Ask Your Doctor About ElephaNNTs

Old joke:

A man, frantically waving his arms in the air, goes to see his doctor.  “What are you doing with your arms”, asks the doctor.  “I’m keeping the elephants away,” says the man.  “But there are no elephants here,” says the doctor.  “See.  It’s working,” says the man.

Alternate version of old joke:

A doctor, believing his patient to having a deep-seeded fear of elephants, advises him to always wave his arms in the air.  “Why should I do that,” asks the man.  “It will keep the elephants away,” says the man.  “But there are no elephants here,” says the man.  “See.  It’s working,” says the doctor.

Just for fun, let’s calculate to elephaNNT of arm-waving.  According to, the average numbers of annual deaths in the United States by animals are:

Bees/Wasps 53.00
Dogs 31.00
Horses 20.00
Spiders 6.50
Rattlesnakes 5.50
Bulls 3.00
Mountain lions 1.00
Sharks 1.00
Bears 0.50
Centipedes 0.50
Alligators 0.30
Elephants 0.25
Wolves 0.10

Assuming that arm-waving is 100% effective in keeping elephants away (maybe if not confronted with a charging elephant), and that the population of the U.S. is 310 million, the NNT of an arm-waving defense against elephants, over a 10-year period, would be almost 125,000,000 — higher than most any drug.

The purpose of this little exercise is to again stress the importance of a frank discussion between a doctor and patient whenever considering a drug, test, or surgical procedure.  In almost every case, there is a trade-off between potential benefits and risks.

We have found that the mere mention of NNT is an effective way to initiate a much needed conversation, if only to introduce the concept — by either the doctor or the patient. 

Another approach, likely to enliven the conversation and lead to a similar result, is to ask, “Yes, but will it keep the elephants away?”