Objective—To validate the use of a novel questionnaire as an instrument for measurement of chronic pain in dogs through its impact on health-related quality of life (HRQL).
Animals—108 dogs with chronic degenerative joint disease and 26 healthy dogs.
Procedures—Questionnaire responses were subjected to factor analysis (FA) and questionnaire scores to discriminant analysis to evaluate construct validity. Questionnaire scores were used to explore the potential of this instrument for minimizing respondent bias and for evaluative purposes.
Results—FA results revealed a sensible factor structure accounting for 65% of the variance in data, with factors identifiable as domains of HRQL in dogs affected by chronic pain. Further evidence for construct validity was provided when questionnaire scores were used to discriminate, on the basis of 218 questionnaires, between dogs with clinician-awarded pain scores of 0 and dogs with pain scores ≥ 1 (88% discrimination, with 95% of no-pain group dogs and 87% of some-pain group dogs correctly categorized). Use of the questionnaire provided minimized respondent bias.
Conclusions and Clinical Relevance—Validation of the questionnaire as an instrument for discriminative and evaluative measurements of orthopedic chronic pain through its impact on HRQL in dogs was provided. Use of the questionnaire, with further testing and refinement, may support improved clinical decision making, facilitate development of evidence-based therapeutic options for chronic diseases, and help veterinarians and owners define humane end points in dogs.
Impact for Human Medicine—Information gained here may provide improved measurements of clinical change in animal studies that use dogs with naturally occurring chronic pain to evaluate novel human treatment protocols.
Objective—To develop a reliable, validated questionnaire
that can be used for the assessment of chronic
pain and its impact on health-related quality of life
(HRQL) in dogs.
Sample Population—17 owners of dogs that had
chronic pain associated with chronic degenerative
joint disease and 165 other dog owners.
Procedures—Psychometric methods were used to
identify relevant domains, create an item pool, select
and validate items, and construct and preliminarily
test a structured questionnaire. Relevant domains
were identified through semi structured interviews.
Descriptor-generating exercises provided the terms
owners used to describe these domains and formed
an item pool. A selection from this pool was validated
and used to construct a questionnaire that underwent
Results—The structured questionnaire contained 109
simple, familiar, descriptive terms associated with
good health or chronic pain (most describing subtle
aspects of behavior that owners interpreted as
expressions of subjective experiences of their dogs)
for 13 possible HRQL domains. Each descriptor was
associated with a 7-point numeric scale.
Conclusions and Clinical Relevance—The questionnaire
was intended to facilitate rapid, sensitive, and
accurate rating of a comprehensive range of relevant
domains by naïve raters with minimal burden on
respondents. The principles underlying the development
and design of this structured questionnaire offer
a novel approach to the proxy measurement of HRQL
and changes in HRQL associated with chronic pain for
a range of animal species.
Impact for Human Medicine—This novel approach
may be applicable to other nonverbal populations (eg,
young children or elderly people with cognitive impairment).
(Am J Vet Res 2004;65;1077–1084)