A new Virginia Tech study published in PLOS One establishes a crucial baseline for understanding dog behavior on a large scale.
The research, led by Courtney Sexton, a postdoctoral associate in the Virginia-Maryland College of Veterinary Medicine, and her colleague Yuhuan Li from the University of Washington, utilized four years of owner-reported data from over 47,000 dogs in the Dog Aging Project, a large-scale initiative involving over 40 institutions.
"Most importantly, with these data, we're excited to now have a starting point from which we can continue to follow changes in the behaviors of tens of thousands of dogs as they age, which will ultimately help us understand how behavior and health are linked," Sexton said.
This study's power lies in its sheer size.
Sexton said, "When you have a data set this big, you really do have power in numbers. While we can't understand all the factors, when we find statistical significance, there is likely something there worth thinking about in its real-world context."
The original motivation: Find out how the COVID-19 pandemic affected the well-being of our canine companions. The researchers analyzed four years of owner-reported data from 2020-23, specifically examining trends in fear, attention/excitability, aggression, and trainability.
It turns out, dogs are adaptable.
"We saw that certain factors, such as a dog's life stage, sex, and size had some influence on their behavior," said Sexton. "Interestingly, we found that throughout the COVID-19 pandemic time period, there were not substantial changes in dogs' overall behavioral profiles from year to year despite what we might have expected given the changes in environment and routines that many were experiencing at that time."
The study did, however, reveal one small but notable exception: trainability. Dogs enrolled in the study after 2020 had lower average trainability scores. This was in contrast to dogs already enrolled in 2020 as adults that likely benefited from pre-pandemic training experience.
While the data doesn't offer a definitive cause, researchers speculate that the pandemic's unique circumstances — such as more dogs being adopted from shelters or owners being more stressed and less able to dedicate time to training — could be contributing factors.
“What was interesting was that the difference in reported trainability between the first year and the last year was the smallest of any in the averages,” said Sexton. “It’s a small statistical significance but could show that dogs, or their owners, are bouncing back.”
Future work will explore how factors such as a dog's location or their health status might influence behavior over time. The goal is to better prepare dogs and their owners for whatever life throws at them, whether it's a pandemic or just the challenges of everyday life.
PLOS One
An analysis of behavioral characteristics and enrollment year variability in 47,444 dogs entering the Dog Aging Project from 2020 to 2023
10-Sep-2025