A large, ongoing international study from the University of Exeter, dubbed the "Santa survey," is investigating how, and at what age, children begin to change their minds about the existence of Santa Claus. The research also examines whether a child's trust in adults is threatened by the discovery that Santa isn't real.

So far, the Exeter Santa Survey has collected more than 1,200 responses, and psychologist Chris Boyle is keen to get more data before officially publishing the results next year. The study examines how beliefs around Santa Claus vary across the world, but there is a particular focus on understanding what kind of impact it has on children when they learn this jolly gift-giving icon does not exist.

The early results in the survey reveal the average age children stop believing in Santa Claus is eight. This conclusion does follow on from prior research that found that between eight and nine was the average age most adults tend to remember stopping believing in Santa.

Interestingly enough, when researchers directly interview children they tend to discover belief in Santa drops off at a much younger age. Jacqueline Wooley, a psychologist from the University of Texas, found when talking to children directly, belief peaks at around five years of age and tapers off significantly by the age of eight or nine.

So it seems that adults often prefer to think children believe in the existence of Santa Claus much longer than the kids actually do. This conclusion does sync up with a finding from the new Exeter Santa Survey suggesting 65 percent of respondents, "played along with the Santa myth, as children, even though they knew it wasn't true."

More interesting than what age the disbelief arose were the findings on the why and how children started to question their reality. "It has been fascinating to hear why they started to believe he is fictional," says Boyle. "The main cause is either the accidental or deliberate actions of parents, but some children started to piece together the truth themselves as they became older."

The initial findings from the survey revealed many children first began to suspect Santa wasn't real when their parents made fundamental errors in hiding the truth from presents discovered hidden before Christmas, to one child finding price tags from the local shop on presents allegedly from the North Pole. From the age of seven or eight it also seems as though an increasing awareness of the world slowly dismantled the illusion. By age nine, one respondent had "Learnt enough about math, physics, travel, the number of children on the planet ratio to the size of the sleigh to figure it out on my own".

For years debate has raged over whether parents should lie to their children about the existence of Santa Claus. Some suggest that the years of deliberate obfuscation degrades a sense of trust children have in their parents, and the results of this new survey do back up that conclusion. A third of the respondents confirmed they were upset upon discovering Santa wasn't real and it had negatively affected their trust in adults.

Of course not everyone scrooged on the mystery of Santa Claus, in fact the survey found over 70 percent of respondents are happy to continue the ruse with their children. Even noted atheist Richard Dawkins sees value in raising children to believe in the myth of Santa. Dawkins, while adamantly against indoctrinating children into supernatural beliefs, suggests the inevitability of a child learning Santa doesn't exist can result in an important early lesson in skepticism.

"Santa Claus again could be a very valuable lesson because the child will learn that there are some things you are told that are not true," Dawkins said to The Guardian in 2014. "Now isn't that a valuable lesson? Unfortunately it doesn't seem to have had the desired effect in some cases, because after children learn that there is no Santa Claus, mysteriously they go on believing that there is a God."

The Exeter Santa Survey is ongoing and open for new respondents.