A micromort as a unit of comparing and communicating risk to patients equivalent to a one in a million chance of dying.
Micromorts: How Risky Is It to Go Under Anesthesia?
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
Hundreds of millions of operations are performed every year, and the risk of death is typically around a half a percent, to which patients might say things like, “I could just die as easily crossing the road,” making it clear they really don’t understand the difference in magnitude of risk. One way to communicate risk is by analogy. For example, just going under anesthetic carries about a 1 in 100,000 chance you won’t wake up. How much is that? Well, that’s about the same risk as an expert sky dive. Okay, but that still may be kind of hard to wrap your head around. It’s hard to think in terms of small numbers. Imagine discussing a 0.0017 mile x 0.00227 mile rug. How big even is that? We need more digestible units. Enter the micromort as a unit of comparing and communicating risk to patients.
A micromort is a unit equivalent to a one in a million chance of dying. One in a million is like the chances of flipping a coin, and getting 20 heads or tails in a row––or a little less than the chances of getting a royal flush. But the real utility is to help compare different risks to one another, using the same metric. For example, driving a hundred miles entails about a one in a million chance of death, so that’s one micromort. Scuba diving is like five micromorts per dive; so, each dive is as risky as driving 500 miles. So, now we have a way to directly compare the risk of surgical procedures and common activities.
Giving birth is as risky as driving from NY to LA and then back again, but getting a cesarean is more than twice as risky. Even something like a simple hernia repair carries the same risk of dying as something like sky diving 200 times. Now obviously, sometimes you have no choice, but death from varicose vein surgery or circumcision could probably be avoided. I was surprised to learn that regular horseback riding is about four times deadlier than rock climbing, but getting chemo and radiation for head and neck cancer is riskier than rock-climbing for 500 years, driving 5 million miles, or 5,000 sky dives, etc.
One leading cause of death I really didn’t talk about in How Not to Die is accidental death. We have approximately a one in a million chance of dying just by accident every day of our lives, and about half of that risk is dying in a car crash, based on U.S. averages. Then, there are all sorts of other ways. I am surprised to learn Americans have about a 1 in 200,000 chance every year of dying from a foreign body entering an orifice other than the mouth.
Other things we may want to avoid include climbing Mount Everest––about 30 times riskier than coal mining or base jumping. Trains and planes are actually equivalent over the same distance, but riding a motorcycle is about 50 times deadlier than riding in a car, though cycling to a destination is riskier too: about 10 times as deadly as driving in the near term.
Here’s a good example of how one can use micromort comparisons to help put things in perspective. Certain types of breast implants can cause a rare type of cancer, a type of breast implant-associated lymphoma. You can imagine how scary this is for the millions of women who have implants, but check out the risk compared to the risk of other common activities. Your risk of dying from this kind of cancer is less than a single day of skiing. Now, it’s probably better to die quick on the slopes than all the slow suffering of cancer, and risk of bankrupting your family, but at least it can put the risk of the implant-cancer killing you in context.
Please consider volunteering to help out on the site.
- Ahmad N, Peterson N, Torella F. The Micromort: a unit for comparing and communicating risk to patients. Int J Clin Pract. 2015;69(5):515-7.
- Fry AM, Harrison A, Daigneault M. Micromorts—what is the risk?. Br J Oral Maxillofac Surg. 2016;54(2):230-1.
- Howard RA. Microrisks for medical decision analysis. Int J Technol Assess Health Care. 1989;5(3):357-70.
- Every-Palmer S, Howick J. How evidence-based medicine is failing due to biased trials and selective publication. J Eval Clin Pract. 2014;20(6):908-14.
- Keage HAD, Loetscher T. Estimating everyday risk: Subjective judgments are related to objective risk, mapping of numerical magnitudes and previous experience. PLoS One. 2018;13(12):e0207356.
- Sieber DA, Adams WP Jr. What's Your Micromort? A Patient-Oriented Analysis of Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL). Aesthet Surg J. 2017;37(8):887-91.
- Swanson E, Mackay DR. Why the Micromort Concept Falls Short in Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL) Risk Analysis. Aesthet Surg J. 2018;38(3):NP68-70.
Motion graphics by Avo Media
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
Hundreds of millions of operations are performed every year, and the risk of death is typically around a half a percent, to which patients might say things like, “I could just die as easily crossing the road,” making it clear they really don’t understand the difference in magnitude of risk. One way to communicate risk is by analogy. For example, just going under anesthetic carries about a 1 in 100,000 chance you won’t wake up. How much is that? Well, that’s about the same risk as an expert sky dive. Okay, but that still may be kind of hard to wrap your head around. It’s hard to think in terms of small numbers. Imagine discussing a 0.0017 mile x 0.00227 mile rug. How big even is that? We need more digestible units. Enter the micromort as a unit of comparing and communicating risk to patients.
A micromort is a unit equivalent to a one in a million chance of dying. One in a million is like the chances of flipping a coin, and getting 20 heads or tails in a row––or a little less than the chances of getting a royal flush. But the real utility is to help compare different risks to one another, using the same metric. For example, driving a hundred miles entails about a one in a million chance of death, so that’s one micromort. Scuba diving is like five micromorts per dive; so, each dive is as risky as driving 500 miles. So, now we have a way to directly compare the risk of surgical procedures and common activities.
Giving birth is as risky as driving from NY to LA and then back again, but getting a cesarean is more than twice as risky. Even something like a simple hernia repair carries the same risk of dying as something like sky diving 200 times. Now obviously, sometimes you have no choice, but death from varicose vein surgery or circumcision could probably be avoided. I was surprised to learn that regular horseback riding is about four times deadlier than rock climbing, but getting chemo and radiation for head and neck cancer is riskier than rock-climbing for 500 years, driving 5 million miles, or 5,000 sky dives, etc.
One leading cause of death I really didn’t talk about in How Not to Die is accidental death. We have approximately a one in a million chance of dying just by accident every day of our lives, and about half of that risk is dying in a car crash, based on U.S. averages. Then, there are all sorts of other ways. I am surprised to learn Americans have about a 1 in 200,000 chance every year of dying from a foreign body entering an orifice other than the mouth.
Other things we may want to avoid include climbing Mount Everest––about 30 times riskier than coal mining or base jumping. Trains and planes are actually equivalent over the same distance, but riding a motorcycle is about 50 times deadlier than riding in a car, though cycling to a destination is riskier too: about 10 times as deadly as driving in the near term.
Here’s a good example of how one can use micromort comparisons to help put things in perspective. Certain types of breast implants can cause a rare type of cancer, a type of breast implant-associated lymphoma. You can imagine how scary this is for the millions of women who have implants, but check out the risk compared to the risk of other common activities. Your risk of dying from this kind of cancer is less than a single day of skiing. Now, it’s probably better to die quick on the slopes than all the slow suffering of cancer, and risk of bankrupting your family, but at least it can put the risk of the implant-cancer killing you in context.
Please consider volunteering to help out on the site.
- Ahmad N, Peterson N, Torella F. The Micromort: a unit for comparing and communicating risk to patients. Int J Clin Pract. 2015;69(5):515-7.
- Fry AM, Harrison A, Daigneault M. Micromorts—what is the risk?. Br J Oral Maxillofac Surg. 2016;54(2):230-1.
- Howard RA. Microrisks for medical decision analysis. Int J Technol Assess Health Care. 1989;5(3):357-70.
- Every-Palmer S, Howick J. How evidence-based medicine is failing due to biased trials and selective publication. J Eval Clin Pract. 2014;20(6):908-14.
- Keage HAD, Loetscher T. Estimating everyday risk: Subjective judgments are related to objective risk, mapping of numerical magnitudes and previous experience. PLoS One. 2018;13(12):e0207356.
- Sieber DA, Adams WP Jr. What's Your Micromort? A Patient-Oriented Analysis of Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL). Aesthet Surg J. 2017;37(8):887-91.
- Swanson E, Mackay DR. Why the Micromort Concept Falls Short in Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL) Risk Analysis. Aesthet Surg J. 2018;38(3):NP68-70.
Motion graphics by Avo Media
Republishing "Micromorts: How Risky Is It to Go Under Anesthesia?"
You may republish this material online or in print under our Creative Commons licence. You must attribute the article to NutritionFacts.org with a link back to our website in your republication.
If any changes are made to the original text or video, you must indicate, reasonably, what has changed about the article or video.
You may not use our material for commercial purposes.
You may not apply legal terms or technological measures that restrict others from doing anything permitted here.
If you have any questions, please Contact Us
Micromorts: How Risky Is It to Go Under Anesthesia?
LicenseCreative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
Content URLDoctor's Note
How dangerous are medical interventions in general? Surprisingly, we physicians are a leading cause of death. See Why Prevention Is Worth a Ton of Cure. To see How Doctors Responded to Being Named a Leading Killer, check out the video.
If you haven't yet, you can subscribe to our free newsletter. With your subscription, you'll also get notifications for just-released blogs and videos. Check out our information page about our translated resources.