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Journal of Neuro-Oncology - Craniopharyngiomas are locally-aggressive tumors arising along the hypothalamic-pituitary axis. Treatment is nuanced as a result of their proximity and adherence to...  相似文献   
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In some diseases, such as multiple sclerosis, lesion counts obtained from magnetic resonance imaging (MRI) are used as markers of disease progression. This leads to longitudinal, and typically overdispersed, count data outcomes in clinical trials. Models for such data invariably include a number of nuisance parameters, which can be difficult to specify at the planning stage, leading to considerable uncertainty in sample size specification. Consequently, blinded sample size re-estimation procedures are used, allowing for an adjustment of the sample size within an ongoing trial by estimating relevant nuisance parameters at an interim point, without compromising trial integrity. To date, the methods available for re-estimation have required an assumption that the mean count is time-constant within patients. We propose a new modeling approach that maintains the advantages of established procedures but allows for general underlying and treatment-specific time trends in the mean response. A simulation study is conducted to assess the effectiveness of blinded sample size re-estimation methods over fixed designs. Sample sizes attained through blinded sample size re-estimation procedures are shown to maintain the desired study power without inflating the Type I error rate and the procedure is demonstrated on MRI data from a recent study in multiple sclerosis.  相似文献   
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Objective: To identify behavioural barriers of service provision within general practice that may be impacting the vaccination coverage rates of Aboriginal children in Perth, Western Australia (WA). Methods: A purposive developed survey was distributed to 316 general practices across Perth and three key informant interviews were conducted using a mixed‐methods approach. Results: Of the surveyed participants (n=101), 67.4% were unaware of the low vaccination coverage in Aboriginal children; 64.8% had not received cultural sensitivity training in their workplace and 46.8% reported having inadequate time to follow up overdue child vaccinations. Opportunistic vaccination was not routinely performed by 30.8% of participants. Key themes identified in the interviews were awareness, inclusion and cultural safety. Conclusion: Inadequate awareness of the current rates, in association with a lack of cultural safety training, follow‐up and opportunistic practice, may be preventing greater vaccination uptake in Aboriginal children in Perth. Cultural safety is a critical component of the acceptability and accessibility of services; lack of awareness may restrict the development of strategies designed to equitably address low coverage. Implications: The findings of this study provide an opportunity to raise awareness among clinicians in general practice and inform future strategies to equitably deliver targeted vaccination services to Aboriginal children.  相似文献   
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Therapist-report measures of evidence-based interventions have enormous potential utility as quality indicators in routine care; yet, few such tools have shown strong psychometric properties. This study describes reliability and validity characteristics of a therapist-report measure of family therapy techniques for treating adolescent conduct and substance use problems: Inventory of Therapy Techniques for Core Elements of Family Therapy (ITT-CEFT). Study participants included 31 staff therapists treating 68 adolescent clients in eight community-based mental health and substance use clinics. Therapists submitted ITT-CEFT checklists and companion audio recordings for 189 sessions. The ITT-CEFT contains 13 techniques identified as core elements of three manualized family therapy models that are empirically supported for the target group. Therapists also reported on their use of three motivational interventions, and independent observers coded the submitted recordings. ITT-CEFT factor validity was shown via confirmatory factor analyses of the tool’s theoretical structure. Derived modules were: Family Engagement (four items; Cronbach’s α?=?.72); Relational Orientation (five items; α?=?.74); and Interactional Change (four items; α?=?.66). Concurrent validity analyses showed fair-to-excellent therapist reliability compared to observer ratings (ICCs range .64–.75); they showed moderate therapist accuracy compared to observer mean scores, reflecting a tendency to overestimate delivery of the techniques. Discriminant validity analyses showed tool differentiation from motivational interventions. Results offer provisional evidence for the feasibility of using the therapist-report ITT-CEFT to anchor quality procedures for family therapy interventions in real-world settings.

Trial Registration: The parent clinical trial is registered at www.ClinicalTrials.gov, ID: NCT03342872 (registration date: 11.10.17).

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N-myc downstream-regulated gene 2 (NDRG2) is down-regulated in grade-III meningioma [anaplastic meningioma (AM)] and associated with clinically aggressive  相似文献   
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