Paraskevidekatriaphobia is a phobia of Friday the 13th. Yes, they actually gave it a name. On a cerebral level, we all know that Friday the 13 is no more unlucky than any other day of the year. And yet the cloud over the day persists. What’s going on?

It's not unusual for people to believe in myths. For instance, some people still think Brexit was a good idea. Even though science has come a long way, horoscopes are still very popular. Other things that people like are alternative medicine and secret theories. As Carl Sagan noted in his 1980’s TV series ‘Cosmos,’ almost every newspaper contains a daily horoscope but you would be hard pressed to find a regular science piece. With so many far-fetched notions celebrated in popular culture, the observance of one particular day as being non-specifically ‘unlucky’ seems positively uncontroversial.

Where did the fear of Friday the 13th come from? It's hard to pinpoint where it came from and how it changed over time. Theories centre on events that happened at the Last Supper. The prophet Judas, who was the thirteenth guest, is said to have betrayed Jesus. Who knows, but beliefs will always be stronger if they are talked about. In the early 1800s, Thomas Lawson wrote a book about how a stockbroker used people's myths about the day to make money. The main character of the book, the "hero," wants to use fear to make the Wall Street markets go crazy. As if life were a work of art, the book has since led to several studies of how the stock market acts on Fridays that happen on the 13th of the month. A close study of the data doesn't show any change. When all of the stories were looked at together, most of them agreed that market returns on Friday the 13th are usually (slightly) better than on other Fridays.

Why should Friday the 13th be an anomaly? The calendar we use to mark the passage of time is a human construct. Perhaps the perceived connection between Friday the 13th and bad luck is numerical in nature (triskaidekaphobia – extreme superstition regarding the number 13), deriving from our feelings of there being something inherently unnatural about the number 13? There are a host of numbers, an uncountable amount (ironically), so why should a single one be unlucky? People's thoughts about numbers are based on a surprising amount of psychology. But since numbers have been around for a long time, maybe we shouldn't be shocked. Some say that "even" numbers are easier to change (by dividing or multiplying) than "odd" ones. This means that "odd" numbers take more mental effort, which is why they "resonate" more with our minds. It could be a good or bad thing, but it does mean that it takes more biological effort, which could be discouraging. Ask anyone who has ever had to force themselves to go to the gym. There's a chance that it has something to do with how people feel about #13. For example, there are 12 months in a year, 12 hours in a day, 12 days of Christmas, and 12 inches in a foot. We learn our multiplication tables in school, but most of the time we only learn up to the 12 times table.

Clearly, there's no good reason to be afraid of the chance of bad luck happening on a certain day, date, or number. In some countries, certain numbers are seen as bad luck. In Italy, the number 17 is thought to be less lucky than the number 13, and in China, it's the number 4. For some mental noise, you might be interested to know that the Roman numeral XVII can be rearranged to make "VIXI," which comes from the Latin phrase "my life is over." What more proof do you need that 17 is not a good number? This may be one reason why Friday the 13th stories keep coming up: cherry-picking. People who are sure of what they believe can easily find evidence to back it up, as long as they don't look at anything that goes against what they believe.

The Oedipal overtones associated with Friday the 13th are amusing – that is, a person often meets their destiny on the road they take to avoid it. It has been estimated that business in the US loses $800 or $900 million [US] on Friday the 13th, mainly because people will not fly or do business they normally would do. Ironically, people heeding their superstitious fears end up staying at home –where statistically more accidents happen – passing up a chance to spend the day in a slightly less dangerous workplace. A 2008 study by the Dutch Centre for Insurance Statistics revealed that fewer traffic accidents occur on Friday the 13^th than on other Fridays. Reports of fire and theft also drop.

There isn't much scientific proof that bad experiences or accidents are more likely to happen today than on other days. Scientists have still looked for them, though. Most studies that have looked at traffic accidents haven't found any patterns that would suggest Friday the 13th is a more dangerous day to drive than other Fridays. One study did find, though, that the chance of going to the hospital because of a car accident was up to 55% higher on Friday the 13th than on other Fridays [1]. The authors of that study suggested staying home that day. It was in the Christmas issue of the BMJ, though, which is a jokey version of a medical journal that is known to sometimes print serious research. Superstitious patients often express significant concern and anxiety when undergoing a surgical procedure on Friday the 13th. In one retrospective cohort, researchers found no evidence to suggest that patients undergoing surgery then were more likely to experience death, or short- and long-term complications [2].

People are careful around Friday the 13th because their society has taught them that the day is linked to bad things. That's why superstitions are specific to certain countries and come in a lot of different forms. However, safety is the main reason. As you might expect (I hope), safety is the most important thing in the pharmaceutical business, and most people agree that if you don't plan, you plan to fail. In the same way, small businesses shouldn't rely on luck, good or bad; they should be ready for any emergency. Trust comes from figuring out how dangerous something is.

Most businesses have standard operating procedures (SOPs) but does your SOP system include a disaster recovery plan (DRP)? It should. The Quality Team at Niche report that this is the SOP that most often ‘missing’ when we perform reviews, audits and vendor assessments. (The other is an SOP on writing SOPs – if you are missing this one we provide a free template here). It makes you wonder how company directors expect to maintain business continity.

The DRP usually takes the form of a documented process or set of procedures to recover and protect your business’ infrastructure in the event of a disaster. Such a plan specifies the procedures an organization must follow. The disaster could be natural, supernatural or man-made. Manmade disasters might be intentional (for example a break-in) or unintentional (such as commuter disruption following a major derailment). Given our increasing dependency on information technology DRPs often focus on the recovery of information technology data, communication resources, assets, and facilities required to maintain your normal working. Every good IT engineer knows that printers are possessed by evil spirits and plan accordingly. A good DRP usually addresses three basic questions: objective and purpose, roles and responsibilities and actions to follow when the disaster strikes. I speak from experience when I say it’s especially important for small businesses that you are not the only person who knows what’s going on (or what should be going on) when the biowaste comes into contact with the rotating blade assembly. Bad luck isn’t just a flood or a tsunami – it could be a medical emergency that places you out of commission for several months. Don’t leave it too late to train up someone to manage your business.

Today of all days, planning for the worst and hoping for the best will make you feel safer. It allows me to believe, albeit it briefly, that I have some level of control over my circumstances.

References

1. Scanlon TJ, et al. Is Friday the 13th bad for your health? BMJ. 1993 Dec 18-25;307(6919):1584-6. 
2. Ranganathan S, et al. Superstition in Surgery: A Population-Based Cohort Study to Assess the Association Between Surgery on Friday the 13th and Postoperative Outcomes. Ann Surg Open. 2024 Feb 12;5(1):e375.