Background Despite the increased deployment and added value of Advanced Practitioner Physiotherapy (APP) in musculoskeletal care internationally, APP is not yet widely accepted within Dutch primary care. This may be due to specific constraints in the implementation of APP within the Dutch healthcare system. This study aimed to explore the experiences and perceptions of Advanced Practitioner Physiotherapists (APPs) and General Practitioners (GPs) with respect to implementing APP within Dutch primary care. Methods This explorative and interpretive qualitative study included 12 APPs and 3 GPs who were in various stages of implementing an APP care model. Semi-structured interviews were conducted between January and March 2021. The topic list was based on existing literature, the personal input of researchers, and the Constellation Approach framework. Data were analysed using a thematic inductive approach. Results Four main themes emerged from the data; 1) Both GPs’ trust in APP and a clear added value of APP are critical for starting implementation, 2) APPs need continuous support from GPs, 3) APPs believe that their position needs strengthening, and 4) Implementation of the APP model creates tension over ownership. These four themes highlight the perceived difficulties in gaining trust, lack of clarity over the added value of APP, ambiguity over APPs’ professional profile and positioning, a need on behalf of GPs to maintain authority, lack of reimbursement structure, and the struggle APPs face to strike a balance with current care. Conclusion This study demonstrates that implementing an APP model of care is challenging, in part, because the deployment of APP does not sufficiently align with the core values of GPs, while GPs appear reluctant to hand over control of elements of patient care to APPs. APPs do not appear to have ownership over the implementation, given their strong dependence on the practice, values and needs of GPs. Trial registration Ethical approval was obtained from the Medical Ethics Committee of VU University Medical Centre in Amsterdam; reference number 2020.17 . All participants were asked to provide written informed consent prior to participating in the study.

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Background: Despite the increasing deployment and added value of Advanced Practitioner in Physiotherapy (APP) in musculoskeletal care internationally, APP is not widely accepted in Dutch primary care yet. This may be due to constraints in the implementation of APP within the Dutch health care system. The aim of this study was to explore experiences and perceptions of APP and General Practitioners (GP) in implementing APP in Dutch primary care. Methods: This was an explorative and interpretive qualitative study among 13 APPs and 3 GPs that were in various stages of implementing an APP care model. Semi-structured interviews were conducted from January to March 2021. The topic list was based on existing literature, personal input of researchers, and the Constellation Approach framework. Data were analysed using a thematic inductive approach.Results: Four main themes emerged from the data; 1) The start-up of an APP practice requires trust and clear added value for the GP, 2) Starting APP must be strongly supported by GP, 3) Positioning of APP is still unclear, and 4) Ownership of patients with musculoskeletal complaints. These four themes put forward perceived difficulties in gaining trust, lack of clarity regarding the added value of APP, ambiguity of the APP’s professional profile and positioning, lack of reimbursement structure, and APP’s struggle in seeking balance with current care. Conclusion: This study shows that the implementation of an APP model of care is challenging. The deployment of APP does not sufficiently align with the core values of GPs, and GPs seem reluctant to hand-over some control over patient care to APPs. APP does not appear to have ownership of the implementation, given its strong dependence on the practice, values and needs of the GP.Trial registration: Ethical approval is obtained from the Medical Ethics Committee of the VU University Medical Centre in Amsterdam; reference number 2020.17. All participants were asked written informed consent before participating in this study.

Background Fractures of lower extremities are common trauma-related injuries, and have major impact on patients' functional status. A frequently used Patient-Reported Outcome Measure (PROM) to evaluate patients’ functional status with lower extremity fractures is the Lower Extremity Functional Scale (LEFS). However, there is no systematic review regarding content validity and other measurement properties of the LEFS in patients with lower extremity fractures. Methods A search was performed in PubMed, Embase, Scopus, and Cochrane Library from inception until November 2020. Studies on development of the LEFS and/or the evaluation of one or more measurement properties of the LEFS in patients with lower extremity fractures were included, and independently assessed by two reviewers using COSMIN guidelines. Results Seven studies were included. Content validity of the LEFS was rated 'inconsistent', supported by very low quality of evidence. Structural validity was rated ‘insufficient’ supported by doubtful methodological quality. Internal consistency, measurement error, and responsiveness were rated 'indeterminate' supported by inadequate to adequate methodological quality. The methodological quality of the construct validity (hypotheses testing) assessment was rated as 'inadequate'. Conclusion The LEFS has several shortcomings, the lack of sufficient content validity being the most important one as content validity is considered the most crucial measurement property of a PROM according to the COSMIN guidelines. In interpreting the outcomes, one should therefore be aware that not all relevant aspects of physical functioning may be accounted for in the LEFS. Further validation in a well-designed content validity study is needed, including a clearly defined construct and patient involvement during the assessment of different aspects of content validity. Plain English summary Bone fractures of the lower extremities are a common injury. During rehabilitation it is essential to evaluate how patients experience their physical functioning, in order to monitor the progress and to optimize treatment. To measure physical functioning often questionnaires (also known as Patient Reported Outcome Measures) are used, such as the Lower Extremity Functional Scale (LEFS). However, it is not clear if the LEFS actually measures physical function, and if its other measurement properties are sufficient for using this questionnaire among patients with fractures in the lower extremities. Therefore, we systematically searched and assessed scientific papers on the development of the LEFS (i.e., its ability to measure physical functioning), and papers on the performance of the LEFS with regard to several measurement properties to identify possible factors that may cause measurement errors. Hereby we have assessed the quality of the studies included. Our main finding was that the LEFS may not measure all aspects of p...

Purpose To assess whether regression modeling can be used to predict EQ-5D-3L utility values from the Oswestry Disability Index (ODI) in low back pain (LBP) patients for use in cost-effectiveness analysis. Methods EQ-5D-3L utility values of LBP patients were estimated using their ODI scores as independent variables using regression analyses, while adjusting for case-mix variables. Six different models were estimated: (1) Ordinary Least Squares (OLS) regression, with total ODI score, (2) OLS, with ODI item scores as continuous variables, (3) OLS, with ODI item scores as ordinal variables, (4) Tobit model, with total ODI score, (5) Tobit model, with ODI item scores as continuous variables, and (6) Tobit model, with ODI item scores as ordinal variables. The models’ performance was assessed using explained variance (R2) and root mean squared error (RMSE). The potential impact of using predicted instead of observed EQ-5D-3L utility values on cost-effectiveness outcomes was evaluated in two empirical cost-effectiveness analysis. Results Complete individual patient data of 18,692 low back pain patients were analyzed. All models had a more or less similar R2 (range 45–52%) and RMSE (range 0.21–0.22). The two best performing models produced similar probabilities of cost-effectiveness for a range of willingness-to-pay (WTP) values compared to those based on the observed EQ-5D-3L values. For example, the difference in probabilities ranged from 2 to 5% at a WTP of 50,000 €/QALY gained. Conclusion Results suggest that the ODI can be validly used to predict low back pain patients’ EQ-5D-3L utility values and QALYs for use in cost-effectiveness analyses.