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Canadian Physiotherapists' Views on Certification, Specialisation, Extended Role Practice, and Entry-Level Training in Rheumatology

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2009
Abstract: 

Background: Since the last decade there has been a gradual change of boundaries of health professionsin providing arthritis care. In Canada, some facilities have begun to adopt new arthritis care models, someof which involve physiotherapists (PT) working in extended roles. However, little is known about PTs'interests in these new roles. The primary objective of this survey was to determine the interests amongorthopaedic physiotherapists (PTs) in being a certified arthritis therapist, a PT specialized in arthritis, oran extended scope practitioner in rheumatology, and to explore the associated factors, including thecoverage of arthritis content in the entry-level physiotherapy training.Methods: Six hundred PTs practicing in orthopaedics in Canada were randomly selected to receive apostal survey. The questionnaire covered areas related to clinical practice, perceptions of rheumatologytraining received, and attitudes toward PT roles in arthritis care. Logistic regression models weredeveloped to explore the associations between PTs' interests in pursuing each of the three extendedscope practice designations and the personal/professional/attitudinal variables.Results: We received 286 questionnaires (response rate = 47.7%); 258 contained usable data. Theaverage length of time in practice was 15.4 years (SD = 10.4). About 1 in 4 PTs agreed that they wereinterested in assuming advanced practice roles (being a certified arthritis therapist = 28.9%, being a PTspecialized in rheumatology = 23.3%, being a PT practitioner = 20.9%). Having a caseload of ≥ 40% inarthritis, having a positive attitude toward advanced practice roles in arthritis care and toward the formalcredentialing process, and recognizing the difference between certification and specialisation wereassociated with an interest in pursing advanced practice roles.Conclusion: Orthopaedic PTs in Canada indicated a fair level of interest in pursuing certification,specialisation and extended scope practice roles in arthritis care. Future research should focus on theeffectiveness and cost-effectiveness of the emerging health service delivery models involving certified,specialized or extended scope practice PTs in the management of arthritis.

Document type: 
Article

Assessment of Health-Related Quality of Life in Arthritis: Conceptualization and Development of Five Item Banks using Item Response Theory

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2006
Abstract: 

Background: Modern psychometric methods based on item response theory (IRT) can be used to developadaptive measures of health-related quality of life (HRQL). Adaptive assessment requires an item bank for eachdomain of HRQL. The purpose of this study was to develop item banks for five domains of HRQL relevant toarthritis.Methods: About 1,400 items were drawn from published questionnaires or developed from focus groups andindividual interviews and classified into 19 domains of HRQL. We selected the following 5 domains relevant toarthritis and related conditions: Daily Activities, Walking, Handling Objects, Pain or Discomfort, and Feelings.Based on conceptual criteria and pilot testing, 219 items were selected for further testing. A questionnaire wasmailed to patients from two hospital-based clinics and a stratified random community sample. Dimensionality ofthe domains was assessed through factor analysis. Items were analyzed with the Generalized Partial Credit Modelas implemented in Parscale. We used graphical methods and a chi-square test to assess item fit. Differential itemfunctioning was investigated using logistic regression.Results: Data were obtained from 888 individuals with arthritis. The five domains were sufficientlyunidimensional for an IRT-based analysis. Thirty-one items were deleted due to lack of fit or differential itemfunctioning. Daily Activities had the narrowest range for the item location parameter (-2.24 to 0.55) and HandlingObjects had the widest range (-1.70 to 2.27). The mean (median) slope parameter for the items ranged from 1.15(1.07) in Feelings to 1.73 (1.75) in Walking. The final item banks are comprised of 31–45 items each.Conclusion: We have developed IRT-based item banks to measure HRQL in 5 domains relevant to arthritis. Theitems in the final item banks provide adequate psychometric information for a wide range of functional levels ineach domain.

Document type: 
Article

A Comparison of Five Methods for Selecting Tagging Single-Nucleotide Polymorphisms

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2005
Abstract: 

Our goal was to compare methods for tagging single-nucleotide polymorphisms (tagSNPs) withrespect to the power to detect disease association under differing haplotype-disease associationmodels. We were also interested in the effect that SNP selection samples, consisting of eithercases, controls, or a mixture, would have on power. We investigated five previously describedalgorithms for choosing tagSNPS: two that picked SNPs based on haplotype structure (Chapmanhaplotypicand Stram), two that picked SNPs based on pair-wise allelic association (Chapman-allelicand Cousin), and one control method that chose equally spaced SNPs (Zhai). In two diseaseassociatedregions from the Genetic Analysis Workshop 14 simulated data, we tested theassociation between tagSNP genotype and disease over the tagSNP sets chosen by each methodfor each sampling scheme. This was repeated for 100 replicates to estimate power. The two allelicmethods chose essentially all SNPs in the region and had nearly optimal power. The two haplotypicmethods chose about half as many SNPs. The haplotypic methods had poor performance comparedto the allelic methods in both regions. We expected an improvement in power when the selectionsample contained cases; however, there was only moderate variation in power between thesampling approaches for each method. Finally, when compared to the haplotypic methods, thereference method performed as well or worse in the region with ancestral disease haplotypestructure.

Document type: 
Article