Plain-English summary
Almost everyone who lives with a dog will one day face the hardest decision in pet ownership, usually with very little idea of what other people's experience of it has been.
The Dog Aging Project surveyed 646 bereaved owners about how their dogs died. The results are not comfortable reading, but they are useful: they describe what actually happens, at what age, and what owners say drove their decisions.
Most dogs — 83% — were euthanased rather than dying unassisted. The reason owners gave most often was not a diagnosis. It was pain and suffering.
What the study found
Owners whose dogs died between December 2019 and March 2021 were invited to complete the End of Life Survey. Of 793 invited, 655 responded — a response rate of 85.7%, which is unusually high for a survey of this kind. After exclusions, 646 responses were analysed.
Mean age at death was 13.0 years (SD 3.0).
Most dogs, 536 of 646 (83.0%), experienced euthanasia rather than unassisted death. Of those euthanasias, 411 (76.7%) took place in a veterinary clinic and 122 (22.8%) in the owner's home. Ninety-five of the 646 dogs (14.7%) died without any veterinary involvement at all.
The most common owner-perceived causes of death were cancer, in 192 of 646 (29.7%); "old age", in 190 (29.4%); and organ system diseases, in 144 (22.3%).
The most common reason given for euthanasia was pain and/or suffering, in 260 of 536 (48.5%), followed by poor quality of life in 133 (24.8%).
Perimortem quality of life was negatively associated with age at death — the older the dog, the poorer the owner-rated quality of life near the end.
The authors' framing is aimed at the profession: owners' perceptions about pain, suffering, quality of life and old age influence euthanasia decisions, and understanding those perceptions helps veterinarians support families better.
What this study cannot tell you
Every substantive variable here is owner-perceived. "Cause of death" is what the owner believed, not what a post-mortem established, and 29.4% of dogs were recorded as dying of "old age" — which is a way of describing an ending, not a mechanism.
The instrument's own validation is the sharpest caveat, and it deserves stating rather than burying. Agreement was substantial for cause of death (κ = 0.73, 95% CI 0.5 to 0.95), but only moderate for perimortem quality of life (κ = 0.49, 95% CI 0.26 to 0.73) and fair for reason for euthanasia (κ = 0.3, 95% CI 0.08 to 0.52). That last confidence interval comes close to zero. The headline figure — 48.5% for pain and suffering — rests on the least reliable item in the survey.
The Dog Aging Project is a volunteer cohort of engaged owners, and these particular respondents chose to complete a survey about their dog's death. Owners who found the loss too painful to revisit are absent by construction, and it is not knowable which way that shifts the results.
The mean age at death of 13.0 years pools all body sizes. Canine life expectancy varies substantially with size, so this figure describes the cohort rather than any dog.
Finally, this study is descriptive. It does not evaluate whether any approach to end-of-life care produces better outcomes for dogs or for the people who love them.
What pet owners should track
Nothing in this study tells you when. What it does show is that the decision is usually made on an assessment of pain and daily experience — and those are exactly the things that change too slowly to notice without a record.
- Mobility: getting up, stairs, slipping, whether your dog still chooses to move
- Appetite and drinking, and whether encouragement is now needed
- Toileting, including accidents in a previously clean dog
- Sleep, restlessness, and pacing at night
- Interaction: whether your dog still seeks you out, and still does the things it has always enjoyed
- Good days and bad days, counted — the ratio over weeks tells you more than any single day
- Every medication, its dose and whether it still seems to help
If you use a quality-of-life scale, use the one your veterinarian gives you and record the score with its date, so you are comparing like with like over time.
None of this is a formula, and no record decides anything. It exists so that the conversation with your veterinarian starts from what has actually been happening rather than from the last few difficult days, which are the ones memory keeps.
What PAWai can help organize
The value of a record here is that decline is gradual and memory is not. A dated account of the last six months lets you and your vet see a trajectory instead of a snapshot. PAWai does not assess quality of life, does not score suffering, and has no part in decisions about euthanasia or end-of-life care. Those belong to you and your veterinarian, together, and no application should position itself anywhere near them. What PAWai contributes is that when that conversation comes, you are not trying to reconstruct a year from memory while distressed.
If you are facing this, your veterinary team can help — including with the question of timing. Asking early is not premature.
Disclaimer
PAWai organizes information and educates pet owners. PAWai does not diagnose conditions or recommend treatment. Always consult a licensed veterinarian for medical decisions about your pet.
Citation
McNulty, K. E., Ruple, A., Fitzpatrick, A., Wilkins, V., et al. (2026). The Dog Aging Project End of Life Survey reveals owners' perceptions of canine death and highlights areas to improve client education. Journal of the American Veterinary Medical Association, 264, 892–901. https://doi.org/10.2460/javma.25.12.0863
McNulty, K. E., Creevy, K. E., Fitzpatrick, A., Wilkins, V., Barnett, B. G., et al. (2023). Development and validation of a novel instrument to capture companion dog mortality data: the Dog Aging Project End of Life Survey. Journal of the American Veterinary Medical Association, 261, 1326–1336. https://doi.org/10.2460/javma.23.02.0078