Men are more likely to go missing and die during a night out in December than at any other time of year, a study found.
More than half of 97 fatal disappearances recorded between January 2010 and August this year involving men occurred during winter, with 20% in December alone.
Five had been to a Christmas party and another five went missing on New Year's Eve or in the early hours of January 1, the research noted.
A large number of the deaths involved water, with waterways proving a significant factor in 86 cases.
The study, carried out by London's Kingston University and the UK Missing Persons Bureau, part of the National Crime Agency, has prompted calls for males to look after friends out celebrating over the Christmas party season, particularly when walking near rivers, canals and docks.
Geoff Newiss, an honorary fellow at Kingston University who led the research, said he hoped it would lead to more effective search strategies for missing people.
He said: "It's a tragedy for any family to have a husband, son or brother go missing on a night out and then be found to have died. But it's made a lot worse when families are left wondering what's happened to their loved one for weeks and, in some cases, years.
"One of the key goals of this project is to identify steps to reduce delays in finding missing people who have died which will help give anxious families and friends some closure."