The fear of the number 13 has been given a scientific name: "triskaidekaphobia"; and on analogy to this the fear of Friday the 13th is called paraskevidekatriaphobia, from the Greek words Paraskeví (Παρασκευή, meaning "Friday"), and dekatreís (δεκατρείς, meaning "thirteen"). https://en.wikipedia.org/wiki/Friday_the_13th
Scanlon TJ, Luben RN, Scanlon FL, Singleton N. Is Friday the 13th bad for your health? BMJ. 1993 Dec 18-25;307(6919):1584-6.
To examine the relation between health, behaviour, and superstition surrounding Friday13th in the United Kingdom.
Retrospective study of paired data comparing driving and shopping patterns and accidents.
Drivers, shoppers, and residents.
South West Thames region.
MAIN OUTCOME MEASURES:
Numbers of vehicles on motorways; numbers of shoppers in supermarkets; and hospital admissions due to accidents.
There were consistently and significantly fewer vehicles on the southern section of the M25 on Friday the 13th compared with Friday the 6th. The numbers of shoppers were not significantly different on the two
Friday13th is unlucky for some. The risk of hospital admission as a result of a transport accident may be increased by as much as 52%. Staying at home is recommended. Cortesy of Atul Gawande, Complications