PAWai Evidence Library

Evidence behind the guidance.

Every insight here is traced back to a real, peer-reviewed paper — with its evidence level, study type, and limitations shown plainly. None of it is for diagnosis or treatment decisions; it's here to inform you and your conversations with your veterinarian.

Latest Research

Dog Weight Isn’t Only Calories — Environment and Behaviour Matter Too

A 2026 paper used dogs as a companion-animal model to study how behaviour and environment relate to obesity risk. PAWai helps you track patterns — your vet guides care.

Canine Weight ManagementModerate evidence
Source
BMC Veterinary Research, 2026
Study type
Observational companion-animal study
PAWai use
EducationalTriage Support
⚠ Not for decision-making — for education and visit preparation only

Heartworm Prevention Is Evidence-Heavy — Here’s One 2026 Field Trial, Plainly

A 2026 multicentre field trial studied a novel chewable tablet for preventing heartworm disease in dogs. PAWai translates what the paper covers — without telling you what to give your dog.

Heartworm PreventionModerate evidence
Source
Parasites & Vectors, 2026
Study type
Multicenter field trial
PAWai use
EducationalTriage Support
⚠ Not for decision-making — for education and visit preparation only

Omega-3 and Dog Joints: Separate the Marketing from the Evidence

Omega-3 products are everywhere in joint-care marketing. PAWai’s Knowledge Engine topic on canine osteoarthritis focuses on honest limits: educational context only, then your veterinarian.

Canine Osteoarthritis & NutritionLow evidence
Source
Multiple (Knowledge Engine topic RT-001), 2026
Study type
Evidence snapshot / literature topic
PAWai use
EducationalTriage Support
⚠ Not for decision-making — for education and visit preparation only

Most Anaesthetic Deaths Happened After the Procedure, Not During It

A UK study of over 185,000 anaesthetics found death risk of about 1 in 601 dogs and 1 in 419 cats, falling to 1 in 1,849 and 1 in 895 in healthy animals — with most deaths after the procedure.

Perioperative Anaesthetic RiskModerate evidence
Source
Veterinary Anaesthesia and Analgesia, 2008
Study type
Prospective multicentre cohort study with nested case-control
PAWai use
EducationalPreventive Guidance
⚠ Not for decision-making — for education and visit preparation only

In 15,000 Dogs, the Odds of Cognitive Dysfunction Rose 52% With Each Additional Year of Age

A 2022 study of 15,019 companion dogs found the odds of canine cognitive dysfunction rose 52% with each additional year of age, and were 6.47 times higher in dogs their owners described as not active.

Canine Cognitive DysfunctionModerate evidence
Source
Scientific Reports, 2022
Study type
Cross-sectional analysis within a large prospective cohort (owner-reported rating scale)
PAWai use
EducationalObservation Support
⚠ Not for decision-making — for education and visit preparation only

Insured Dogs Were Diagnosed With Cruciate Rupture Far More Often — Which Says More About Diagnosis Than About Knees

A UK study of 1,000 cruciate rupture cases found higher odds in middle-aged and neutered dogs and in three particular breeds — and in insured dogs, which reveals as much about diagnosis as about disease.

Canine Cruciate Ligament DiseaseModerate evidence
Source
The Veterinary Journal, 2023
Study type
Retrospective cohort study of primary-care clinical records (VetCompass)
PAWai use
EducationalObservation Support
⚠ Not for decision-making — for education and visit preparation only

Cats With Kidney Disease Went Less Often — a Change Only Someone Watching the Litter Box Would See

In a 2021 survey where owners tracked litter box use for a week, 42% of cats with chronic kidney disease passed a stool less than once a day, compared with 15% of apparently healthy cats.

Feline Chronic Kidney DiseaseLow evidence
Source
Journal of Feline Medicine and Surgery, 2021
Study type
Cross-sectional owner-reported survey with a 7-day observation period
PAWai use
EducationalObservation Support
⚠ Not for decision-making — for education and visit preparation only

Overweight Dogs Lived Shorter Lives in All 12 Breeds One Large Study Examined

In a study of 50,787 middle-aged dogs, overweight dogs had a shorter median life span than dogs in normal body condition — in every one of the 12 breeds examined.

Canine Weight & Body ConditionModerate evidence
Source
Journal of Veterinary Internal Medicine, 2019
Study type
Retrospective case-control study
PAWai use
EducationalPreventive Guidance
⚠ Not for decision-making — for education and visit preparation only

One Dog in Fourteen Was Diagnosed With Ear Disease in a Single Year — and Ear Shape Was a Major Reason

A study of 22,333 UK dogs found 7.30% were diagnosed with ear disease in one year, with breed and ear shape the strongest predictors.

Canine Otitis ExternaModerate evidence
Source
Canine Medicine and Genetics, 2021
Study type
Retrospective cohort study of primary-care clinical records (VetCompass)
PAWai use
EducationalPreventive Guidance
⚠ Not for decision-making — for education and visit preparation only

Almost Every Owner Reported a Problem Behaviour — and Four in Five Had Used Aversive Training

In 985 dogs followed to 21 months, 96.7% of owners reported at least one problem behaviour and 82.3% had used aversive training methods — with online puppy classes the sole protective factor identified.

Canine Behavioural DevelopmentLow evidence
Source
Animals, 2024
Study type
Longitudinal online owner-reported cohort study
PAWai use
Educational
⚠ Not for decision-making — for education and visit preparation only

Healthy Dogs on Grain-Free Diets Showed No Heart Changes on Ultrasound — but a Marker of Muscle Injury Was Higher

In 188 healthy dogs, grain-free and grain-inclusive diets produced no differences on ultrasound or in taurine — but a marker of heart-muscle injury was higher in the grain-free group.

Diet-Associated Canine Heart DiseaseLow evidence
Source
Journal of Veterinary Internal Medicine, 2021
Study type
Observational cross-sectional study
PAWai use
Educational
⚠ Not for decision-making — for education and visit preparation only

Exertion Caused Far More Heatstroke in UK Dogs Than Hot Cars Did

In a 2020 study of 905,543 UK dogs, exercise triggered 74.2% of heat-related illness events, while confinement in a hot vehicle accounted for 5.2%.

Canine Heat-Related IllnessModerate evidence
Source
Animals, 2020
Study type
Retrospective cohort study of primary-care clinical records (VetCompass)
PAWai use
EducationalPreventive Guidance
⚠ Not for decision-making — for education and visit preparation only

Six in Ten Owners Did Not Recognise Breathing Trouble in Dogs a Test Showed Had It

In a 2015 study of 89 French Bulldogs assessed with objective airway testing, 60% of owners failed to recognise brachycephalic obstructive airway syndrome in dogs the grading identified as affected.

Brachycephalic Airway HealthModerate evidence
Source
PLOS ONE, 2015
Study type
Prospective diagnostic accuracy and instrument development study
PAWai use
EducationalObservation Support
⚠ Not for decision-making — for education and visit preparation only

Cat Owners Scored Feline Pain About as Consistently as Veterinarians Did

A 2023 study of 1,262 cat caregivers across 66 countries found their total pain scores on a facial-expression scale were not significantly different from those given by veterinarians.

Feline Pain RecognitionModerate evidence
Source
Journal of Feline Medicine and Surgery, 2023
Study type
Cross-sectional online survey (image-based reliability study)
PAWai use
EducationalObservation Support
⚠ Not for decision-making — for education and visit preparation only

When Cat Owners Said Their Cat Was Moving Differently, the Examination Backed Them Up

In a 2023 blinded study of 57 cats, those whose owners had noticed early mobility changes had significantly higher pain and joint scores on examination — and 14 times the odds of bilateral disease.

Feline Degenerative Joint DiseaseModerate evidence
Source
Journal of Feline Medicine and Surgery, 2023
Study type
Blinded nested case-control study
PAWai use
EducationalObservation Support
⚠ Not for decision-making — for education and visit preparation only

Owners Rated Their Dog's Itch More Consistently When Shown Their Own Previous Score

In a 2019 study of pruritic dogs, showing owners their previous itch score before they rescored raised agreement with their own perception of change from 79% to 96%.

Canine Pruritus AssessmentModerate evidence
Source
Veterinary Dermatology, 2019
Study type
Prospective randomised comparison of scale administration methods, with a retrospective record analysis
PAWai use
EducationalObservation Support
⚠ Not for decision-making — for education and visit preparation only

Vets Diagnosed Gum Disease in One Dog in Eight. Studies That Look Under Anaesthetic Find Far More.

A 2021 study of 22,333 UK dogs recorded periodontal disease in 12.52% over one year — while examinations of anaesthetised dogs report 44% to 100%, showing how much goes undiagnosed.

Canine Periodontal DiseaseModerate evidence
Source
Journal of Small Animal Practice, 2021
Study type
Retrospective cohort study of primary-care clinical records (VetCompass)
PAWai use
EducationalPreventive Guidance
⚠ Not for decision-making — for education and visit preparation only

Cats With Silent Heart Disease Faced Real Risk — and Almost Nothing an Owner Could See

In the REVEAL study of 1,730 cats, 30.5% of those with preclinical hypertrophic cardiomyopathy developed heart failure or a clot — a disease that produces almost no signs an owner can observe.

Feline Hypertrophic CardiomyopathyModerate evidence
Source
Journal of Veterinary Internal Medicine, 2018
Study type
Retrospective multicentre longitudinal cohort study
PAWai use
EducationalPreventive Guidance
⚠ Not for decision-making — for education and visit preparation only

More Than Half of Cats With Urinary Trouble Had It Again — and the Cause Was Not Always the Same

In a 2019 study of 101 cats with lower urinary tract disease, 58.1% of those with a known diagnosis had a recurrence — and 14 cats had a different underlying cause at a later episode.

Feline Lower Urinary Tract DiseaseLow evidence
Source
Journal of Feline Medicine and Surgery, 2019
Study type
Retrospective owner-interview follow-up study
PAWai use
EducationalObservation Support
⚠ Not for decision-making — for education and visit preparation only

Nearly Three in Ten Treated Diabetic Cats Reached Remission — and Remission Meant a Better Life

In a 2023 study of 477 cats with diabetes, 29% of treated cats achieved remission, and remission was associated with a better quality of life for the cat.

Feline Diabetes MellitusLow evidence
Source
Journal of Veterinary Internal Medicine, 2023
Study type
Retrospective cross-sectional owner questionnaire study
PAWai use
Educational
⚠ Not for decision-making — for education and visit preparation only

Most Cats With Hyperthyroidism Lost Weight While Still Looking a Normal Size

In 462 untreated hyperthyroid cats, median weight had fallen from 5.45 kg one to two years earlier to 4.36 kg at diagnosis — yet only about a third looked underweight, while 77% had lost muscle mass.

Feline HyperthyroidismModerate evidence
Source
Journal of Veterinary Internal Medicine, 2016
Study type
Prospective cross-sectional and before-after study
PAWai use
EducationalObservation Support
⚠ Not for decision-making — for education and visit preparation only

Owners Had a Rough Idea What Their Dogs Did Home Alone — and Were Best on the Damage They Could See

Compared with video of what dogs actually did after their owners left, owner questionnaire scores correlated only moderately — and best for the behaviours that leave visible traces.

Canine Separation-Related BehaviourLow evidence
Source
Journal of Veterinary Behavior, 2018
Study type
Prospective validation study comparing owner questionnaire responses with video recordings
PAWai use
EducationalObservation Support
⚠ Not for decision-making — for education and visit preparation only

Pain and Suffering Was the Most Common Reason Owners Gave for Euthanasia

Among 646 bereaved dog owners, 83% of dogs were euthanased — most often because of pain or suffering (48.5%), then poor quality of life (24.8%).

Canine End-of-Life CareModerate evidence
Source
Journal of the American Veterinary Medical Association, 2026
Study type
Cross-sectional owner survey using a validated instrument
PAWai use
Educational
⚠ Not for decision-making — for education and visit preparation only

Your Dog Doesn't Have to Be Old to Show Signs of Osteoarthritis

In one 2024 study of 123 young dogs, researchers found radiographic signs of osteoarthritis in nearly 40% of dogs screened — and most owners didn't notice.

Early Canine OsteoarthritisModerate evidence
Source
Scientific Reports, 2024
Study type
Prospective cross-sectional study
PAWai use
EducationalTriage Support
⚠ Not for decision-making — for education and visit preparation only