How often does the Evidence in EBM turn on statistical subtleties?

A few years ago I posted a piece about the effects of antioxidants on GI tract cancers.There was a reported small increase in Relative Risk (1.06) if one used a fixed effects statistical model but no increase if one used a random effects statistical model analysis.

Here the truth seemed to turn on the choice of statistical method used. How robust could the truth be when it depends on choices made by statisticians and importantly when experts disagree on the choice which was the case quoted above? For a critical reader to decide for himself in a rational way it seems he would have to be fairly conversant in the vagaries of regression analysis and analysis of variance which are the areas where these two competing statistical models live.

I have read that the fixed effect model in general is the one more commonly used and it is the one with lower standard errors and hence more power. I have read that in regard to meta-analysis the fixed effect model is appropriate when the data appear homogeneous and the random effects model when the data are heterogeneous. Then we run up against tests for heterogeneity in regard to which no one should be surprise if statisticians may differ as to the correct way to do that. It seems to me if I writing a paper and wanted it published and since positive studies are more likely to see the light of day in print I would want to use the more powerful fixed effects model.


It seems the deeper you plunge into the analysis of the data the less certain you may become regarding the robustness of the conclusion.But truth does not really turn on the basis of the choice of statistical technique for one meta-analysis.The results of any one study-even if that study is a meta-analysis-should not decide the issue.Prior context and biological plausibility must be taken into account.

How to survive under socialized medicine

Here is a quote which to me seems may have high titer of deep insight.(my bolding)

"In many areas of medicine, particularly those related to especially politicized areas like CVD and other "life-style" diseases, government-franchised practitioners are often dangerously ignorant of essential facts. Remember that the worst aspect of socialist medicine is that medicine as a rational science is epistemologically destroyed by eliminating the role of the doctor as a sovereign, independently thinking, professional. "

H/T to Dr. Paul Hsieh in his blog "We Stand Firm" who in turn found it in essay entitled "How to Survive under Socialized Medicine" which was re-published in another blog (ReasonPharm) which in turn credited it to a facebook entry by some one named Christian W. (Please excuse the rather lengthy attribution but I did not want to slight the person who seems to be the actual author.)

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The division of internist into hospitalist and "officist" and its demise.

It is the 20th  anniversary of the birth of the hospitalist.A recent article describes what was presented as a fairly widespread feeling among hospitalists  of "not getting no respect. ".

Some of the doctors interviewed  spoke of the hospitalist being a gopher for various attending physicians,a clerk and paper work finisher for numerous physicians and thought of more or less as a intern or junior resident and one who often seemed not worthy of a return phone call.The duties of the hospitalist when I was briefly  in the hospital last year with a pulmonary embolus seemed to fit that pattern. A very pleasant young physician mainly ushered the consulting cardiologist and pulmonary doc in and wrapped up the paper work as both of the consultants made the real decisions regarding testing and treatment. A colleague of mine who attended at that hospital said he made the decisions regarding patients he admitted while the hospitalist was useful in relieving him of paperwork. I realize that the above description does not apply to the situation of all hospitalists.

While the officist has become barely distinguishable from the FP or GP or even NP, the hospitalist , at least in some settings seems to have devolved into a junior  house officer while the real management of the critically ill fall to the cardiologist, the pulmonologist and the intensivist.


In the 1970s and 80s in our internal medicine  practice it was routine for GPs ( they were not FPs at the time) to  refer complicated,sick patients to our groups. ( It seemed to more often than not happen late on Friday afternoons. The physician to whom the referral was made would personally  care for the patient in the hospital  often aided by his  internist specialists partners.)

The sequence was that the patient or referring physician would call the physician in our group -if he was not on call one of the partners would  admit the patient to the hospital and attend to him calling on other partner subspecialists as the situation warranted. Now the patient calls ,for example after hours and the recorded message advises the patient to go to the ER. He is seen by the ER doctor who may admit the patient and the hospitalist would see the patient and consult as needed various specialists. The internist, assuming the patient had one, would often learn of the event when the patient was discharged back to the internist who had nothing to do with his treatment and may or may not have received a copy of the discharge summary.

In describing that archaic situation to young house staff  I would feel like describing the quaint rotary phone that I used when growing up in the 50s.

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James Gailbraith combines a belief in perpetual motion machine with believe in there IS a free lunch in his economic advice

Dr. James Galbraith is the son of John Kenneth Galbraith and here the apple falls very close to the tree. See here for his  thoughts published in the Nation. Here is discussion of those comments as formulated by Dr.Paul Hsieh and published on line at Pajamamedia.com blog.

Here are the major points as Dr. Hsieh summarizes them:

1. The political push to reduce government deficits is economically misguided, based on an irrational “phobia” of deficits.
2. If we want economic growth, we need more spending. Only banks and governments can stimulate spending because (in his words): “Governments and banks are the two entities with the power to create something from nothing.”
3. We shouldn’t worry about the alleged impending bankruptcy of Social Security or Medicare — or of the U.S. government itself. Why? Because the government is the source of money and therefore can’t run out.
4. Government debt is not really a “burden on future generations,” because it never has to be repaid. Each generation can just pass that debt onto the next generation, so there’s no problem.

Think about what he said. Governments and banks can create something from nothing. Yes, I know that the government can "print money" and that banks create money in the fractional reserve banking system but you can't fool all of the people all of the time. The government and banks in Greece seem to have not understood that universal principle as they have made nothing out of something as they made tried to make something out of nothing Apparently the government in Greece has not consulted with Dr. Galbraith as they seemingly have run out of money. His perpetual motion money making machine is that you just keep rolling over debt which was the something that governments made out of nothing and there is no problem. So why did the Germans and the EU have to bail out Greece? Why could not the government just continued to make something from nothing?Why did we see hyper-inflation in Germany? Why are Not all countries made prosperous by this simple technique print more money and spend it.

Before Obamacare it was other people's money effect -Afterwards more so

 When something is being payed for with other people's money, more will purchased. This is also true if you merely think someone else is paying for it, as in the situation that exists with employer paid health care insurance.

Quoting myself from 2006:

Medical care came to be "managed " by the managed care sector because of the concept of "other people's money". To a large degree individuals pay for only a portion of their health care the remainder paid by either employers or the government. There was not much fuss made by these other people until the costs of health care rose to some threshold above which employers and other third party payers including CMS thought costs were getting out of hand. Then entered cost containment via the various cost savings actions of managed care.

The effect on the traditional fiduciary duties of physicians to patients by the duties of the for-profit corporation vis-a -vis its shareholders is the root cause of many ethical problems generated by managed care. Basically the HMO and third party payers generally strive to make money or save it and they introduce mechanisms to control physician behavior to that end even if that control involves abrogation of the fundamental duty of the doctor to place the patient well being and interests first. The efforts of the third parties in that regard weaken the physician-patient relationship and damage the trust element in the relationship.Ethical cover for this abrogation was provided by the introduction and unfortunate widespread acceptance by medical professionals organizations of the "New Professionalism" which alleged a physician's duty to society to be a good steward of society resources must somehow be balanced against the physician's duty to the patient.

With Obamacare, more people will be trying to spend other people's money.The biggest other people is CMS who along with HHS will have mandates to control costs. Mix in the decreasing number of primary care doctors to the number of patients seeking care with HHS/CMS moving to decrease health care providers reimbursements and you have a situation in which patient need more than ever an advocate. But patient advocacy will be not longer be the prime directive but merely a factor to be weighed against the imperative to be a steward of society's scare medical resource to the extent that physicians actually internalize the bogus arguments of the New Professionalism.

What is the evidence that prolonged endurance execise damages the conduction system of the heart.

In 1985, RJ Northcutt studied 20 males endurance athletes that were recruited from a Scottish Harrier's club. All were  older than 45 years and ran for 25 miles per week  or more. Stress testing and 48 hour Holter type monitoring were done.. He found that 9 had heart  rates less than 35 beats per minutes,6 had a prolonged PR interval, 4 had Mobitz type ii heart block and three with complete heart block one of whom had a pacemaker implanted. With exercise all of the various blocks disappeared.

Northcott with co-author Stuart Hood (1,2) studied 19 of the 20 subjects  twelve years later.Two of the group had pacemaker implantation in the interval, one for complete heart block with atrial fibrillation and the other for asystolic intervals up to 15 seconds. None of the others had any "bradycardic problems". 7 of the 20 in 1985 has systolic pauses greater than 2 seconds and 5 of those had none on follow-up. The other two had decreased the intensity of their running. ( not clear from the article if those 2 had pauses or not) Quoting the authors: "Our finding nonetheless suggest that clinically significant bradycardia symptoms are a real but rare potential complication of lifetime endurance exercise."

Baldesberger et al  (3) studied 62 former professional cyclists who had long since (over thirty years) retired from active competition.Two had pacemaker implantation. None had complete RBBB or LBBB and two had EKG pattern of left anterior hemiblock.None had second degree heart block. Six had "sinus node disease which the authors defined as heart rate less than 40 beats per minute.

Andersen's 2013 article (4) is often quoted in support of the argument that there is an increased risk of atrial fibrillation in endurance athletes but it also has data on the risk of  "bradyarrhythmias".The authors studied the records of over 52 thousand participants in a 90 km cross country race in Sweden  (the Vasaloppet). They then compared those who raced more (five or more races) with those who only did one race and compared the faster skiers with the slower. The  Hazard ratio (HR) for atrial fibrillation was 1.2 (0.93-155) while the HR for bradyarrhythmias was 1.85 (0.97--3.54). When comparing those who did more races with those who did only  one they reported a HR for AF of 1.29 (1.04-1.61 and a HR for bradyarrhythmias 2.10 (1.28-3.47).The bradyarrrythmis were mainly type ii heart block but the ICD s codes used did not enable the investigators to separate type 1 and 2 second degree block, an important distinction as Wenckeback is usually considered much less  serious that type 2 second degree block. No mention was made on any one requiring a pacemaker. The rhythm outcome endpoints were obtained from hospital records those race finishers hospitalized with rhythm disturbances.

Comment.This is a very "coarse grain" study.All that was known about the subjects was the race numbers and times ,ICD codes of those hospitalized with arrhythmias, and their age, education and occupational status. How much they exercised outside of this race and other pertinent health factors that could influence the outcome ( BP,diabetes,obesity,height,smoking history,alcohol use) were not known and the various hazard ratios were not all statistically significant. Incidentally,  the HR for atrial fibrillation were much lower than the five times increased risk often quoted for AF in several case control studies.



1.Northcote R. et al. Electrocardiographic findings in male veteran endurance athletes. Br Heart J. 1989, 61: 155-160

2.Hood S and Northcote,R Cardiac Assessment of veteran endurance athletes;a 12 year follow up study. Br J Sport Med, 1999, 33: 239-243

3.Baldesberger S,  et al Sinus Node disease and arrhythmias in the long term followup of former professional cyclists. Eur Hear J. 200829.71-78

4.Andersen K. Risk of arrhythmias in 52,755 long-distance cross country skiers: A cohort study.
Eur Heart J 2013 Dec 34(47) 3624-3631