Paper 1: Psychometric evaluation of the canine briefpain inventory in a Swedish sample of dogs with pain related to osteoarthritis.A. Essner et al.. 2017.Patient group: 61 dogs referred for physiotherapy treatment of osteoarthritis. Somedogs were also receiving ongoing anti-inflammatory treatment.
Control group of21 dogs with no signs of osteoarthritis. Inclusion criteria of: greater than 1year and 9kg, signs and radiographic evidence of osteoarthritis. Exclusioncriteria of: other diseases interfering with mobility or quality of life, lackof understanding of Swedish language. Study type: Observational and cross-sectional study. Canine brief pain inventory(CBPI) translated into Swedish. Questionnaire completed by owner consisting of4 questions on pain severity, and 6 questions on pain interference withfunction. Sums of each section averaged to give pain severity and interferencescores.
Outcomes: Results from 79 adult dogsanalysed as 3 incomplete completions of questionnaires. Analysis ofdemographic data on age and body condition score and internal consistency andconstruct validity were measured.Key results: Dogs affected by osteoarthritis had significantly higher CBPI totalsums, compared to clinically sound dogs, indicating good internal consistency.
The CBPI indicated that a single modality anti-inflammatory treatment wasinadequate at controlling pain in a number of dogs with osteoarthritis. Thereis some overlap with questions as some seemed to assess both pain interferenceand severity. Study weaknesses: Small sample size for factor analysis. Floor effect present, especiallyin pain severity questions, which could indicate subtle behavioural signs ofpain not being recognised.
Paper 2: Psychometric testing of the Helsinki chronicpain index by completion of a questionnaire in Finnish by owners of dogs withchronic signs of pain caused by osteoarthritis. A. Hielm-Björkman et al.. 2009. Patient group: 61 client owneddogs with Osteoarthritis.
Of these, two smaller groups of dogs were treatedwith carprofen (n=17) or placebo (n=17). Studytype: Cohort Study. 61 dogs withchronic signs of osteoarthritis were chosen. Owners were asked questions fromthe Helsinki Chronic Pain Index (HCPI). The questionnaire was asked five timesat four week intervals. Sensitivity testing was performed with smallergroups of dogs (17 each) treated with carprofen or placebo. Outcomes: Owners were asked11 questions and answers were chosen on a 5-point scale.
Answers were laterassigned values 0-4 and summed. Owners also assessed lameness using a visualanalogue score and quality of life. Keyresults: The HCPI correlated wellwith changes in quality of life indicating this tool can be used as apredictive indicator of chronic pain. There were significant pain scoringdifferences between the placebo control group and the carprofen group showingthat the test had high sensitivity. Study weaknesses: Small study samplewith a minimal and short questionnaire.
Seven owners believed their dogs hadtoo much pain before medication and gave their dogs NSAIDs against request fromthe authors, which would have reduced signs of pain, possibly leading to areduced pain score. Paper 3: Validation of a client-based clinicalmetrology instrument for the evaluation of canine elbowOsteoarthritis. C. Hercock et al.. 2009.
Patient group: 26 Labradors with chronic osteoarthritis inthe elbow from 24 clients. Study type: Prospective cohort study. Owners were askedto fill in a LOAD questionnaire assessing the animals function over theprevious two days before data was collected on the force platform to giveresults for PVF Outcomes: After the initial questionnaire, the methodwas repeated two weeks later and repeatability was assessed using intraclasscorrelation coefficient. Before the third visit, medication was ceased untilthe assessment had taken place to give a placebo. Repeatability of thequestionnaire was good. Key results: The results showed the validity of theaggregate score of the LOAD questionnaire compared to the PVF score was poorafter both visits.
Visual lameness scores do not have a linear relationshipwith PVF. A Placebo effect was detected when owners used the LOAD questionnairebut no effect was detected with the PVF data. Study weaknesses: The study only assessed elbow osteoarthritis and small sample size ofonly Labradors and clients from Liverpool. The study states that it was clearthat some owners had difficulty answering questions related to toileting andclimbing stairs/furniture, resulting in values being missed on thequestionnaire. The study didn’t achieve proof of validity and Type II error wasidentified. Paper 4: Evaluation ofConstruct and Criterion Validity for the ‘Liverpool Osteoarthritis in Dogs'(LOAD) Clinical Metrology Instrument and Comparison to Two Other Instruments.M. Walton et al.
. 2013. Patient group: 222 dogs withosteoarthritis.
Study type: Prospective study,split into cross-sectional (n= 143) and longitudinal cohorts (n= 79). Outcomes: Osteoarthritisassessment was undertaken using LOAD, CBPI and HCPI. Results were thencompared between instruments. The results were also compared to the goldstandard, which is cited in this paper as the measurement of ground reactionforces using force plate analysis. Key results: The results of thethree methods correlated well, providing construct validity. This isunsurprising due to the similarity of the tests, as all use subtleties of themain clinical signs of canine osteoarthritis as their underlying theoreticalbasis. LOAD is considered a useful tool for use by owners, as the resultsappear reliable whilst remaining simple and comprehensible.
BothLOAD and CBPI were suggested to have good criterion validity due to asignificant, although weak, correlation between their analysis ofosteoarthritis and that produced using force plate analysis. There is noapparent reason as to why the HCPI did not correlate significantly. Study weaknesses: The primary purposeof this study was to determine the validity of LOAD, possibly leading to biasregarding the other tools. The longitudinal cohort was small leading to limitedstatistical analysis.
Learned behaviour and gait changes may have masked themeasurable effects of the arthritis. Paper 5: Validation of a structured questionnaire asan instrument to measure chronic pain in dogs on the basis of effects on health-relatedquality of life. M. Wiseman-Orr et al.. 2006. Patient group: 108 dogs affected by degenerative jointdisease (DJD), 26 clinically healthy dogs.
Study type: Longitudinal study. Initial questionnaireswere completed by owners of dogs with DJD in the first consultation, andmodified questionnaires were at subsequent consultations. Modified initial andfurther modified subsequent questionnaires were completed for clinicallyhealthy dogs. Questionnaire baseis were a 109 descriptor item and 0-6Likert-type ranking scale. Where appropriate, questions regarding behaviouralchanges and health related quality of life (HRQL) were included. Clinicianquestionnaires rating patient pain 1-10, with follow-up Likert-type scalequestionnaires, were also provided.
Outcomes: 90 of the DJD cohort dogs were enrolled and73 provided a minimum of 1 follow up questionnaire. 26 clinically healthy dogswere included, with a follow up questionnaire from 16. Factor analysis wasperformed on a total of 221 questionnaires with a scree plot suggesting 7factors accounted for the data variance but Kaiser criterion suggested a 15factor model. Key results: 12 factors accounting for 65% of datavariance were identified as key HRQL domains.
Linear discriminant analysis ofthese HRQL domains discriminated successfully between no pain and some paindogs in 88% cases (95% no pain; 87 % some pain). Study weaknesses: In depth questionnaire format resulted inexclusion due to missed questions.