medical metamusings

Celiac Disease,Osteoporosis and Screening

2005-03-14T05:06:00.000-08:00

Stenson et al writing in the Feb. 28, 2005 Archives of Internal Medicine report the results from screening women for celiac disease (CD) in the Washington University bone health tertiary referral center. Finding a prevalence of 3.4 %, they recommend screening osteoporosis patients with two sensitive and specific blood tests (anti-TTG and anti-EMA). The women in the Wash.U.group underwent diagnostic endoscopy to confirm the diagnosis.The companion editorial suggests that if both tests are positive perhaps the endoscopy could be avoided.Cost considerations then become mandatory when screening for anything is at issue.
Dr.Bauchman in his editorial proceeds though the usual protocol of estimating the number of patients with a given condition who would need to be screened, the cost of screening all of them and the cost in this instance to prevent a fracture.We are told it would cost 2 billion dollars to screen the osteoporotic population.
The cost of the two blood tests are about $200.The 2 billion figure is what the Medical Czar of a country would consider. But then we have no medical czar and the relevant number is really the cost of screening for a given patient.The real life questions becomes will " insurance pay for it" and if not would the patient be willing to pay the money herself and will the physician be sued for missing a diagnosis if he does not test. Publications seem to always discuss these matters in global terms when maybe the locus of interest should be the individual doctor-patient interaction and relevant factors in that transaction.

Two insightful articles on Guidelines and why they should not be a major indication of "quality"

2005-03-01T12:19:00.000-08:00

An excellent article by Tinetti et al in the December 30, 2004 NEJM explains problems with guidelines particularly as disease specific guides are applied to patients with multiple illnesses. The second article is in The New Yorker by Atul Gawande and deals specifically with cystic fibrosis centers which apparently are a guideline dominated enterprise and how the very best such places go beyond guidelines. Guidelines are great for folks who purport to measure quality because they are easy to use. It recalls the old story that talks about the drunk who searched for his lost keys under the street light- not because he lost them there but because it was the easiest place to look. Some of the pitfalls Tinnetti writes about are:1) the guidelines are often based on RCTs(often with relatively small improvements in relative risks) that have cherry picked subjects who do not have other illnesses,and exclude older people and go for a relatively short times whereas in real life patients have many problems , get old and take pills for a long time.2) patients with several illnesses might just not have the same priorities as the trialists and may opt to not take all of the meds that Multiple guidelines offer,3) multiple drugs have multiple interactions.Extrapolating from RCTs that exclude many of the patients actually seen by doctors to recommendations about those patients seems to involve more faith based that evidence based medicine.Worse yet, physicians who have philosophical problems with those extrapolations may be judged to not be practicing quality medicine. The issue here is should RCTs' conclusions be construed narrowly- ie to those only like the participants in the study- or broadly -ie to include patients whose characteristics would have not allowed them to be eligible for the trial. Perhaps older more experienced physicians are more able to see when guidelines are appropriate and when they are not: when patient preferences and other variables trump the guideline's suggestions.
Quality assurance programs have as a given that variations are not desirable but there are appropriate variations due to the various specificities of the patients and the patient's own preferences. QA programs assume variations are bad. Gawande's article make the point that something more than adherence to guidelines makes a program great. It seems that it has something to do with having a great doctor involved: one who understands the basis for the guidelines and knows when to innovate and improvise. So much of medical care is improvisation by the physician and the patient. There is a sense in which QA program miss that point entirely.

TB Rx= quadruple therapy plus liver and onions

2005-02-26T10:23:00.000-08:00

Actually, you can hold the onions. The February 2005 issue of Chest published an article taking a very old observation(low cholesterol in tb patients) and decided to do something about it.What they did was a clinical trial involving giving cholesterol rich diet to see if a metric of improvement would occur quicker.Actually a couple of indicators did.By week 2, 8/10 in the treatment group achieved a negative culture while only 1/11 in the control group was negative.The authors also reported that sputum production decreased faster in the treatment group.Since 90% plus of tb patients are sputum negative by 6 mos anyway it is not likely that high fat diet diets for a couple of weeks will add much to the final outcome(and this is the era of outcome research)

WHI Strikes Again, A RCT trumps a systematic review and we learn estrogen does not help urinary incontinence

2005-02-23T05:07:00.000-08:00

Once again we see a RCT provide a conclusion opposite to that supplied by a systematic review even one done by the legendary Cochrane Group. A 2003 Cochrane review (Moehrer B ,Jextall A, Jackson S, Oestrogens for urinary incontinence in women. Cochrane Data Base Sys rev.2003:(2) CD001405) concluded that oral estrogen treatment could improve or cure incontinence but ,of course, in appropriately cautious tones, recommended further study.
The further study is found in the February 23, 2005 issue of JAMA. Data from the Women's Health Initiative (WHI) showed that estrogen alone and estrogen plus MPA increased the risk of urinary incontinence in continent women and worsened the incontinence in symptomatic women after one year. In a related editorial Dr. Catherine DuBeau attempts to unravel the knotty aspects of biological plausibility and the ins and outs of methodological issues involved in part to try and understand why oral estrogen would worsen incontinence and why progestin seemed to mitigate the effect of estrogen on urge incontinence in the WHI data. The relative risks, though statistically significant,were generally less than 2 and maybe the play of chance is at work in some of the subgroup data. But the bottom line is doctors will likely not be prescribing oral estrogen for urinary incontinence after reading the WHI paper. We await further investigation on the use of topical estrogen.

Prophylactic antibiotics in Surgical Patients

2005-02-22T05:21:00.000-08:00

A large survey published in the February 2005 Archives of Surgery reported that 99% of Medicare patients undergoing any of the five surgical procedures they reviewed received prophylactic antibiotics.1% developed wound infections. 92 % received antibiotics in compliance with published guidelines. Areas that the authors suggested could be problem areas were : possibly as many as 60 % received antibiotics for periods longer that some would say is optimal, possible overuse of vancomycin, and not all received the antibiotics within the usually recommended one hour of incision (Although, the exact time of incisions was frequently not recorded so this data is a bit soft) . The authors admited that their vancomycin-use analysis was limited by the fact they had no information about the frequency of MRSA in the various hospitals. These criticisms notwithstanding the apparent bottom line is there seems to be a very low incidence of sugical site infections. Duration of antibiotic therapy continues to be an area with more opinion that data. Critics of health care won't find much about which to express alarm but they will find something.

The Perfect Country and Western Song-The perfect Medical article

2005-02-19T09:58:00.000-08:00

In the David Allan Coe song, "You never even called me by my name" we are told some of the essential components of the " perfect" country song. Things that should be mentioned are: trains, trucks, mama,prison and getting drunk.
There are also essential components of the perfect medical article and should appear in the introduction and/or the discussion and summary sections. They include: mention of evidence based medicine (this is required even if the article has little if any evidence actually presented), mention of the disease at issue being "a public health problem"(saying it is common is not enough), a word about "quality" and perhaps most importantly stating that "we must be good stewards in this era of scarity of medical resources ". Unlike the essential elements of C&W music, which are timeless, the medical article sine qua nons are of recent vintage.
Non C&W fans may claim that tired cliches populate some country songs. It could be claimed that "floating abstractions" and politically correct comments are the fluffy fillers of the perfect medical articles.

Likelihood ratios and Evidence Based Medicine, what does the evidence show?

2005-02-18T21:17:00.000-08:00

Part of the teachings of EMB is the use of the likelihood ratio. It is defined as the likelihood that a given test result would be expected in a patient with the disease of interest compared to the likelihood that the same result would be expected in someone without that disease. To use one , you have to "estimate" the pretest probability of a disease in a given setting. It has always appeared to me that this means- much of the time- you simply make up a number.If that is true, a group of doctors given the same clinical scenario would make up different numbers. Now there is evidence that this is exactly what happens. Drs. Phelps and Levitt (Acad. Emerg. Med,2004 June:11 (6) 691-694) gave clinical vignettes to a group of IM and ER trainees and attendings and asked them to estimate the likelihood of several illnesses. The numbers varied widely.The smallest difference in the pretest probability was 70%. If you think about "making up" a number as opposed to "estimating" a number, the validity of the whole process is perceived differently. Here, at least, the "evidence" that a particular element of Evidence Based Medicine is valid in a simulated real world setting is lacking and in fact suggests that it is not. The Ontario EMB experts in their book "Evidence Based Medicine" indicate there are several ways to estimate the pretest probability besides the physician using her experience including national and regional data bases. But in the real world it seems that the most common way of estimating pretest probability is to use one's own experience because such data is either non existent or you cannot access it. In this regard perhaps older, more experienced doctors would have the edge.

EMB dogma states that the likelihood ratio is the best way to judge how much a test result help to make the diagnosis. In theory this is clearly the case but the scheme does not work very well if the pretest probability value is is so nebulous.

Do older physicians not use guidelines? Are Internal Medicine Residents not taught ventilator use?

2005-02-16T13:00:00.000-08:00

In the Feb.15, 2005 issue of the Annals of Internal Medicine, one article paints a worrisome picture of older physicians while another article is quoted in a pulmonary disease review showing that internal medicine trainees do not seem to know much about ventilator use.

The paper (The Relationship between Clinical Experience and Quality of Health Care,Choudhry et al) casting a bad light on older doctors does not appear to represent the highest level of evidence. It is a review article of many articles whose methods and metrics differ widely and at least two of which are too old to have much current relevance.(These are two articles from the 1970s that show older doctors prescibed more chloromycetin than younger doctors). Many of the articles used questionnaires with variable response rates. While some of the articles reviewed used a "general knowledge assessment", many of the negative-to-older-doctors papers claimed older docs adhered to guidelines less frequently than younger one . Should quality be equated with adhering to guidelines? The accompanying editorial, rather than offering a scholarly critique of the methods, accepts all at face value and states "The profession cannot ignore this striking finding and its implications" More commonly an editorial would state the obvious need for more data and analyze the data critically rather than adopting a "its time to do something about it" attitude. I believe the editorial is overreaching-the article itself is more cautious in its conclusions- and since two of the authors are members of the American Board of Internal Medicine should it be considered self serving as the ABIM would have justification for more action items (testing re-certification etc) if in fact a problem exists with older internists. The editorial states "The message is clear for certifying boards." The "Summaries for Patients" section takes a much more cautious view saying in part " these findings do not apply to all older doctors and must be confirmed by more specific research" .
More solid was the data quoted in the "Update in Pulmonary Diseases" section. 259 residents in internal medicine took a 19 item question examinations. Almost half did not know how to set the tidal volume in ARDS. And only 46% of program directors thought residents had adequate knowledge of ventilators. If the ABIM is worried about what it should do about older doctors, they should be at least as concerned about current trainee's apparent knowledge gaps over which they exert more control .

Coarse Grain,Fine Grain distinctions in Medicine.

2005-02-15T13:19:00.000-08:00

Jacob Bronowski in his "The Origins of Knowledge and Imagination" speaks of a basic problem in the brain's mechanism in terms of achieving fine discrimination with a coarse apparatus.Further, he says that in many ways "about all" human problems..in science or in literature..center around the same problem.How do you refine the detail with an apparatus which remains at bottom coarse and grainy?"
Consider the randomized clinical trial(RCT) currently thought to be at the apex of the mechanisms we have to find the medical truth.We are left with aggregate data, groups numbers that are relevant , strictly speaking, to patients having the characteristics of those in the trial but is freqently extrapolated to include many other patients.
Compare this grainy-ness with the progress made in the following example.
Consider the use of MRI in a patient with the clinical picture of optic neuritis.
The finding of white matter abnormalities of a cetain type provide valuable information regarding likelihood of progression to multiple sclerosis. The coarse grain category of optic neuritis has been fine grained a bit by sorting out those patients with a high risk of subsequent development of multiple sclerosis.
But fine tuning cannot occur with the RCT. We can break the aggregate data into sub groups but we loose power to see differences and at the same time we increase the likelihood of Type I errors by cranking out many comparisons. So basically the RCT is a coarse grain apparatus and cannot get any finer, remaining coarse and grainy.
To fine tune the aggregate data seems to take determining the relevant pathophysiology.The example of TPMT deficiency comes to mind. Before the details of this deficiency were mapped out, we could only say that a certain percentage of children treated with a thiopurine type drug developed serious bone marrow failure. Once we learned what the pathophysiology was , testing could be done to see who comprised that percentage and the coarse grain became fine.

Cosmic Justice as a medical ethical imperative

2005-02-08T11:03:00.000-08:00

Thomas Sowell speaks of "Cosmic Justice". Is the" justice" appended to the ethical precepts of medicine this type of justice.Sowell in his book " The Quest for Cosmic Justice" argues that the traditional American justice is basically applying the same rules and standards to everyone. This is in contrast to "Social Justice" which involves redressing those inequalities that proponents characterize as the fault of society.Sowell argues further that social justice proponents seek not to just correct the sins of man (or society) but "the oversights of God or the accidents of history" as they bring about inequalities.So social justice is really cosmic justice.

The "big four" medical moral principles are respect for autonomy,beneficence,non-malficence and justice. ( Beauchamp, T;& Childress, J. (2001) Principles of Biomedical Ethics. 5 th ed. Oxford Univeristy Press, Oxford) Justice is the most recent on the ethics scene and the one , I believe, most difficult for physicians to wrap their minds around. Some would argue for a big three leaving out justice as it may conflict with the beneficence clause. But the establishment's party line includes it and is increasing being emphasized. And the justice that is proposed is "social justice". (Medical Professionalism in the New Millenium. A Physician charter. Annl Int Med 5 Feb 2002. VOl 136, pg 243-246)
Executing the first three may be difficult in a individual case but conceptually seem easier.Do no harm, respect the autonomy of the patient and act to benefit the patient. These resonate with what happens most of the time in a doctor patient encounter. But Justice is less clear. In the world of social justice it has to do with "allocation of [scarce] medical resources"How does one make that operational? It can only be made operational through population based assessments and recommendations .The individual practioner and his patient -concerned as they are-with their localized points of view cannot see the big picture and have to be told what to do by the guideline writers and the cost benefits analysis experts. To value the good of the group-as impossible as that is to delineate-above the good of the individual patient is not to start on a slippery slope , it is to go off the cliff.

The last gulp of "Sodi water" ? Once again a large RCT trumps a meta-analysis

2005-02-03T06:48:00.000-08:00

As early as the mid 1960's an infusion of glucose, insulin and potassium was being used to treat myocardial infarctions having been introduced by Dr Demetri Sodi-Pollares.Over the years a number of small clinical trials seem to indicate the value of this "polarizing solution" that-at least when I was a house office- was known as sodi water.Also a meta-analysis indicated its efficacy. Now a very large (n=20,201)RCT has shown it to be of no value some 40 years after its introduction.
The CREATE-ECLA RCT was conducted in 470 centers through out the world and showed no difference in mortality,cardiac arrest or shock in patients with STEMI treated with the GIK solution.
Once again a large RCT provided results contrary to an earlier meta-analysis.Why does this happen? The usual suspects are: publication bias and poor methodology in some of the trials included in the meta-analysis.Adding up a number of questionable trials does not equal one large well done trial.

Two underwhelming articles from this week and Kudos to the Cleveland Clinic

2005-02-02T07:18:00.000-08:00

Carratala et al from Barcelona writing in The Feb. 1, 2005 issue of the Annals of Internal Medicine offer rather weak data suporting the predictive value of the PSI (Pneumonia Severity Index). Patients in PSI categories II and III were randomized to outpatient treatment with oral levofloxacin or in patient treatment with I.V. levofloxacin. The results were about the same in terms of complications, etc but the outpatients were more satisfied with their care. It seemed fairly obvious prior to this article that if patients are not too sick with community acquired pneumonia outpatient oral antibiotic therapy is adequate and patients would generally rather not go to the hospital.
Even more obvious and expected were the results of an article by Smith et al in the February 2, 2005 issue of JAMA.A survey was done on 32 private clinics in Colorado. Questionanaires were completed and the data showed that in 13.6 % of visits there was missing clinical information, eg lab reports, xray reports etc.Further the data showed that some finite amount of time was spent in searching for the records and that in the opinion of the responding physicians this might result in patient delays or additional services.So it seems that sometimes items are missing from charts and time will be spent trying to find them. Could not any physician who has ever worked any where have predicted these findings ?
To end on a more positive note,Cleveland Clinic's EMR performed impressively in notifying patients about the Vioxx issue. In less than 24 hours 11,699 letters were sent to patients regarding the rofecoxib recall. Details of their activites are found in an article by Jain et al in the Feb. 1, 2005 Annals of Internal Medicine.

Internists as "the doctors for adults"

2005-02-01T10:43:00.000-08:00

The American College of Physicians published results of surveys that indicated that around half of those iterviewed said they did not know what an internist was and some of the other half had it wrong.The College has had a "Doctors for Adults" slogan for a number of years and uses it in its advertising,an effort whose aim, at least in part is to correct this ignorance.
One wonders how this slogan differentiates internists from family physicians who also see adults with the same range of medical problems as an internists.Actually,the typical family practice doctor sees and treats more adult problems because of their training in and presumably comfort in managing office orthopedic and office gynecology problems.
At least some in the American College of Physicians want internists to be more like family practioners if the content of some of the recent ACP meetings is any indication.The offerings have including reviews of office gynecology, and woman's health issues and even a mini course in how to do skin biopsies. If an internist is concerned with a nevus on his arm,how likely is it he will say "I think I need to go to an internist to get a biopsy"? Will an internist with irregular periods likely consult with an another internist rather than a gynecologist?
Surveys show the average incomes from family practice doctors and general internists are about the same. So the third payer distorted "market place" does not seem to value internists services more than FPs and surveys indicate many patients do not know the differences anway- if there are any.
As there is more and more pressure to treat hypertension, diabetes etc with guidelines,what extra can the internists offer as any physician presumably can read and carry out the guides? As an internist,I want to believe there are "extras".
The medical landscape has changed so much since I received my internist credentials over thirty years ago that it is hard to rationalize a career choice in general inernal medicine today.There is mananged care pressure from one side and competition from family practice-not to mention nurse practioners and physicians assistants- from the other side.The American College of Physicians offers only a lame slogan,courses in how to be more like a family practice doctor,and exhorts its members to somehow help achieve "social justice" i.e. a "fair" distribution of "scarce" health care resources.

Statistical Independence is not necessary or sufficient for causality (and is evidence based medicine really faith based at the bottom?)

2005-01-27T08:00:00.000-08:00

Daniel Brotman's article in the Jan 24, 2005 issue of the Archives of Internal Medicine(vol. 165 p138-145) makes important points regarding the concept of "independent risk factors". Basically,he and his coauthors remind the readers that: statistical independence does not mean causality, is context dependent ( ie in that particular data set) and risk factors may be causal even if not statistically independent. Independence is a statistical concept relying on a particular statistical model.

I remember discussing the role of elevated triglyceride values in the context of heart attack risk and downplaying its significance because I had read triglycerides were not an independent risk factor. Now, or course, clinical studies have shown the opposite. The point is that a risk factor can be "significant" i.e. important whether or not a medical publication's analysis indicates that is an "independent risk factor"

Articles like this one are important antidotes to the faith that we tend to have in the black box magical output of multivariate analysis. Few physicians have plowed through the pen and paper process of doing a multivariate analysis or even understand generally what it all about.I don't claim to. That exercise might give one a real sense of what is being done and perhaps how small variations in data input can alter the answer- changing an independent risk into one that is not and vice versa.

In regard to heart disease, the authors assert that as more variables are linked to disease, no study will be able to properly model all the risk factors to enable them to say that X is an independent risk factor. This problem of residual confounding limits medicine's search for the causes and might make us more circumspect when we make pronouncements to patients about what causes what and what we should do about it.

William Barrett In his book "Illusion of Technique"(Anchor Books, 1979) says that Logic is the only modern science that has shown its own limits by showing the limits of formal systems(through the work of Godel and others). We might tend to forget when we read " X is an independent risk factor for disease Y" that we are dealing with "provisional conclusions " extracted from "fragmentary" data. Some have make a distinction between "faith based" medicine with "evidence based medicine". Considering the faith required to believe the output of mysterious mathematical models about which most physicians readers are ignorant, this distinction begins to fade away.Maybe we need a medical version of Godel's theorem as an antidote to hubris or faith based believe in technique. I eagerly await more articles,such as Brotman's,pointing out the limits of medicine's knowledge-gathering techniques.

The New Medical Paternalism

2005-01-23T11:57:00.000-08:00

The paternalism that was- to varying degrees- part of medical practice has largely been removed by the priority of patient autonomy and the need for informed consent. Medical ethicists seemed to agree that autonomy was important leaving little or no place for paternalism. But the paternalism as we knew it (the physician deciding what was good for the individual patient and not necessarily involving the patient in the decision) is being reborn in a much more dangerous type paternalism.

I referred to this as the "New Paternalism" in a letter to the editor of the JAMA rebutting the position of Dr. David Eddy who advocates a medical practice based on the good of the group and not of the individual patient. (JAMA April 5, 1995, vol 272, no 13 pg.996) .

The abrogation of the individual patients' welfare to the collective good is implicit in the [new] medical professionalism as articulated by the Charter of Medical Professionalism which was published in both the Lancet and The Annals of Internal Medicine. A cogent critique of this "Charter"by Dr. Jerome C. Arnett, Jr. can be found in the Medical Sentinel 2002;7 (2) 56-57. and I will not attempt to improve on his comments. Internists who have read the Annals publication of the Charter should read Arnett's paper to see what their professional organization is advocating.

What I find particularly frightening is the unabashed, explicit suggestions for implementation of this approach in the series of articles by Eddy in reply to which I wrote the 1995 letter.
Eddy (Eddy DM.Rationing resources while improving quality.JAMA 1994;272;817 824) said we must "help patient understand the consequences of a limited resource pool and the need to be fair" and he continued " in most cases the explanation might be "Well, for patients like you the appropriate approach is ...".
Dr. Robert L. Wears in his letter to JAMA said " patients in general (society) must agree to this return to a beneficent paternalism"as at least he seemed to believe that before someone would be sacrificed to the collective good, he should agree to do it. Of course "society" being a figure of speech cannot agree to anything, only individual patients could agree or disagree.
As arguably bad as the old paternalism may have been At least an individual doctor decided what was best for the individual patient.With the new paternalism the medical elite versed in the ways of outcome analysis and cost benefit analysis will decide what is good for all the patients while the individual doctor and the individual patient's assessment and values are no longer relevant let alone determinative.
Similar views to those expressed here were published- in the same general time frame as the letters to JAMA- by Chervenk and McCullough in an article in J.Clin.Ethics 1995;6:320323 titled "The threat of the new managed practice of medicine to patients'autonomy."

A Randomized Clinical Trial may tell us what to do... or not

2005-01-22T08:47:00.000-08:00

Since it is believed that testosterone is involved in prostate cancer it seemed reasonable-biologically plausible-that a drug that inhibits the conversion of testosterone to dihydrotestosterone could decrease prostate cancer risk. So the Prostate Cancer Prevention Trial was instituted.18,000 men studied for seven years with the treatment group taking finasteride. Happily, there did seem to be a decrease in prostate cancer (a 24.8%decrease in prevalence in the seven year period of the trial) in the group given 5 mg. finasteride daily. However, there was an increased risk of high grade cancers in the finasteride group.37% of the tumors in the treatment group were Gleason grade 7 or higher versus 22% in the placebo group. The increase in high grade tumors was, of course,an unexpected finding.A decreased prostate cancer risk was expected-or hoped for- and occured. But now what advice would you give someone in regard to taking finasteride? Previously we could say finasteride could decrease prostate size and might decrease cancer risk.But now ...
"We have a drug that will decrease your risk of prostate cancer a bit but if you do get prostate cancer it may be a more malignant kind". Not a great offer.
For those who think RCTs give us clinical truth (and sometimes they probably do) the PCPT is a good example of how RCTs can make the clinical waters even more opaque.
Urologic science is undaunted. A new trial is planned (or possibly now underway). The REDUCE trial (J Urol.2004 oct:172 (4 pt 1) 1314-7) will enroll 8,000 men to take either placebo or a different 5 alpha reductase inhibitor,dutasteride for a projected 4 years.After the PCPT results what would you be able to say to eligible trial participants that would induce them to sign up? Well you do get free prostate biopsies and maybe this time there will be no surprises.

Decisions, "Society" and Thomas Sowell's Insights

2005-01-18T05:31:00.000-08:00

Relatively few books provide insights so powerful and useful that they can change your way of looking at things. Thomas Sowell's book, "Knowledge and Decisions" ( Basic books, 1996) is such a book.

Consider the first sentence in Chapter 2 "despite the fashionable practice of personifying "society" as a decider and actor, decision making in the real world can be understood only in the context of the actual decision making units (DMUs- my abbreviation) that exist, and the specific, respective sets of constraints and incentives within which each operate".
He emphasized that the term society is a metaphor."There is no one called"society" that decides anything." He continues to say that sometimes this metaphor is used to shift the decision making from smaller and more numerous units to a single national wide unit. No DMU controls a whole society except to varying degrees in a totalitarian state.
Some may consider the government as the institutional personification of "society". Of this Sowell says "...the diversities,conflicts and disparate incentives and constraints which make "society" a meaningless abstraction as a decision making unit also make government a fragmentary aggregation of decision makers."

Discussion about various issues, e.g. "distribution" of health care, overlooks-through ignorance or intention- the fact that the most basic decision is who makes decisions and under what constraints and feedback.

Medical Journal articles abound with comments such as "society can or cannot afford this or that" . The things to remember there are: 1) society is not a decision making unit 2) issues that are addressed by the "society" obfuscation need to be thought of in terms of the incentives and constraints of the various DMUs potentially involved and 3) Government is not society (articles frequently propose or at least imply a governmental solution to the issue at hand).

The "Moral Interconnectedness" of Medical Care

2005-01-14T14:01:00.000-08:00

Brennan (Brennan TA.An ethical perspective on health care insurance reform.Am J Law Med 1993:19:37-74 ) has asserted that a physician's decision about one patient affects all other patients.On first analysis this statement sees incomprehensible.. How, for example, does my prescribing a low dose diuretic to a person with hypertension -in any real existential way-affect a person three thousand miles away with a sore throat.Presumably we are not talking about some type of strange quantum physics effect where we are told somehow there is action at a distance.Why would we not assert -making just about as much sense-that a car repair decision in Atlanta affects all car owners?
He speaks of the moral interconnectedness of medical care. This cannot be taken literally so it must be intended in a metaphorical way. If metaphorical is it of the same genus as "it takes a village to raise a child" and "we are all in this together" and "global village" comments.? What is the purpose of evoking such a metaphor?

If one accepts these notions as something more than an absurd figure of speech,then the following proposal is not surprising. This is the proposal of "social justice" as a fundamental principle for the [new] medical professionalism as revealed in the Feb 5, 2002 annals of internal medicine, vol. 136, number 3, p 243-246.

Hayek's critique of the concept of "social justice" is worth serious consideration as physicians are now being told that it is a fundamental element of their professionalism.
The following are some of his analysis of this concept as described by Michael Novak. (Firstthings.com)
The term is vague and typically undefined."It is allowed to float...as if everyone will recognize an instance of it when it appears."
It can become an instrument of ideological intimidation for the purpose of bringing about some change desired by the speaker.

"Social justice" in the medical professionalism charter is "defined" as calling upon the profession to promote a fair distribution of health care resources. What remains undefined is "fair distribution" and the means to enforce this distribution and over what group of people should this distribution occur.

Only one published letter to the editor challenged the basic premises of the charter's authors.
When one reads the letter and the author's reply it is clear no reconciliation of views is possible.
Dr. Jerome C. Arnett Jr. wrote that individual rights and group rights are mutually exclusive;the authors reply "we strongly disagree". Arnett wrote than-other than under socialized medicine-the provision of services to one patient does not diminish that available to other.The authors reply "We also disagree". However, to his comment " How...is it ethical for a group such as the Medical Professionalism Project to weaken our code of ethics to promote a political agenda...?"The authors said only the charter is not a code of ethics. Apparently they choose to not deny that they had a political agenda.
When one talks about social justice, doesn't one always have an agenda ? And is not talk about "moral interconnectiveness" etc an attempt to build a base for such an agenda , however vacuous such a base may be?

The Internet, the wrong kind of vertigo and Hickam's Dictum

2005-01-12T13:10:00.000-08:00

A vignette in which Hickam's Dictum trumps Occam's Razor as a patient labeled as having Meniere's Disease discovers-thanks to Google- she really had a different kind of vertigo.
A 43 year old lady developed aural fullness, tinnitus and unilateral hearing loss and is told she had 2 of the 3 criteria for the diagnosis of Meniere's Disease. Within a few weeks she developed vertigo ( now she had the third symptom) which was precipitated by head movement and lasted only a few minutes. Researching her condition on the web she learned that the typical vertigo of Meniere is episodic and may last from hours to days and the type of vertigo she experienced seemed more like that described as BPPV. She told an audiologist of the symptoms and was treated with the Eply manuever. She had been free of vertigo since that time.
Even though she had the classic triad of Meniere's she may have actually had Meniere's without vertigo-people write of such an entity- plus BPPV.
Had she not researched her condition no one might have tried the otolith repositioning manuever.
Hickam ( if there really was such a person) purportedly said " A patient can have as many diagnoses as he darn well wants", Occam's Razor notwithstanding. ( Hickam's contribution to medical diagnostic lore is a bit obscure-I only got two relevant hits on a Google search on 1/12/05)

Can "Society" Afford so many Cell phones?

2005-01-05T14:26:00.000-08:00

Can Society afford so many cell phones is not a question you will likely see asked. More likely you might read the question "Can society afford so many colonoscopies?", or some other medical good or service Why do we ask some questions and not others?. Concern about cost and cost benefits analysis (CBA) are common now in medical publications.

CBAs are typically cast in terms of the cost to "society". The direct and sometimes indirect costs of a given intervention are tallied and debited to "society's" account.
Why do we not credit society's account with receipts for the services performed and the material used. One man's costs is another's revenue. Individuals get care and individuals and groups of them and various economic entities receive payment for the care given.
"Society" is not some third payer in the game. Society is not some super entity. Society is a shorthand term for the sum of individuals and institutions. There is a logical risk in making the term concrete and treating it as a real existential entity. Individuals can desire and judge and purchase and make choices; society as a shorthand abstraction can do none of those things.
Why are costs decried in this particular area of economic activity? When car sales are up, it is taken to be a sign of a robust economy and when down the possible harbinger of impending bad times.
Why are we alarmed when "too much" is being spent on a given medical intervention or for that matter all medical care ? Why is buying iPods good and buying flu shots not?
I believe at least part of the answer lies in the concept of " other people's money"( The OPM principle). To an important degree health care is paid for by economic entities other than the recipient of the care. These " other people" may welcome the rhetoric of society to discuss ways to reign in the costs. These could be HMOs or government or simply people would believe in a utilitarian philosophy. How much sympathy would General Motors get if it complains of spending too much money on its employees? Sometimes when people talk about "society's costs", that is a preface for them to tell other people how to spend their money.

Evidence Based Medicine-The Dark Side Part two

2004-12-31T04:45:00.000-08:00

The core of EBM is the randomized Controlled Trial (RCT) and the systematic review ( meta-analysis) of multiple RCTs.

Two recent and widely quoted meta-analyses (MAs) of mammography effectiveness reached different conclusions working with the same original data base but eliminating different studies from the universe of analysis. Olsen and Gotzche from Denmark (Screening for breast cancer with mammography.Cochrane database Syst.Rev.2001;CD001877) eliminated all but two studies in their MA and found that the all cause mortality was no different in the screened group. The USPSTF analysis was more inclusive in their pooled analysis and found a 16% reduction in breast cancer mortality. What do you do when the meta-analyses conflict?

Steve Goodman (Ann Int Med 3 sept 2002 volume 137 issue 5 pages 363-365) explains that a MA itself is basically an observational design using published studies as the subjects. What subjects you keep and which you eliminate from the analysis obviously can turn the results of the analysis around. He says " This controversy shows that the justification of why studies are included or excluded ...can rest on competing claims of methodologic authority" These claims, he says, " look little different from the traditional claims of medical authority that proponents of evidence-based medicine have criticized"
In the RCT the process of subject elimination is more transparent and once the study is underway there are safeguards against eliminating subject whose upcomes go against the researchers desired outcome.MAs are transparent to the extent that the reader is informed of what studies are eliminated but there is nothing to prevent the researcher from doing pre study simulations to see what eliminations lead to which results and proceeding accordingly. Out right fraud could occur but more likely the bias of the researchers would be the culprit. The point is the MA could be rigged.Entities (HMOS, Governments etc) who incur costs with a given medical intervention would welcome MAs that show no effectiveness. Follow the money.

I think the main point here is really a MA should be considered context dependent not universally true. The context is which studies are included and ignored and what is the outcome statistic used. In the two studies quoted above, different data sets were selected and difference outcome measures used. So " Is mammography effective"?, well,it depends.

Evidence Based Medicine- The Dark Side Part One

2004-12-30T13:24:00.000-08:00

The most recent definition of Evidence based medicine (EBM) preempts criticism in its inclusiveness. " The integration of the best evidence with clinical expertise and patient values" Previous criticism of EBM claimed there was neglect of clinical expertise and the patient's values and desires.
Who could object to the inclusive definition." It is mom and apple pie and more pie. Surely there could be no dark side to that.

However, when most physicians think of EBM,their thoughts focus on randomized control trials (RCT) and meta-analysis rather than the all embracing arguably vacuous definition. This is because RCTs and meta-analysis are really what EBM is all about.
A darker side could emerge if in the zeal to champion the RCTs the other factors one needs to consider are neglected. Those factors are, of course, prior evidence and biological plausibility.Dr. Steven Goodman from Johns Hopkins has cogently argued for this as have Sehon and Stanley in a wide ranging and very interesting philosophical analysis of the EMB issue.
Another author, Miles Little,(ANZ Journal of Surgery.Vol.73,issue 4, pg 177, April 2003) speaks of EBM's "cult status" and lists 8 areas of concern including its unwitting paternalism,its unstable truths and its reductionism.
Bandolier ( a journal of evidence based medicine) admits that references to EMB can serve as a talisman. To say that the author's position is evidence based is supposed to end the discussion much as saying "its God's Will" might have served in an earlier era.

In anyone thinks there will always be an arrow from RCT to clinical algorithm for all or most clinical problems here are few of reasons why that will not be true. There is not enough time or money or interested funding groups to do all the RCTs needed for all the issues. RCTs may be contradictory (i.e. ALLHAT and the 2Nd Austalian National blood pressure study). RCTs become outdated as technical advances pile up faster that RCT can catch up.

If there are problems and limitations with RCTs, there are meta problems and issues with meta-analysis, an issue to consider later.

McMaster Clinical epidemiology Group: Evidence based medicine is best spoon fed

2004-12-30T13:22:00.000-08:00

In an April 2000 BMJ editorial(BMJ 2000:320. 954-955 (8 April)) Jaeschke,Cook and Haynes-from the McMaster Clinical epidemiology Group- state that their residents as well as British GPs prefer "preappraised " evidence, rather than doing the analysis themselves. They have concluded that not all trainees are interested in attaining advance EBM analytic skills. The interesting thing here is how the authors reached that conclusion. It was not through a randomized controlled trial, nor was it through a systematic observational study but as they admit "after a decade of unsystematic observation".This is the type of clinical evidence that they -rightly enough-have placed on the bottom tier of the clinical evidence hierarchy. Is this not the same type of evidence that they denigrate in their advocacy of the RCTs. How does their pronoucement differ from the dogma that old clinical profs passed down to their proteges? And yet it is on that basis that they make their recommendation of best ensuring evidence based care by supplying preappraised evidence based summaries. Does this sound like "Don't worry we will analyze the data and tell you what to do"? Is there a difference between the dogma we learned from old clinicians based on their experience and the dogma from the EBM analytic experts? In either case it seems the trainees of days gone by and the trainees of today want to be told what to do. What do the trainees do when two meta analyses on the same issue differ?

The random and the deterministic in medicine

2004-12-28T13:44:00.000-08:00

Forty years ago pathophysiological concerns were stressed in medical education and statistics and epidemiology were little more than John Snow and the Broad St. Pump and the mean and standard deviations and t tests.The landscape has changed. Logistic regressions, Markow simulations, and even more obscure statistical tools populate the methods sections of medical articles.There is much "black box" output.
There is a theme in the history of medicine of an affection for determinisitic thinking and an antipathy for statistics. Statistics, after all, to a large degree began in the study of gambling. Coin flips, and rolls of dice were not the stuff that physicians were concerned with. When did the pendulum swing so far to the data side ? When did concerns with aggregate data begin to push out thoughts about what exactly is going on?.
The following is an example how how what at first seemed to be a random occurence was determined to a large degree by a SNP or single nucleotide polymorphism. The small percent of children treated with thioprine type drugs who developed a serious leukopenia did appear random until it was learned than about 1/300 Caucasians are deficient in TPMT (Thiopurine methyl transferase) which in turn was caused by a single misplaced nucelotide. Now testing for that enzyme deficiency or for the genetic variation allows for downward adjustment of the chemotherapy dose for those patients with TPMT deficiency and the previously random serious marrow damage is avoided.
Of course, every situation with bad clinical outcomes that can be described in aggregate numbers is not that simple. But, at least some of the time what appears at first to be random is shown to be determined by a describable -and often controlable -mechanism. At least some of the time and and at some level random is simply ignorance.
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subject matter experts and methodologists

2004-12-26T13:17:00.000-08:00

The American College of Chest Physician's most recent treatise on venous thrombosis (The seventh ACCP Conference on Antithrombotic and Thrombolytic therapy)mentions in its methods section that two kinds of experts are involved in their very labor intensive review.There are subject matter experts -these presumably include physicians who actually treat DVTs- and also individuals who are well versed in statistics and the methodology of various aspects of clinical epidemiology. I believe this is a good thing. Less of a good thing are a number of articles I have seen over the past few years where all of the authors seem to be or at least tacitly claim to be in the latter category. Typical is a review article (a "systematic review") by generalists of a topic traditionally in the purview of a specialist, for example Parkinson Disease. As likely as not the multiple authors are members of a general internal medicine department and several if not all have appended to the defining initials after their names the letters"MPH". Their methodological reviews may be good or not but what is often missing is the insight of a subject matter expert.For example, someone who has actually treated many patients with the disease of interest. Such a person can put the data analysis in some type of real life clinical perspective.
Thirty years ago journal editorialists needed only to be the subject expert.Now they also either need to be experts in or need the help of experts in statistics and epidemiology to put issues into a contextual mix blending an analysis of the data currently being published with the prior evidence,the biological plausibility concerns and the clinical relevance.
I believe that review articles should routinely include among the authors someone who is in fact a subject matter expert even if others do the methodological heavy lifting. There is plenty of room for both types of experts in the advancing of medical knowledge and both types are needed.Evidence based medicine is currently defined as the integration of the best evidence with clinical expertise and patient values. Liklihood ratios and "NNTs" are great-atleast some find them useful- but we also may benefit from the insight from someone who knows the trees as well as those who describe the forrest in aggregate data terms.

There is a fundamental conflict regarding how to determine the effectiveness of cancer screening

2004-12-26T09:50:00.000-08:00

Current preventive medicine (apart from immunizations) focuses on cancer screening and coronary artery disease prevention. Cervical cancer screening has moved past the stage of debate. Screening for breast cancer, colon cancer, prostate cancer and lung cancer have not, although different aspects of each are at issue.

In the debate about the value of lung cancer screening a foundational conflict about how decisions are made regarding the effectiveness of screening becomes evident. Specifically, the question becomes which statistical method should be determinative in analyzing the data from randomized population screening trials. Those who believe the final answer lies in disease specific mortality have decided that lung cancer screening is of no value (and this view is the more commonly held one). Dissenters believe that in this type of trial-as opposed to a treatment trial-cure rate or five year survival is the analytic technique that uncovers the truth. A prolific advocate of this dissenting view is Dr. Gary M. Strauss. According to the generally accepted paradigm a reduction in the cause specific mortality in a randomized trial is accepted as the definitive measure of effectiveness. Strauss and others question the assumptions underlying the paradigm.
It gets more complicated. Dr. William C. Black in the Feb. 6, 2002 issue of the Journal of the NCI argues that all cause mortality may be less affected by bias than disease specific mortality. Once the data are collected, and in these screening trials it may take years, the problem remains that there are widely different views as to how to analyze the outcome (i.e what measure of effectiveness do you use) and the method you choose may determine the answer and therefore policy decisions and advice to patients based on the study.
Most of the controversy over lung cancer screening involved trials using chest xrays. As thoracic imaging evolves, similar rhetorical exchanges will likely take place following publications of screening projects with various generations of CT scans.

Does this mean that our ability to use the tools of epistemology lags behind our technological advances?

Relative risks less than two

2004-12-25T08:40:00.000-08:00

A recent article in Annals of Internal Medicine claimed that Vit E increased the risk of death. The relative risk (RR) was 1.01. If a relative risk of 2 increases the risk of the outcome of interest two fold,then a relative risk of 1.01 increases the risk by 1/100. This is clearly a difference too small to really measure and too small to care about.
Relative risks of less than two are frequently published in medical journals and often represent more noise than signal but when repeated in the lay press alarms some,confuses others and generally give even more reason for folks to think that the medical profession is not too sure about much of anything.Of course, a relative risk even as "big" as two does not guarantee a causal relationship, but courts are beginning to accept a relative risk of 2 or more as fulfilling the "more likely than not" standard of proof for some types of civil litigation. Let's not forget the role of prior evidence and biological plausibility in considering what significance should be given to " statistically significant" RRs.