According to a survey by the American Pet Products Association, nearly half of all dogs sleep on their owners’ beds.

And according to a recent study at the Mayo Clinic in Arizona, people who sleep with their dog on the bed sacrifice sleep.

But maybe not enough to matter: “Most people assume having pets in the bedroom is a disruption,” says Lois Krahn, M.D., the corresponding author of the study. “We found that many people actually find comfort and a sense of security from sleeping with their pets.”

It’s a question of sleep efficiency.

That’s the percentage of time a person spends actually asleep while in bed. It’s calculated by dividing the amount of time spent asleep (in minutes) by the total amount of time spend in bed (also measured in minutes).

For example, let’s say you go to bed at 11 p.m. It takes you 25 minutes to fall asleep, and you wake up twice during the night for five minutes each time. You wake for the day at 6 a.m.

Your total time in bed equals seven hours (420 minutes). Subtract how long it took to fall asleep (25 minutes), and the times you woke up (10 minutes total), for a total sleep time of 385 minutes. Now divide 385 minutes by 420 minutes to get your sleep efficiency, which is 92%.

In sleep science, anything above 85% is considered a healthy sleep efficiency. Your 92% is considered very good.

For the study, researchers evaluated the sleep efficiency of 40 healthy adults for five months. The average age of the study participants was 44, and 88% were women. None of the subjects had sleeping disorders.

The dogs were of various breeds, and all were over six months of age.

Both sets of participants, humans and dogs, wore activity trackers to monitor their sleep activity. The dogs wore FitBarks, an activity tracker that attaches to the collar and records the dog’s activity whether it’s active or at rest. The people wore activity monitors that recorded their movements whether they were soundly asleep or not. Both monitors were set to monitor movement every minute.

The humans also kept sleep diaries.

The researchers found that when a dog was on the bed, both owner and dog slept reasonably well, with the dogs getting the slightly better deal: Owners had an average sleep efficiency of 81%, while the dogs averaged 85%.

However, the owners slept slightly better when the dogs were in the room, but not on the bed.

Those owners averaged 83% sleep efficiency. The dogs slept the same whether they were on the bed or somewhere else in the room.

So, if you’ve been sleeping poorly and you really need need that extra 2% sleep efficiency, don’t feel guilty about booting your dog off the bed.

Odds are he won’t lose any sleep over it.

Photo credit: © iStock/damedeeso