Decisions based on Perceived Risk can be hazardous to your health.
November 15, 2013
People make decisions based on their perception of risk rather than the actual risk resulting in focusing time, effort and angst on events that may have a limited chance of occurrence. Meanwhile, events that may be far more likely to cause harm are deemphasized or ignored completely resulting in a greater exposure to actual harm.
Paul Slovic , a pioneer in the study of risk perception, believes this most frequently occurs in people lacking knowledge of a subject or who have a feeling that actions or events are out of their personal control. This effect may be span any number of areas ranging from fear of Genetically Modified Organisms (GMOs) , fear of nuclear power, fear of vaccinations or even fear of child abduction by strangers.
What is Risk?
At a fundamental level, one definition of Risk (R) is that it is the product of Frequency (F) and Consequence (C) or R=FxC. It would follow that risk increases as the frequency of an event increases or as the consequences of the event increases. An event that occurs frequently but is of little consequence may therefore carry less risk that an event that occurs less frequently but has greater consequences. For example, driving a car with an engine that frequently stalls may be considered to have less risk than flying a plane with an engine that stalls once.
Perception is reality
Although risk may lend itself to mathematical analysis, it is likely that people make risk-based decisions more by their perception of risk rather than through objective risk analysis. If the latter were the case then people should have a greater fear of driving to the local store than flying to another city because flying can be demonstrated to be far safer than driving. Similar arguments could be made with the fear of child abductions, nuclear power, vaccinations and GMOs.
Less control plus less knowledge equals higher perceived risk
The less we know about an activity the more likely we are to see it as risky. Or so it has been suggested by Paul Slovic who published a frequently cited paper on the subject in 1987 . In the paper Slovic argues that not only are unfamiliar activities seen as more risky than familiar but that actions under our control are deemed less risky than actions over which we have little control.
Returning to the flying versus driving comparison we can see that our lack of control as well and lack of understanding or accepting the statistics on safety compound to create an irrational fear of flying for some people. For any situation where the activity is both unknown and uncontrollable, the perceived risk is likely to be high regardless of the actual risk.
Misdirected focus of attention
The key point is that perception of risk drives decisions related to course of action far more than objective risk assessment. This decision process based on perception instead of reality can lead to taking actions to prevent harm from relatively harmless threats while ignoring threats from overtly more dangerous events. It is why we see worried parents guarding their children at school bus stops to prevent abduction by a stranger but the same parents will let their children ride bicycles without a helmet.
On November 15, 2013, the CDC reported that four cases of late vitamin K deficient bleeding (VKDB) were confirmed in Nashville, Tennessee.  VKDB has been recognized for decades as has its simple prevention – a single injection of Vitamin K post partum. In the case of Nashville, parents refused the preventative Vitamin K injection because they perceived a risk of it causing leukemia. There has been no scientific basis for believing that Vitamin K causes leukemia but nevertheless the parents perceived a risk based on unsubstantiated reports and made a choice that put their newborn in actual risk of dying.
Perceived risk is probably at least a contributing factor to the angst felt by some over GMOs. Despite the preponderance of scientific evidence showing there is no harm from GMOs, the fear felt by some seems to border on hysterical. One wonders what transformation would take place if those fearful of the GMOs understood the science better. Slovic’s work would indicate that their perceived risk would decrease with increased knowledge.
Is it also possible that the Dunning Kruger effect may play a role in intensifying the perception of risk or at least validating the risk as real? The Dunning Kruger effect says that people lacking knowledge of a subject tend to have a higher self-assessment of their knowledge than those people who actually do have greater knowledge . In a sense, they lack sufficient knowledge to know what they don’t know. If Slovic is correct, perceived risk is increased by lack of subject matter knowledge and if Dunning Kruger is operative it would suggest the same lack of subject matter knowledge would lead to a higher confidence that the perceived risk is a valid risk.
Human nature is what it is and short of some great initiative to incorporate critical thinking into our educational curriculum it seems that people will likely continue making their decisions based on perceived risk and not actual risk and will likely be quite confident they are making the right decision.
Exacerbation by echo chambers
It would be difficult to deny that the problems related to decision made by perceived risk have not been exacerbated by the current state of technology. In the age of social media and the ubiquitous internet, cloistered communities of like thinking people can easily aggregate and create a positive feedback loop for their particular belief – or misbelief. Baseless beliefs that would have been modulated by tempered voices a decade ago are now free to feed upon themselves reinforcing the perceived risks as valid.
Complicit in catalyzing the reaction to perceived risk is the national media that focuses on every kidnapping as if it were likely to occur next door. The reality is that it is not. This is not to say that one must not be prudent in their actions but at the same time it is important to approach life with the ability to objectively distinguish real risk from faux risk. Otherwise, one lives in fear of the unlikely and may be blindsided by the likely.