U.S. — In surprising results following years of extensive research, a new study confirmed that an astonishing 9 out of 10 serial killers were made to wear matching pajamas for childhood family photos.

The study, which compiled several decades of data stretching back to the early 1900s, found that an overwhelming majority of sociopaths, psychopaths, and objectively evil murderers all shared the common formative experience of being forced to wear matching jammies during family photo shoots.

"We're starting to consider the possibility that there's a correlation," said lead researcher Dr. Blake Rumsey of the Center for Analyzing Data for Analysis. "We studied serial killers from the last century and interviewed other murderers currently incarcerated and found that nearly all of them were subjected to family photo shoots in matching sets of pajamas when they were children. It was surprising and bone-chilling at the same time."

The research team recounted harrowing tales told to them by imprisoned serial killers. "Some of the stories were really difficult to listen to," said research assistant Tiana Martin. "Dinosaur pajamas… matching puppy and kitten slippers… and the Christmas pajamas, dear God in Heaven, the Christmas pajamas. It's no wonder these poor souls grew up to become sadistic, bloodthirsty killers. They never had a chance to be anything else."

At publishing time, researchers were planning a follow-up study to determine the veracity of claims that a majority of violent criminals had been forced to wear sweaters their grandparents had given them for Christmas the next time they visited Grandma and Granpa's house.

BIG NEWS: We made a movie, and you can watch the trailer NOW: