Objective—To assess validity and reliability for a visual analogue scale (VAS) used by owners to measure chronic pain in their osteoarthritic dogs.
Sample—68, 61, and 34 owners who completed a questionnaire.
Procedures—Owners answered questionnaires at 5 time points. Criterion validity of the VAS was evaluated for all dogs in the intended-to-treat population by correlating scores for the VAS with scores for the validated Helsinki Chronic Pain Index (HCPI) and a relative quality-of-life scale. Intraclass correlation was used to assess repeatability of the pain VAS at 2 baseline evaluations. To determine sensitivity to change and face validity of the VAS, 2 blinded, randomized control groups (17 dogs receiving carprofen and 17 receiving a placebo) were analyzed over time.
Results—Significant correlations existed between the VAS score and the quality-of-life scale and HCPI scores. Intraclass coefficient (r = 0.72; 95% confidence interval, 0.57 to 0.82) for the VAS indicated good repeatability. In the carprofen and placebo groups, there was poor correlation between the 2 pain evaluation methods (VAS and HCPI items) at the baseline evaluation, but the correlation improved in the carprofen group over time. No correlation was detected for the placebo group over time.
Conclusions and Clinical Relevance—Although valid and reliable, the pain VAS was a poor tool for untrained owners because of poor face validity (ie, owners could not recognize their dogs' behavior as signs of pain). Only after owners had seen pain diminish and then return (after starting and discontinuing NSAID use) did the VAS have face validity.
Objective—To determine the validity, reliability, and sensitivity of a published chronic pain index by completion of a questionnaire in Finnish by owners of dogs with chronic signs of pain caused by osteoarthritis.
Animals—61 client-owned dogs with osteoarthritis.
Procedures—Validity, internal consistency, and repeatability testing of the questionnaire were evaluated by completion of questions in Finnish by owners of 61 dogs; the questionnaire was named the Helsinki chronic pain index (HCPI). Sensitivity testing of the questionnaire was determined from data of 2 smaller groups of dogs treated with carprofen (n = 17) or placebo (17). Owners completed the questionnaire 5 times during a 16-week period. Psychometric properties of the HCPI were evaluated.
Results—Principal component analysis yielded only a single stable component, indicating that the HCPI was best explained as an 11-item single construct index of chronic pain. Changes in the HCPI correlated well with change in quality of life and with change in the mobility visual analogue scale (r = 0.72 and r = 0.67, respectively), indicating a high predictive validity. Internal consistency (Cronbach A value = 0.82) and test-retest reliability (intraclass correlation coefficient = 0.84 for items and 0.92 for the HCPI) were high. Changes in scores (from baseline to treatment and back to no treatment) between the carprofen treatment group and placebo control group were significant, indicating high sensitivity.
Conclusions and Clinical Relevance—The Finnish version of the HCPI provided a valid, reliable, and responsive tool for assessment of response to treatment in dogs with osteoarthritis.
Objective—To evaluate, by means of an owner questionnaire, long-term outcome and prevalence of chronic pain after cranial cruciate ligament (CCL) surgery in dogs.
Design—Retrospective case series.
Animals—253 dogs with surgically treated CCL rupture.
Procedures—Data from surgical records of dogs that underwent surgical repair of CCL between 2004 and 2006 were reviewed. An owner questionnaire, including the validated Helsinki chronic pain index (HCPI), served to evaluate long-term outcome and prevalence of chronic pain after surgical repair by means of intracapsular, extracapsular, or osteotomy techniques. Additional questions inquired about recovery and rehabilitation after surgery, current well-being, medications, and adjunct treatments.
Results—Of 507 questionnaires, 272 (53.6%) were returned; 19 were excluded because of incomplete answers. Mean ± SD follow-up time was 2.7 ± 0.8 years (range, 1.3 to 4.5 years). Owners considered surgical outcome as excellent in 122 of 226 (54.0%) dogs, good in 97 (42.9%), fair in 0 (0%), and poor in 7 (3.1%). At follow-up, the mean ± SD HCPI for 206 dogs was 8.9 ± 6.3 (range, 0 to 24). Of these 206 dogs, 64 (31.1%) had an HCPI ≥ 12, indicating chronic pain. Mean HCPI in dogs with a good outcome (11.8 ± 5.4; 95% confidence interval, 10.6 to 12.9) was significantly higher than that for dogs with an excellent outcome (6.2 ± 5.7; 95% confidence interval, 5.1 to 7.2). Owner-reported postoperative lameness was significantly shorter after osteotomy techniques, compared with lameness duration after the intracapsular technique.
Conclusions and Clinical Relevance—On the basis of owner assessment, long-term chronic pain was found in approximately 30% of dogs after CCL repair.
Animals—22 dogs with osteoarthritis in the hip or elbow joint.
Procedure—13 dogs received orally administered carprofen daily for 2 months, and 9 dogs received a placebo for 2 months. Dogs were weighed, and serum and urine samples were collected before initiation of treatment and 4 and 8 weeks after initiation of treatment. Serum concentrations of total protein, albumin, urea, and creatinine and serum activities of alkaline phosphatase (ALP) and alanine aminotransferase (ALT) were measured. Urinary ALP-to-creatinine, γ-glutamyltransferase (GGT)-to-creatinine, and protein-to-creatinine ratios were calculated. Dogs were observed by owners for adverse effects.
Results—Serum protein and albumin concentrations were lower in treated dogs than in those that received placebo at 4 weeks, but not at 8 weeks. No changes were observed in serum urea or creatinine concentrations; ALP or ALT activity; or urinary ALP-to-creatinine, GGT-to-creatinine, or protein-to-creatinine ratios. Dogs' weights did not change. Severity of vomiting, diarrhea, and skin reactions did not differ between groups, but appetite was better in dogs receiving carprofen than in dogs in the placebo group.
Conclusions and Clinical Relevance—It is possible that the transient decreases in serum protein and albumin concentrations in dogs that received carprofen were caused by altered mucosal permeability of the gastrointestinal tract because no indications of renal or hepatic toxicity were observed. Carprofen appeared to be well tolerated by dogs after 2 months of administration.
Objective—To identify variables and evaluate methods
for assessing chronic pain in dogs.
Animals—41 dogs with canine hip dysplasia (CHD),
and 24 apparently healthy dogs with no history of
Procedure—2 veterinarians evaluated the dogs' locomotion
and signs of pain. Owners of dogs with CHD
and control dogs answered a questionnaire regarding
their dogs' demeanor, behavior, and locomotion
(descriptive scales) and assessed pain and locomotion
(visual analog scales). Plasma concentrations of
several stress-related hormones were determined,
and 13 radiologic variables were assessed in affected
Results—For many of the questions, answers provided
by owners of dogs with CHD differed significantly
from those of owners of control dogs. Stress hormone
concentrations differed significantly between
dogs with CHD and controls, but individual variation
was too great for them to be of value in pain assessment.
None of the radiologic variables examined correlated
well with owner or veterinarian pain scores.
Conclusions and Clinical Relevance—Chronic pain
could be assessed in dogs with CHD through completion
of the study questionnaire by a person familiar
with the pet (eg, owner) after receiving appropriate
education in its use. Eleven variables were identified
as being potentially useful in assessment of chronic
pain in dogs. (J Am Vet Med Assoc 2003;222: