On Medical Symbols

A little on the design of medical symbols

(***Reference links open in new windows***)

If we could prove medical symbols to have design rules it'd back up the work that found icons designed by SMEs were easily recognised by non-SMEs. Sure. However, while examining the peripheries of the etymologies of symbols in health care I determined some discrepancy between that that I'd been fed as history, and what history actually records.

This blog input examines the simple snake and staff concept. There's a lot here for my own learning so jump down the titles by all means, but at what point does the history / etymology of a symbol or word become hearsay?

Given in my earlier piece on the Red Cross and the fact my colleagues were satisfied that it derived from the Swiss flag and was, therefore, a-religious and that Islamic faiths were crass to take offence based on the barbarity of the Crusades, I fear that hearsay in the right journal or ancient book (translated by a short-sighted geezer with 6 languages under his belt) can become truth: faith even?

Aaaron's staff

When I joined the RAMC the tradition was taught that the snake and rod on our Corps' badge originated from the Biblical Book of Genesis where Moses' mate, Aaron, threw down his staff at the feet of the Pharaoh and it turned into a snake (as instructed by God). The pharaoh's sorcerers threw their own staffs down in reply and they too turned into snakes (clever fellows, the lot of them). At that point, with the sorcerers up on points by sheer quantity, Aaron's staff cheated and ate all the other bloke's efforts making it one-all.

I have some trouble with this because I'm sure the Pharaoh, the sorcerers and Aaron were busy blokes – yet alone poor Moses with all the miracles he had to perform. A snake takes bloomin' ages to scoff even a fluffy baby chicken: I can't see a brace of snakes being devoured without consideration to the clock and some massive overtime payouts from the Pharaoh.

As a Tom, we sniggered a lot: the double-entendre of snakes and rods / staffs is funny enough to a late adolescent, but to think of one wrapped around another in those heavily heterosexual days, now that was taboo!

The staff (the rod) of Aesculapius.

A staff or rod with a snake curled around it: the staff of Aesculapius (also called Asklepios), the ancient mythical god of medicine.

In reality, Asklepios may have been renowned for his gentle, humane remedies and treatment of the mentally ill. His followers established temples called asclepions, temples of Asklepios, temples of healing.

The greatest was south of Corinth, Greece where the sick had to spend a night while the proper remedies were revealed during a dream to the priests of the temple and the cured had to make a suitable sacrifice (usually a rooster) to the god.

Asculapius had a number of children including Hygieia, the goddess of health (from whose name comes the word "hygiene") and Panaceia, the goddess of healing (from whose name comes the word "panacea" or, universal remedy).

Definition of Medical symbol. Medicine.net. Retrieved 29 November 2006 from http://www.medterms.com/script/main/art.asp?articlekey=7863

According to Answers.com, his first teacher was the centaur Chiron. When he became so skilful in healing that he could revive the dead, Zeus killed him. Apollo persuaded Zeus to make Asclepius the god of medicine. I'll not add anything to that because Zeus obviously needed Asklepios' professional help!

The worship of Asclepius is believed to have originated in Thessaly. Temples were built to him at Epidaurus, Cos, Pergamum, and later Rome, where his worship spread after a plague in 293 B.C. Treatments, including massage and baths, were given to the sick (did we try this in 1665, I wonder?).

Back to the snakes. In honor of Asclepius, snakes were often used in healing rituals.
Non-poisonous snakes were left to crawl on the floor in dormitories where the sick and injured slept. (Why???)

Starting about 300 BCE, the cult of Asclepius grew very popular. Pilgrims flocked to be healed. They slept overnight and reported their dreams to a priest the following day. He prescribed a cure, often a visit to the baths or a gymnasium at the equivalent of £12 a head, I'll bet.

Asclepius. Answers.com. Retrieved from http://www.answers.com/topic/asclepius 29 November 2006.

Meanwhile, at www.cwru.edu/artsci/dittrick/murals/stories.htm Asklepios is painted being taught by Cheiron and with his serpent out on show.

Symbology

The Rod of Asclepius symbolizes the healing arts by combining the serpent, which in shedding its skin is a symbol of rebirth and fertility, with the staff, a symbol of authority, befitting the god of Medicine. RSMs and some SSMs lacking in presence still carry sticks to resemble authority – mind, as we can't hit the Toms with them any more they're becoming less popular.

Paintings Above: The first panel is titled Asklepios Taught by Cheiron, here Asklepios is being taught the art of healing by Cheiron, the greatest of centaurs.

The second panel, titled Asklepios Beloved Physician. The origin of the medical symbol, a snake-entwined staff is depicted.

The snake wrapped around the staff is widely claimed to be a species of Rat snake, Elaphe longissima, also known as the Aesculapian (Asclepian) snake. It is native to south-eastern Europe, Asia Minor, and some central European spa regions, apparently brought there by Romans for their healing properties. (Ah, so the snakes have healing properties – now this crops up again later, so take note, yeah!)

Rod of Asclepius. Answers.com. Retrieved from http://www.answers.com/topic/rod-of-asclepius 29 Novemebr 2006.

Asclepius himself, in traditional Greek mythology, was reputed to have the blood of Medusa in his veins (and she had snakes for hair and turned a man's rocks when he looked up on her). The blood that flowed on Medusa's left side was said to be fatal poison. The blood from her right side was beneficial. (Mythology's great – who actually tried this out? "Eh, ma'am, let me slit you open so I can test your blood because you're pretty weird and bound to be have magical properties…")

Asclepius was also known as Ophiuchus, the son of Apollo, to the ancient Greeks. In early Christian theology, the constellation Ophiuchus was associated with Saint Paul holding the Maltese Viper.

In Hebrew theology, a similar symbol, Nehushtan, is mentioned in the Bible in Numbers 21:4–9. Attacked by a plague of snakes in the wilderness, Moses holds up a serpent made from bronze so that the Israelites might recover from the bites. The serpent itself was seen as a powerful healing tool. (And Moses crops up with snakes and rods again, too, of course with his mate Aaron and the damaging of the Pharoh's property).

Rod-of-asclepius. Answers.com. Retrieved from http://www.answers.com/topic/rod-of-asclepius 29 Novemebr 2006.

According to sources, in the Torah, the Israelites were complaining about their problems in the desert somewhere near Punon. God, angered at their lack of faith and ungratefulness, sent poisonous snakes among them as punishment. It then goes on to describe Moses, who had prayed in order to intercede on their behalf, being told by God to make a brass snake so that the Israelites merely had to look upon it to be cured from the snake bites.

This, however, may be a subtle play on words: heb. נחש (nachash) means serpent while נחשת (nachoshet) means brass or bronze.

Nehushtan. Answers.com. Retrieved from http://www.answers.com/topic/nehushtan 29 November 2006

Ono Nehushtan: the dual -an ending specifies that the idol was of two snakes upon the pole, the familiar entwined snakes on the staff that survived in Hermes' caduceus and the single snake on the staff of Aesclepias."

Nehushtan. Answers.com. Retrieved from http://www.answers.com/topic/nehushtan 29 November 2006

Back to Snakes

I'm of the opinion snakes have been known to be pretty venomous critters throughout our history and folk-lore. Adam and Eve we even double-crossed by a serpent who became an evil devil. Snakes are serpents. Serpents are monsters. So where's the healing bit from?

I guess the practice of using snake venom in controlled doses must have been discovered early in our evolution and we could see that as the healing power of snakes? Imagine conjuring up a great trick to impress one's self as a sorcerer to work closer to the Pharohs' lovely daughters and poisoning someone enough to have you called to heal them? Slip the anti-venom (seen milked bravely from a wriggling serpent) into their Horlicks, and presto! One healed gadgy and dinner with the girl.

According to The Society Of Cardiopulmonary Technology Nz Ltd, the snake as the symbol of medicine goes back to a legend claiming that there was a man who needed to go into a hospital. The doctor at the entrance thought he was fatally ill and did not accept him. As this was a tradition (must have been QE at Portsmouth?) the patient knew that he was going to die opted to commit suicide to get it over with immediately.

He was uncertain of a method, though. As left the hospital, he saw a snake drinking milk from a cup and spitting the milk back out in the same cup. (I've got something to say on this in a moment, but let's not ruin the story, eh?)

The patient, thinking that this milk must be poisonous, grabbed the cup and drank the milk. To the surprise of the man, and the doctor (who was really keeping an eye on the patient), the patient started getting well.

It was realised that one way of fighting illness was to take the right amount of venom in the body, vaccination!! The snake was then made the symbol of medicine.

Medical Trivia. The Society Of Cardiopulmonary Technology Nz Ltd. Retrieved from http://www.sct.org.nz/Medical%20Trivia.htm 27 November 2006.

Okay. A snake drank from a cup. Now, I've seen a dog drink from a glass of beer (a long time in Colchester as a pup) and hedgehogs drink from a saucer, but a bloody snake happens across a cup of milk? What else was it doing, reading today's edition of the Telegraph? As it happens, this is the only reference to this theory I could find. I'm satisfied the idea of a hospital probably means this theory is MUCH younger in the World timeline than the others examined here and probably originates from all that fresh air enjoyed in NZ! It just goes to show how one needs to be cautious of history…

More on Caduceus

I first came across the term caduceus during a (fantastic) trip to South Africa in 2000 when I was presented a single-winged caduceus as an honorary SAMHS medic after helping with the export of BATLS there. The doctors got double-winged versions. Nurses got confused!

The symbol of two intertwined snakes appeared early in Babylonia and is related to other serpent symbols of fertility, wisdom, and healing, and of sun gods.

A herald's wand or staff, especially in ancient times came from Greek Mythology.

A winged staff with two serpents twined around it, was carried by Hermes. It served as a badge of protection for ancient Greek and Roman heralds and ambassadors. It was originally depicted as a rod or olive branch ending in two shoots and decorated with garlands or ribbons; in later iconography the garlands became two snakes and a pair of wings was attached to the staff to represent Hermes' speed. The caduceus was adopted as a symbol of physicians because of its similarity to the staff of Asclepius.

Caduceus. Answers.com. Retrieved from http://www.answers.com/topic/caduceus29 November 2006.

In other words, there's a theme we're still missing here about the commonality of the symbols of the rod and the snake between all the main stories of Aaron and Asclepius. Is it a coincidence their names each commence with the letter 'A', and that names of the ancients are known to change according to the traditions of the translators?

In the United States, the staff of Asklepios (the Asklepian) and a double serpent–entwined staff with surmounting wings (the caduceus) are both popular medical symbols.

The latter symbol is often designated as the "medical caduceus" and is equated with the ancient caduceus, the double serpent–entwined staff of the Greco-Roman god Hermes (Latin, Mercury).

Many physicians would be surprised to learn that the medical caduceus has a quite modern origin: Its design is derived not from the ancient caduceus of Hermes but from the printer's mark of a popular 19th-century medical publisher. Furthermore, this modern caduceus became a popular medical symbol only after its adoption by the U.S. Army Medical Corps at the beginning of the 20th century.

Wilcox, R., (2003). The Symbol of Modern Medicine: Why One Snake Is More Than Two 15 April 2003 HISTORY OF MEDICINE Volume 138, Issue 8, Pages 673-677, retrieved 29 November 2006 from http://www.annals.org/cgi/content/abstract/138/8/673

Now, call me picky, but why would a publishers use the symbol? I wonder if, were we to investigate this further, the publishers wouldn't turn out to be publishers of medical books and journals? You don't think? Look back at the idea of the Red Cross and the flag of Switzerland!

Worms

As noted in this thread, the caduceus (medical symbol) may not be a staff with snakes, but rather guinea worms (Dracunculus medinensis ) wrapped on a removal device. (See see Answers.com at http://www.answers.com/topic/dracunculiasis)

The reason these little critters were adopted by the medical profession as their symbol is because they represent one of the first "treatable" parasitic afflictions of man. It was one of the first endosomatic parasites that were removable by primitive means, i.e. non-surgical. We now know a whole lot more about these worms than we did 100 years ago.

Morris, K., (1996). Medical symbol - African parasite? Retrieved from http://www.bio.net/bionet/mm/parasite/1996-November/001821.html29 November 2006.

Wait one: why would this reference claim the early treatment of this worm infection was the original caduceus and then state the, "100 years ago" in the same context? I know the worm thing crops up often enough, but do these authors appreciate the 2300yrs of history here – not to mention the trip back to Moses' time of Pharaohs and sorcery, which must be reckoned to be 4000yrs ago, at least – when the stories were first recorded, never mind occurred?

However, the wormy thing is also reported in the BMJ in a letter from Mr D A Dyson British Medical Journal Volume 286 1 January 1983. Retrieved From http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=1546616&blobtype=pdf 29 November 06 and at Answers.com (I'm beginning to like this resource, you can tell).

Why keep the snakes?

"…We liked Dr. Paparounas's suggestion but would prefer the combined term Asklepian iatrosema."

"However, we believe that Dr. Newman's suggested introduction of a third serpentine symbol consisting 2 snakes in a right-handed helix mimicking DNA would be entirely counterproductive. After all, the DNA of mice, rats, and monkeys is in essence very similar to that of humans, and we therefore champion the Asklepian symbol because it reminds us of the essentially humanistic nature of medical practice".

"An inscription found at the Asklepieion of Athens specifies the Asklepian commitment: "These are the duties of a physician ... he would be like the God, savior equally of slaves, of paupers, of rich men, of princes and to all a brother such help he would give."

"he Asklepian tradition emphasizes integrity, sacrifice, compassion, and universal access to health care. People are most equal in their capacity for illness and suffering. Thus, physicians must seek to practice their craft without primary regard for the social status of their patients, personal advancement, or financial rewards. As Sir William Osler wrote, "The practice of medicine is an art, not a trade; a calling, not a business; a calling in which your heart will be exercised equally with your head"…

The Reply to Wilcox (2003) in HISTORY OF MEDICINE 17 February 2004 Volume 140 Issue 4 Pages 311-312 retrieved from http://www.annals.org/cgi/content/full/140/4/311-c 29 November 2006.

Mind you, doctors do charge an awful amount of money for their calling, don't they?!

The Star of Life

Okay, building on this common symbol with uncommon background, let's just relate this to the Red Cross muse in an earlier posting. The IRRC have craftily suggested / adopted a Red Crystal, which is a diamond but called "crystal" to keep the IRRC title alive. Clever stuff.

Elsewhere, however, another attempt to produce a culturally sensitive symbol of acute medical care has been adopted. We see it all the time on private ambulances (in particular). Indeed, when I attended a BTLS course I thought the symbol was their trade mark. Not so! See below:

The Star of Life is a blue, six-pointed star with the Rod of Asclepius in the center, originally designed and governed by the U.S. National Highway Traffic Safety Administration (NHTSA). Internationally, it designates emergency care units and personnel. A similar Orange star is used for search and rescue personnel.

History

The Star was created in 1973 by Leo R. Schwartz, Chief of the EMS branch at the NHTSA to avoid legal problems related to the use of derivatives of the Red Cross (like orange cross, green cross, etc.). The Star of Life was registered as a certification mark on February 1, 1977.

Symbolism

The six branches of the star are symbols of the six main tasks executed by rescuers all through the emergency chain:

The first rescuers on the scene observe the scene, understand the problem, identify the dangers to themselves and the patient(s), and take appropriate measures to ensure the safety on the scene (circulation, electricity, chemicals, radiations, etc.).
The first rescuers call for professional help.
The first rescuers provide first aid and immediate care to the extent of their capabilities.
The EMS personnel arrive and provide immediate care to the extent of their capabilities.
The EMS personnel proceed to transfer the patient to a hospital for specialized care. They provide medical care during the transportation.
Appropriate specialized care is provided at the hospital.

Star of Life. Answers.com. Retrieved from http://www.answers.com/topic/star-of-life-1 29 November 2006.

Personally, I think the six main tasks bit is flowery codswallop and totally irrelevant: probably manipulated into the medical consciousness as some lame pneumonic for an overly run doctor's appreciation society-style course. Obviously, I couldn't allude to the ATLS there!

The Snake – Which snake?

Let's go back to that doctor watching a snake drink from a cup (and we know who did the Controlled Drugs Check that shift, don't we!) This is a coincidence of species, I believe, that may only be random waffle but it could make the main motivational guts of an "oh, yeah, that's so unreal I must pass it on to all my contacts and spread the Trojan hidden in the code" chain email.

The fact the snake depicted in the medical symbols is widely believed to be a Rat Snake is interesting (based on the geography of Greece 300BC), but even more astounding is that a Milk Snake (from Central America) looks like a Corel Snake – a deadly snake I encountered on a trip to Belize. ('Chakka' - you still alive?)

You need to have quick wits to spot one from the other: a Milk Snake (top pphoto) from a Coral Snake (btm photo): a real edge of death experience. As a medical analogy the power of life or death reliant on observation, experience, and intellect combined with a cool head is a pretty strong one.

[That's quite profound for me and you should use it in your own references in future.]

From Answers.com: " …Some milk snakes have a striking resemblance to a coral snake and use this mimicry (a type of mimicry called Batesian mimicry) as a form of self defence…"

Milk Snake. Answers.com. Retrieved from http://www.answers.com/milk%20snake29 Novemebr 2006.

The Corps' Snake (RAMC)

Whether the safe or deadly snake, the idea of the red, yellow, and black snake being even vaguely related to the Rat Snake entwined around our Corp's staff is faintly – though in only a quirky way – kind of amusing. If you think on it, the bands of colour are not a long way from the dark cherry, old gold, and royal blue of our Corps' colours! Another canny coincidence ruined only by the poor Ishihara results of the bloke that designed the belt for Queen Elizabeth, The Queen Mother (GRHS).

Back to the research

"…Six domain experts were given 50 common textual mammography findings and asked to draw how they would represent those findings graphically.

The [non-domain experts] multiple sorters were able to reliably group graphics into similar groups that strongly correlated with underlying domain concepts. Visual inspection of the resulting consensus clusters indicated that graphical primitives that could be informative in the design of icons were present…"

Payne, P., Starren, N., (2005). Quantifying Visual Similarity In Clinical Iconic Graphics. J Am Med Inform Assoc. 2005;12:338–345.

So, utilizing SMEs to design your symbols might actually increase the chances of non SMEs recognising the common styles between groups of concepts (if not the finite meaning of each icon).

Due to the characteristic of “language-independence”, graphical symbols are regarded as one effective way to convey information across countries…The comprehension test method recommended in ISO 9186 was applied. The test results revealed that the comprehension of the symbols in both countries is generally poor and there is no significant difference between these two countries. The application experience of the users, however, significantly influences the target users’ comprehension. It seems that training would be the indispensable way to ensure effectiveness of symbol application on device user interfaces.

Long, L., Hoelscher1, U., and Gruchmann2, T., (2005) Symbol Comprehension in Different Countries: Experience Gained from Medical Device Area. A. Auinger (Hrsg.): Workshops–Proceedings der 5. fachübergreifenden Konferenz Mensch und Computer. Wien: Oesterreichische Computer Gesellschaft, 2005, S. 81-87.
Retrieved from http://mc.informatik.uni-hamburg.de/konferenzbaende/mc2005/workshops/WS8_B4.pdf 29 November 2006.

A sort-of summary and posing of awkward thoughts for later pondering…

We can all recognise medical signs with the snakes and rods on them based on popular Western and North-African myth and tradition because of a commonality of concept (the themes, or characteristics of the symbols) but don't necessarily need to understand the ACTUAL meaning or etymological origins of the symbols to receive the meaning of the image.

It is likely our cultural learning to recognise the signs doesn't require conscious understanding of their origin but only understanding of the symbols intention in context.

I take it that in the design of icons for learning less thought needs to be given to the abstract of a symbol's origin except in the case of building argument to support the choice of one symbol over another. However, the use of SMEs to scope the design of icons might lead to a higher frequency of recognition as they are likely to be more relevant to the concrete meaning intended.

PS - I know the references are poorly presented, but I'll probably get back to do them properly later...honest. Stop complaining.

Post Script

Considering the medical history of the snake and staff outlined above and the double-meaning of the red cross (ICRC and medical), what is Alpha Romeo up to? Can the car heal itself after despatching a traffic-weary badger? No, it bloody well can't and it costs a fortune, too!

 

 

Images on this page that were not sourced as referenced are from a collection of Internet site images saved without source information. Original contributors are unknown - my thanks and appreciation to them.