light on nutrition scientists.
Vaccination is arguably medicine’s greatest success. It has eradicated smallpox and has saved millions from death and suffering from a growing list of preventable diseases. It’s surprising that it has so many critics. Most of them are either not educated in medical science (like Jenny McCarthy) or are educated but prefer to reject science in favor of anecdotal experience (like Jay Gordon). Their arguments have been examined ad nauseum on this blog and elsewhere, and are easy to dismiss. But when I learned that an immunologist had written a book rejecting the whole idea of vaccination, I couldn’t dismiss it so easily. An expert in the field obviously knows more than I do about the relevant science; and if nothing else, she might have some valid criticisms of vaccines that I had overlooked. In 2012 Tetyana Obukhanych, PhD, published a short (53 page) book that is available in a Kindle edition: Vaccine Illusion: How Vaccination Compromises Our Natural Immunity and What We Can Do To Regain Our Health. I read the book hoping to learn something, and I did learn some things, but not anything that would make me question the current vaccine recommendations. I tried valiantly to understand her message; I think I succeeded. I’ll try to summarize what she is saying and explain why I think she got it wrong.
Typical example of a Vitamin K supplement.
Science is complicated. Simple concepts that appear at first to be obviously true or untrue usually turn out to be more nuanced than we thought. Newtonian physics was taken as “the truth” until we learned in the 20th century that it didn’t apply on cosmological or subatomic scales. Medicine and human physiology are more complicated than most people realize or want to believe. A case in point is the recent realization that vitamin K is not a single chemical compound, but a whole family of them, and that vitamin K2 has unique properties that vitamin K1 lacks.
Recently, there has been some interesting preclinical research on K2 that warrants further study to tease out its implications for human health, diet, and supplementation. There has also been a lot of hype that warrants taking its claims not with a grain but with a large bolus of salt. According to Canadian naturopath Kate Rhéaume-Bleue, author of Vitamin K2 and the Calcium Paradox:
- It could save your life
- It is missing from the modern diet
- It is the most important anti-aging nutrient for fighting wrinkles, Alzheimer’s, heart disease, osteoporosis and more
- It promotes straight, cavity-free teeth
- It is needed to get the benefits from calcium and vitamin D supplements; without it, those nutrients will increase the risk of heart attack and stroke
- It is the only vitamin known to prevent and reverse atherosclerosis
The old adage is still true: if something sounds too good to be true, it probably is. There is only weak evidence behind these strong claims. (more…)
The bad news: in a disturbing attempt to woo customers, some Australian pharmacists are offering in-store consultations with naturopaths. The good news: Australian skeptics and supporters of science have had a lot of recent successes in combatting quackery.
Non-Doc in a Box
In an article in the Australian magazine The Skeptic, Loretta Marron reports on naturopaths in pharmacies. You can read it here. Pharmacy customers who want natural treatment alternatives are referred by pharmacy staff to an in-house naturopathy clinic. The cost, $90 for a one-hour consultation, is often covered by insurance. You can even get a Loyalty Card to make your fifth consultation free. They claim to “correct underlying causative factors,” advise about stress, diet, how to promote your vitality and immune system, etc. And they help you make informed decisions about your health (informed by their brand of misinformation).
They offer disproven diagnostic methods like iridology, live blood analysis, and bio-energetic screening with bogus machines that they claim can detect everything from vitamin deficiencies and parasites to “spinal energy” and “vaccination disturbance.” Marron doesn’t describe the treatments they recommend, but we can assume they are offering the usual naturopathic remedies, including homeopathy, in lieu of the pharmaceuticals that are the reason for the pharmacy’s existence. (more…)
This cover picture is scientifically inaccurate. See explanation below.
José Jarimba believes that our bodies are physically molded into an asymmetric form by our mothers’ sleeping positions during pregnancy, that this has lifelong adverse impacts on health, and that shoe inserts can eliminate pain and other health problems by realigning the body. This is a silly untested hypothesis by a single individual. As such, it would be too minor to merit mention on SBM; but it is worth analyzing as a teaching opportunity. Jarimba attempts to bypass the scientific process; he provides a prime example of self-deception, confirmation bias, scientific ignorance, and the “Unpersuadables” I recently wrote about.
Much of alternative medicine originated with a “lone genius” who had an epiphany, thought he had discovered something no one had ever noticed before, extrapolated from a single observation to construct an elaborate theory that promised to explain all or most human ills, and began treating patients without any attempt to test his hypotheses using the scientific method. Some of them were uneducated laymen, others were scientifically trained medical doctors who should have known better. I wrote about one of them here, Dr. Batmanghelid, inventor of the Water Cure, who attributed a great variety of illnesses to dehydration after he thought he had cured a prisoner’s peptic ulcer disease by giving him a glass of water. Similar paths were followed by many others. Hahnemann invented homeopathy after he thought a malaria remedy gave him symptoms of malaria. Palmer invented chiropractic after he thought he had restored a man’s hearing by repositioning an out-of-place bone in his back. Nogier invented ear acupuncture after he imagined that the external ear looked sort of like a fetus. Shapiro invented EMDR after she noticed during a walk in a park that moving her eyes seemed to reduce the stress of disturbing memories. Bach invented Bach flower remedies after a walk in the country revealed his intuitive psychic connection to various plants. Jose Jarimba follows in their footsteps. (more…)