How Reliable is a Drug Research Report?: Absolute vs. Relative Risk

A drug company reports that taking their new drug Dammitol results in half the number of heart attacks compared to those not taking the drug. Fifty percentage less sounds pretty good. However, if a population of 100 is what is being studied and normally there are only 2 heart attacks in that population, a 50% decrease in heart attacks is not as impressive. It means that the number of heart attacks has only decreased by one out of the 100 people studied, or 1%. A 50% decrease in heart attacks is the relative decrease. A 1% decrease in heart attacks is the absolute decrease. The drug company reported the relative, rather than the absolute, decrease in heart attacks, thereby making the results look better.

The same company also reports that there is only a 1% increase in the side effect of splitting headache from Dammitol compared with a placebo. However, if two people get the side effect on the drug, and only one gets it on placebo, this means a relative 100% rise in side effects on taking the drug. The drug company would not report a 100% increase in splitting headache, but phrase the results differently, namely that the drug causes only a 1% increase in the headache, from 1% off the drug to 2% on the drug, the absolute increase.

The problem is that drug companies sometimes report only relative results when it comes to making the drug look effective, but absolute results when referring to the side effects. It is important to distinguish whether the results are relative or absolute. When unclear, it is best to look at the raw data of number of patients rather than just the percentages.

For further information see Clinical Biostatistics and Epidemiology Made Ridiculously Simple, by A. Weaver and S. Goldberg, Medmaster.

Complementary and Alternative Medicine (CAM), Medical School Curriculum, medicine,allergy, immunology,asthma

Correlation Does Not Mean Causation


1. Shoe size is directly correlated with neat handwriting. Does this mean that there is something about increased shoe size that causes neater writing? Or is it because older children wear larger shoe sizes and by virtue of age, are more mature and write more neatly than toddlers? The correlation does not mean causation.

2. The number of drownings is highly correlated with the time of year, namely summertime. This does not mean that summertime causes drownings. There are more drownings because more people swim in the summer.

3. Myocardial infarctions are correlated with elevated troponin levels. This does not mean that troponin levels cause myocardial infarctions. It would be a mistake to try to treat heart attacks by lowering troponin levels, when in fact it is the MI that causes the elevated troponins, which leak out of damaged myocardial cells. Too obvious? How about the following:

4. Elevated blood homocysteine is correlated with increased risk for myocardial infarction. Does elevated homocysteine cause heart attacks? Studies designed to decrease homocysteine have not demonstrated any lessening of the risk for MIs. Perhaps a third factor causes a rise in homocysteine as well as a susceptibility to MIs.

5. Elevated LDL cholesterol is correlated with increased risk of cardiovascular disease. If a third factor (e.g. stress, heredity) is the cause of both cardiovascular disease and elevated LDL, it may not help to try to control arteriosclerosis by taking years of anticholesterol medication. Current medical opinion leans heavily toward LDL cholesterol as a causative act in cardiovascular disease, but there are those who disagree.

6.  Hypertension is believed to cause arteriosclerosis. But could a third factor (e.g. stress) be implicated as a cause of both?

6. According to a 2005 study in Finland, women who have abortions are more likely to commit suicide. Do abortions cause suicide, or are women who have abortions more likely to be in social situations that in themselves are more likely to promote suicide? Women who have abortions also are more likely to be murdered and die in accidents. If they are already high-risk for murder, suicide, and accidents, they may be more likely to be in situations where they choose an abortion.

7. People often are quick to judge patterns and often attribute causal importance to patterns that are only coincidental. I had an elderly patient who was sure he knew what caused Parkinson’s disease; he had purchased his home from someone who had Parkinson’s disease, and a year later he, too, was diagnosed with Parkinson’s disease. In his mind, it must have been communicable. However, about 1 million people in the USA have Parkinsonism, mostly people over 60. The chance that the person purchased the home from someone with Parkinson’s and also would acquire the disease is not so unreasonable, given the number of people who buy homes and the prevalence of Parkinson’s disease. In addition, there are thousands of other diseases that both buyer and seller might have had coincidentally. The chance that at least one of those diseases could have occurred in both buyer and seller is high. The clincher here was pointing out that the spouses of patients with Parkinson’s disease do not have a higher incidence of the disease than those not married to someone with Parkinson’s. One of the biggest mistakes in research is confusing correlation with causation.

8.  A study indicated that smiling a lot is correlated with a longer life. Should we then go around forcefully smiling at everyone like the Burger King king? Maybe good health induces people to smile more.

9. If people who take Dynamo MaxiForte vitamins have a lower risk of illness, is it because of the vitamins or because they take care of their health needs in other ways, too, such as exercise and a balanced diet?

10. Teenagers who spend a lot of time texting and on social network websites have a higher incidence of sex, stress, substance abuse, depression, and fighting. Should texting therefore be decreased? Which variable causes which?

The medical and popular literature is rife with examples of confusing correlation with causation. One must be on the alert not to confuse the two.

Medical School Curriculum, medicine,allergy, immunology,asthma, Microbiology

New MedMaster Editions in Microbiology and Critical Care


This best-selling, updated approach to clinical microbiology, brims with mnemonics, humor, summary charts and illustrations; includes all the classic and emerging infectious diseases, with a brand new chapter on the SARS-COV-2 virus, its diagnosis, treatment and immunization. In regular, spiral-bound, or ebook format. ISBN 9781935660484


The new second edition of this best-seller includes a separate chapter on the diagnosis and treatment of COVID-19 in critical care settings. Now in ebook format.

Medical School Curriculum, medicine,allergy, immunology,asthma, Uncategorized

New MedMaster Titles in Genetics and Hematology


The burgeoning field of Genetics is a complex and formidable topic for the student and practitioner. It is easy to get lost in the forest for the trees since genetics lends itself anywhere from a basic foundation of DNA and its parts, to a more complicated and nuanced understanding of how these parts work together, what happens when things go wrong, how to diagnose and treat genetic disorders, and the latest advances and areas of hope in genetic research.

Clinical Genetics Made Ridiculously Simple presents a way to rapidly visualize the field as a whole, including basic genetics, chromosomal abnormalities, epigenetic disorders, cancer, screening tests, gene sequencing, CRISPR, COVID-19 immunization in relation to genes, homeobox genes, and changing approaches to the clinical diagnosis and treatment of genetic conditions.

The author builds from the basics of genetics and DNA, an understanding of how our genetic material functions, what it means to have a genetic defect, what we presently know about these defects and newer therapies for these problems. Each topic is carefully taught, one step at a time, so that the student is never lost, all in 112 pages! $24.95.


Clinical Hematology Made Ridiculously Simple is a brief, clear, practical overview of the range of hematologic disorders, with their diagnoses and treatments, all in 85 pages. The topics include the Complete Blood Count (CBC), disorders of red blood cells (the anemias, iron overload, polycythemia), platelets and blood clotting, white blood cells and the immune system, the leukemias and other hematologic malilgnancies, and blood transfusion. $24.95.


New Critical Care Book from Medmaster

Critical Care and Hospitalist Medicine cover

A thorough guide to the treatment of hospitalized patients in critical care situations. Treatment of pulmonary dysfunction; ventilators and respiratory failure; cardiac, hematologic, GI, kidney, and acid-base disorders; drug overdose, and neurologic emergencies. For further information, see the MedMaster Critical Care page.


Cardiac Drugs low resCardiac PE cover









RHEUMATOLOGY from cover Low Res

Consciousness mrs Lo Res cover




ECG Interpretation Made Ridiculously Simple, by M. Chizner, MD
Clinical Genetics Made Ridiculously Simple, by S. Goldberg, MD

bedside manner, Medical School Curriculum, Uncategorized

Medicine’s Alternative Universe

luckyby S. Goldberg, Med’Toons, Medmaster

An alternative universe is an unseen dimension. When we round and enter the patient’s room, we don’t experience this hidden dimension, just our own world with its medical technicalities.

The hidden dimension is the hospital experience from the patient’s point of view. The patient is not necessarily thinking what the therapist is thinking. I entered this dimension recently after undergoing coronary artery bypass graft (CABG) surgery.  Here are my impressions of the physician’s dimension as opposed to the patient’s dimension during evaluation and treatment:

On being wheeled in a bed to angiography and by-pass surgery that night:
PHYSICIAN: Wheel the patient to the procedure room, adequately sedated.
PATIENT: Nervous; too late to change my mind. As one patient put it “Imagine someone sawing your chest in two and pulling you asunder and then doing some crazy shit to your heart?”  Lying in bed, I don’t have to do any of the wheeling. I’m a VIP from Hell.

Immediately post operation:
PHYSICIAN: Family visitations OK in ICU.
PATIENT: Family scared looking at me recovering from anesthesia. They heard a lot of moaning (which I don’t remember) and thought I might die. I can’t engage in meaningful conversation with them. I don’t look so great the rest of the hospitalization either.

PHYSICIAN: After admission to ICU; remove endotracheal tube (I don’t remember that); monitor vital signs; chest tube should be draining; Foley catheter in place; measure urine volume; IV drip with correct medication flowing at an optimal rate; nasal cannula in place with adequate flow; arterial line from angiography remains in place in groin in case arterial access is needed.
PATIENT: Groggy; pain on respiration largely from chest tubes; have to stay still and supine so as not to disrupt arterial line in right groin. Uncomfortable. I’m used to turning from side to side when I sleep. Can’t do that now.

During 6 days of hospitalization:
PHYSICIAN: Throughout each night, draw blood tests; check oxygen saturation; give medication; check BP, pulse and ECG.
PATIENT: At 3AM every night? Can’t sleep well as is, especially with the background noise and light; try sleep mask and ear plugs; can’t find good sleeping position; have to frequently call nurse to adjust body position; after a few days, need to sleep in chair part of night. So many pills; should I take them all at once or one at a time? Better take one at a time so I don’t choke. What if I arrest? Would they give me chest compressions with this fresh chest wound? Bed pan no fun. You never hear about bed pans in movie plots.

PHYSICIAN: Respiratory therapy – instruct patient how to use volumetric spirometer; administer respiratory inhalant in the middle of the night.
PATIENT: The respiratory therapist is encouraging, but I’m not going to break any Olympic records for volume of inspiration with this spirometer.  Inspiration with the device difficult due to coughing.

PHYSICIAN: Have patient sit in chair, not in bed all the time.
PATIENT: Need warm blankets, since I’m cold. The staff is busy. Not me. Nothing of interest on TV. I specialize in staring into blank space. Can’t work; depressed. Life is accelerating downhill. What about my family? My work? I don’t want to be a burden.

PHYSICIAN: Ambulate patient after 1 day.
PATIENT: Legs feel heavy; hard to stand or walk; in danger of fainting; need assistance in walking short distances, with shuffling. Need a walker; who, me? I’m a patient now!  I think the only difference between being sick and dying is that you don’t get better with dying. I’m walking a little better each day.

PHYSICIAN: Give patient colchicine to reduce cardiac inflammation.
PATIENT: Colchicine causing diarrhea. Hard enough getting out of bed with assistance to go to toilet, and, with all these IVs, need my butt wiped by the nurse.

PHYSICIAN: Time to remove 2 of the 3 chest tubes on day 2; leave one of them in, maybe until tomorrow, since there still appears to be significant fluid in the lungs.
PATIENT: Please take out that last tube tomorrow so that I can breath better with less pain.

PHYSICIAN: Surgery group says chest incision looks good.
PATIENT: It may look good, but it feels more like in the Alien movie before the alien burst from the chest. I guess it’s “better to look good than to feel good.” But I’m glad I’m still above ground. I’m growing a beard; look scruffy and old.

PHYSICIAN: Apply automatic inflatable cuffs pumping continually on calves to help prevent clotting.
PATIENT: Helpful, but another restriction to moving.

PHYSICIAN: Take frequent BP readings, with cuff remaining in place.
PATIENT: Cuff causes an irritating blister under my left arm and has to be moved to the right.

PHYSICIAN: Keep IV going.
PATIENT: IV is infiltrating, blowing up around the needle. Will the nurse come? I’m running out of veins. Was that the last vein available? What will they do if I run out of veins!?

PHYSICIAN: Keep controller near patient to control TV, adjust bed, and enable patient to call nurse.
PATIENT: Help, I can’t find the controller. I’m doomed, unless I yell for assistance. Would they come?

PHYSICIAN: Keep track of urine volume.
PATIENT: I find the male bed urinal difficult to use. Which way? Up or down? I wet the gown and bed; hard to pee when supine; need to stand up.

PHYSICIAN: Administer prescribed diet.
PATIENT: Not hungry; ate little.

PHYSICIAN: Do direct stick for arterial blood gases.
PATIENT: More like several painful sticks; apparently harder to get arterial blood than venous blood; also I’m collecting an assortment of ugly purple patches from blood leaking under my skin. I’m looking more like a patient.

PHYSICIAN: Incisions in right leg to get vein for grafting is healing well.
PATIENT: I forgot that I have more incisions.

PHYSICIAN: Take patient down for x-ray.
PATIENT: I’m down in Radiology, but no one is coming. How long will I wait?

PHYSICIAN: Once outside ICU, arrange consultation for the Surgical team, Pulmonary, Internal Medicine, Cardiology, Physical Therapy, Social Services.
PATIENT: I’m losing track of all the consults. Nursing care very good, but more attentive in ICU where there is higher nurse-to-patient ratio. Medical consult passes through quickly. Does he really care, or has the bedside just become routine and impersonal? Does he know anything about me other than the lab values?

PHYSICIAN: Pain Medication PRN.
PATIENT: I don’t want to take any more meds than necessary. Pain improved on removing chest tubes, but have pain in back, shoulders, and neck, maybe from awkward sleeping position or the surgery itself. Maybe just Tylenol.

PHYSICIAN: Discharge patient, 6 days post-op.
PATIENT: On 11 different medications!!?? Discharge group conference discussed diet, activity, nursing and physical and occupational therapy visitations for 2 weeks, followed by cardiac rehab in 1 month post-discharge. Regarding depression, the group answered any questions and pointed out that I would feel better in time. They did a good job.

Start cardiac rehab 1 month post-op. Exercising more in Rehab; feeling better than I have in a long time 2 months post-op. I am grateful for a new heart. Another benefit: weight loss.

I wrote this blog entry to remind the student and physician that there is another dimension to making rounds, that of the patient’s feelings and point of view. Regretfully, empathy with the patient often diminishes in the latter years of medical school, probably due to lack of time and the mass of technical information that has to be absorbed, in addition to the stress of being personally involved with patient and family. Rather than quickly passing by the bedside on rounds, sit down for a minute with the patient to empathize at the patient’s level. That is also therapy. Do you know who your patient is? Is he/she just “the CABG in room 612?” The patient “won’t care how much you know until they know how much you care.”

Allergy, asthma, Complementary and Alternative Medicine (CAM), Immunology

Two New Medmaster Books: 1. Alternative Medicine 2. Allergy/Asthma


Are You Afraid of Snakes? A Doctor’s Exploration of Alternative Medicine, by C. Scott Mahan

The many books comparing alternative medicine to Western medicine tend to be biased in one direction or the other. Are You Afraid of Snakes? A Doctor’s Exploration of Alternative Medicine offers a balanced view. C. Scott Mahan, M.D., an infectious disease specialist, is co-author of the best-selling “Clinical Microbiology Made Ridiculously Simple.” Are You Afraid of Snakes? describes his 5-year medical journey from Africa to Appalachia, as he encounters many alternative approaches to medicine (voodoo, naturopathy, homeopathy, chiropractic, acupuncture, hot yoga, barefoot running, performance enhancing drinks, titanium necklaces, magnets, hypnosis, detoxification diets, and ayurvedic medicine). Dr. Mahan relates his personal and often humorous experiences in the dual worlds of alternative and Western medicine. He offers an unbiased analysis and opinion of the differing approaches to medicine. 257 pgs; ebook $9.99; print book $16.95.


Allergy and Asthma Made Ridiculously Simple, by Massoud Mahmoudi


Allergy and Asthma Made Ridiculously Simple is a brief, clear, and practical guide to the diagnosis and treatment of allergies and asthma. Dr. Mahmoudi practices internal medicine, allergy, and immunology in California. He has published or edited numerous scientific papers and 9 books related to allergy and immunology, including the best-selling “Immunology Made Ridiculously Simple.” He was a medical columnist for local newpapers and the San Francisco Chronicle, has spoken locally and nationally on allergy and immunology, and appeared on local television and Fox News. Dr. Mahmoudi is currently president of the American Osteopathic College of Allergy and Immunology and on the faculties of the University of California San Francisco, Rowan University, and Touro University. 72 pgs; $22.95.


New Medmaster Editions 2016

“And how long have you been, in my opinion, evil?” (From Med’Toons, by S. Goldberg, Medmaster)

Medmaster is pleased to announce the following new editions:

Nelson: Psychiatry Made Ridiculously Simple (Ed. 5). Includes the newer DSM-5 terminology in the diagnosis of psychiatric illnesses.

Board Reviews Books:
Carl: USMLE Step 1 Made Ridiculously Simple (Ed. 7)
Carl: USMLE Step 2 Made Ridiculously Simple (Ed. 6)
Carl: NCLEX-RN Made Ridiculously Simple (Ed. 4)

Each Board review book presents the material in a rapidly read chart format, plus Internet links to 1000+ review questions.

Rapid Learning

Pattern Recognition In Diagnosis

XBalloon-passed gas

Previous blogs have discussed memory techniques for rapidly learning and remembering information in medical school:

•  Understanding

•  Visualization

•  Ridiculous Associations

•  Substitute Words and Pictures

•  Ditties

•  The Linking Method

•  The Peg Method

•  The Memory Palace

•  Chunking

•  Acronyms

•  Hands-On

Apart from these memory methods, there is another aspect of learning that requires more time to acquire, the ability to quickly recognize disease patterns; this depends on experience.

Often a patient presents with a number of symptoms and signs that may all point to one particular disease; or they may be the result of more than one disease; or some signs and symptoms may be red herrings.  Without experience, there may be a tendency to create a differential diagnosis that is too large or too small, and without proper assignment of correct probabilities to the various potential diagnoses.

For instance, my wife not infrequently experiences headaches in the middle of the night. When I look up the differential diagnosis for this in one of the computerized programs for differential diagnosis, the leading diagnosis comes up as “massive intracranial hemorrhage.” Obviously, this is not true, but the computer program spins this out because the data was collected from hospital admissions, not outpatient visits.  Someone admitted to the hospital with headaches arising in the middle of the night likely has something more serious than someone who is not admitted.

The ability to correctly formulate a differential diagnosis depends on the physician’s experience — whether it is outpatient or inpatient, and even which area of the country or world, where certain diseases are more prevalent than in other areas.  Gaining experience  requires time. That is why the medical student’s differential diagnosis is often so long, and not necessarily listed in order of disease probability.  Eventually, though, the physician learns to quickly determine the most likely diagnosis, based on known disease patterns.  It is important, though, that the physician does not become sloppy and superficially misinterpret patterns by rushing to a diagnosis in the midst of a busy office (or, to save time, simply adopt a shotgun approach, ordering unnecessary tests that may be invasive or expensive).

Humans are expert in recognizing patterns, but often come to the wrong conclusion when they read too much into a pattern (e.g. a face on a pizza).  The ability to efficiently arrive at a medical diagnosis comes with learning on a longer time scale than the memory techniques listed above.

Medical School Curriculum, USMLE

Should USMLE Step 1 Be Eliminated, Modified, Or Open-Book?

“Now this shouldn’t hurt a bit!”
From Med’Toons, by S. Goldberg, Medmaster
At first glance, Step 1, which emphasizes basic science knowledge and is taken after the second year of medical school, would seem necessary to insure that medical students have achieved the proper level of knowledge to proceed in their education.  However, there is another consideration.

I cannot help but notice the great amount of time spent by students discussing how to pass the medical Boards; students are compelled to spend a great deal of time in rote memorization of esoteria for the exam; otherwise they may not pass.  In my view, this emphasis interferes with the need for students to acquire a proper understanding of the topics discussed in the first two years, understanding that is vital in taking care of patients.

Today, it is relatively easy to electronically search for isolated points of information through apps and the Internet; there is less need for rote memorization, which computers do best, and greater need for understanding, which humans do best.  Despite the information explosion, surely there is less need to memorize so much and greater need to promote understanding of the clinical material as a whole.

Even the best physicians may have trouble with questions on the Boards. We would like to gear medical education to turning out the best physicians.  But what constitutes an excellent physician?:

• Most cases a physician sees are common situations rather than zebras.  Good medicine is largely a matter of applying common knowledge and principles to diagnosis and treatment, without getting sloppy, rather than coming up with a roundsmanship coup. The excellent physician does not, to save time, routinely order, in a shotgun fashion, all manner of rare, invasive, and expensive low-yield tests.  Nor does the excellent physician hastily rush to decide on a diagnosis based on a too-quick, superficial initial impression. The best physician is not necessarily the one who has the greatest knowledge base, but the one who consistently and meticulously applies common knowledge.

• Patients do not care so much about the physician’s medical school or residency diplomas as they do care about how the physician responds to them as individuals, whether the physician is compassionate, and allots the patient the necessary time.  “Patients do not care how much you know, until they know how much you care.”  This aspect of medicine is also important, just as is the knowledge base.

• The good physician, unless there is an emergency, schedules reasonable office waiting times, promptly notifies patients of lab results, follows up on the patient’s progress, and adopts more than just a cookbook approach to diagnosis and treatment. Medical education needs to emphasize understanding of important concepts, as well as familiarity with where and how to search for isolated points of information, which have grown too large for anyone to remember.  This is not emphasized on the Boards.  Emphasizing understanding, something Medmaster has focused on for the past 34 years, may seem to be a minimalistic approach to education, but in fact it is a maximal approach, insuring that the student acquires the greatest degree of understanding. Every patient is different, and a cookbook approach may not work for all patients; understanding  what one is doing is critical to good patient care.

So, should Step 1 of the USMLE be eliminated, or modified? Perhaps Step 1 should be an open-book exam; this would more resemble everyday practice, where physicians now have ready access to point-of-care information. What do you think?

Career Choice, Uncategorized

Steven Goldberg – In Memorium

Last week Steven Goldberg (no relation), a former student of mine at the University of Miami School of Medicine, passed away of lymphoma at the age of 42.  After 25 years of my teaching at the U of M, his name stands out in my mind, not because of similarity of name, but because of his brilliance and character.  He was a true mensch.

Steve was born with transposition of the arteries, which required surgical correction.  When he advanced in medicine, his goal was to become a pediatric cardiac surgeon and offer to other children what had been provided to him.  He did just that, training at the same institution that had operated upon him as a child.  He specialized in difficult cardiac procedures in children, including the kind of congenital defect that he had, as well as cardiac transplantation.

You can gain a better glimpse of his character through the YouTube video he prepared for LeBonheur Children’s Hospital last year. Within only a few days of his passing, there were hundreds of facebook postings by people whose lives he had touched.

Steve was also a skilled artist who illustrated significant parts of my books on Clinical Physiology Made Ridiculously Simple and Med’Toons. Here are three of my favorite cartoons that he drew:

Emphysema in wolves
From Med’Toons, by Stephen Goldberg, Medmaster

T-helper cell function in the immune system.
From Clinical Physiology Made Ridiculously Simple, by Stephen Goldberg, Medmaster

Steve will be greatly missed.  He was the personification of the ideal physician.


Drawing The Patient Into the Decision-Making Process

From Med'Toons, by S. Goldberg, MedMaster
From Med’Toons, by S. Goldberg, MedMaster

Should the patient and family participate in the decision-making process as to whether or not to pursue an aggressive course of therapy?

Of course, there are those patients who say “Whatever you think would be best doc.”  And there are others who are so mentally incapacitated as to not be able to render an intelligent decision.

But what if a patient wants to help decide on the course of therapy? There are two points of view.  There are physicians who feel that patients and family should not participate in decision-making in aggressive treatments, such as surgery, radiation, and chemotherapy, as they are too emotionally involved and may not think rationally.  I feel otherwise.  Apart from the patient having the right to agree or not agree to a particular treatment, there are situations in which the patient may be in a better position than the physician to decide.  For instance, say a patient has a tumor of the arm and the statistics indicate that there is a 90% chance of survival if the entire limb is removed, but only a 70% chance of survival if the tumor is removed locally, but leaving the function of the arm intact if successful.  What should one do?  Leave the decision up to the physician, or seek the patient’s opinion?  The physician may opt to remove the arm to improve the chances of survival but the patient may want to take the gamble, in order to keep a functioning limb. The patient’s choice may well be the better one; it suits the patient’s individual needs.  The patient and family may be willing to gamble, while the physician may not.

If the patient and family are well-informed of the facts, the therapist should encourage their participating in the decision-making. The patient and family not only have the right to do so, but their input may be helpful, even invaluable, in making the right decision.