131 research outputs found

    Understanding the effect of sheared flow on microinstabilities

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    The competition between the drive and stabilization of plasma microinstabilities by sheared flow is investigated, focusing on the ion temperature gradient mode. Using a twisting mode representation in sheared slab geometry, the characteristic equations have been formulated for a dissipative fluid model, developed rigorously from the gyrokinetic equation. They clearly show that perpendicular flow shear convects perturbations along the field at a speed we denote by McsMc_s (where csc_s is the sound speed), whilst parallel flow shear enters as an instability driving term analogous to the usual temperature and density gradient effects. For sufficiently strong perpendicular flow shear, M>1M >1, the propagation of the system characteristics is unidirectional and no unstable eigenmodes may form. Perturbations are swept along the field, to be ultimately dissipated as they are sheared ever more strongly. Numerical studies of the equations also reveal the existence of stable regions when M<1M < 1, where the driving terms conflict. However, in both cases transitory perturbations exist, which could attain substantial amplitudes before decaying. Indeed, for M1M \gg 1, they are shown to exponentiate M\sqrt{M} times. This may provide a subcritical route to turbulence in tokamaks.Comment: minor revisions; accepted to PPC

    A cross-sectional testing of The Iowa Personality Disorder Screen in a psychiatric outpatient setting

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    <p>Abstract</p> <p>Background</p> <p>Patients suspected of personality disorders (PDs) by general practitioners are frequently referred to psychiatric outpatient clinics (POCs). In that setting an effective screening instrument for PDs would be helpful due to resource constraints. This study evaluates the properties of The Iowa Personality Disorder Screen (IPDS) as a screening instrument for PDs at a POC.</p> <p>Methods</p> <p>In a cross-sectional design 145 patients filled in the IPDS and were examined with the SCID-II interview as reference. Various case-findings properties were tested, interference of socio-demographic and other psychopathology were investigated by logistic regression and relationships of the IPDS and the concept of PDs were studied by a latent variable path analysis.</p> <p>Results</p> <p>We found that socio-demographic and psychopathological factors hardly disturbed the IPDS as screening instrument. With a cut-off ≥4 the 11 items IPDS version had sensitivity 0.77 and specificity 0.71. A brief 5 items version showed sensitivity 0.82 and specificity 0.74 with cut-off ≥ 2. With exception for one item, the IPDS variables loaded adequately on their respective first order variables, and the five first order variables loaded in general adequately on their second order variable.</p> <p>Conclusion</p> <p>Our results support the IPDS as a useful screening instrument for PDs present or absent in the POC setting.</p

    Experiences of parenting and clinical intervention for mothers affected by personality disorder: a pilot qualitative study combining parent and clinician perspectives

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    Background: Evidence-based parenting programmes are recommended for the treatment of child mental health difficulties. Families with complex psychosocial needs show poorer retention and outcomes when participating in standard parenting programmes. The Helping Families Programme (HFP) is a 16-week community-based parenting intervention designed to meet the needs of these families, including families with parental personality disorder. This study aimed to explore the help seeking and participatory experiences of parents with a diagnosis of personality disorder. It further aimed to examine the acceptability of referral and intervention processes for the HFP from the perspectives of (i) clinicians referring into the programme; and (ii) referred parents. Method: Semi-structured interviews were conducted with parents recruited to receive HFP (n = 5) as part of a research case series and the referring NHS child and adolescent mental health service (CAMHS) clinicians (n = 5). Transcripts were analysed using Interpretive Phenomenological Analysis. Results: Four themes were identified for parents: (i) the experience of parenthood, (ii) being a parent affected by personality disorder, (iii) experience of the intervention, and (iv) qualities of helping. Three themes emerged for clinicians: (i) challenges of addressing parental need, (ii) experience of engaging parents with personality disorders and (iii) limited involvement during HFP. Comparison of parent and clinician themes led to the identification of two key interlinked themes: (i) concerns prior to receiving the intervention, and (ii) the challenges of working together without a mutual understanding. Conclusions: This pilot study identifies potentially significant challenges of working with parents affected by personality disorder and engaging them in HFP and other similar interventions. Results have important wider clinical implications by highlighting potential barriers to engagement and participation and providing insights on how these barriers might be overcome. Findings have been used to inform the referral and intervention processes of a pilot RCT and further intervention development

    Design of a multicentered randomized controlled trial on the clinical and cost effectiveness of schema therapy for personality disorders

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    <p>Abstract</p> <p>Background</p> <p>Despite international guidelines describing psychotherapy as first choice for people with personality disorders (PDs), well-designed research on the effectiveness and cost-effectiveness of psychotherapy for PD is scarce. Schema therapy (ST) is a specific form of psychological treatment that proved to be effective for borderline PD. Randomized controlled studies on the effectiveness of ST for other PDs are lacking. Another not yet tested new specialized treatment is Clarification Oriented Psychotherapy (COP). The aim of this project is to perform an effectiveness study as well as an economic evaluation study (cost effectiveness as well as cost-utility) comparing ST versus COP versus treatment as usual (TAU). In this study, we focus on avoidant, dependent, obsessive-compulsive, paranoid, histrionic and narcissistic PD.</p> <p>Methods/Design</p> <p>In a multicentered randomized controlled trial, ST, and COP as an extra experimental condition, are compared to TAU. Minimal 300 patients are recruited in 12 mental health institutes throughout the Netherlands, and receive an extensive screening prior to enrolment in the study. When eligible, they are randomly assigned to one of the intervention groups. An economic evaluation and a qualitative research study on patient and therapist perspectives on ST are embedded in this trial. Outcome assessments (both for clinical effectiveness and economic evaluation) take place at 6,12,18,24 and 36 months after start of treatment. Primary outcome is recovery from PD; secondary measures include general psychopathological complaints, social functioning and quality of life. Data for the cost-effectiveness and cost-utility analyses are collected by using a retrospective cost interview. Information on patient and therapist perspectives is gathered using in-depth interviews and focus groups, and focuses on possible helpful and impeding aspects of ST.</p> <p>Discussion</p> <p>This trial is the first to compare ST and COP head-to-head with TAU for people with a cluster C, paranoid, histrionic and/or narcissistic PD. By combining clinical effectiveness data with an economic evaluation and with direct information from primary stakeholders, this trial offers a complete and thorough view on ST as a contribution to the improvement of treatment for this PD patient group.</p> <p>Trial registration</p> <p>Netherlands Trial Register (NTR): <a href="http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=566">NTR566</a></p

    Standard set of patient-reported outcomes for personality disorder

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    Purpose The purpose of the article is to present standard set of outcomes for people with personality disorder (PD), in order to facilitate patient outcome measurement worldwide. Methods The International Consortium for Health Outcomes Measurement (ICHOM) gathered a multidisciplinary international working group, consisting of 16 experts, including clinicians, nurses, psychologists, methodologists and patient representatives, to develop a standard set of outcome measures for people with PD. The Delphi method was used to reach consensus on the scope of the set, outcome domains, outcome measures, case-mix variables and time points for measuring outcomes in service users. For each phase, a project team prepared materials based on systematic literature reviews and consultations with experts. Results The working group decided to include PD, as defined by International Classification of Diseases 11th revision (ICD-11). Eleven core outcomes and three optional outcomes across four health domains (mental health, behaviour, functioning and recovery) were defined as those relevant for people with PD. Validated measures for the selected outcomes were selected, some covering more than one outcome. Case-mix variables were aligned to other ICHOM mental health standard sets and consisted of demographic factors and those related to the treatment that people received. The group recommended that most outcomes are measured at baseline and annually. Conclusion The international minimum standard set of outcomes has the potential to improve clinical decision making through systematic measurement and comparability. This will be key in improving the standard of health care for people with PD across the world

    Evaluating a Measure of Social Health Derived from Two Mental Health Recovery Measures: The California Quality of Life (CA-QOL) and Mental Health Statistics Improvement Program Consumer Survey (MHSIP)

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    Social health is important to measure when assessing outcomes in community mental health. Our objective was to validate social health scales using items from two broader commonly used measures that assess mental health outcomes. Participants were 609 adults receiving psychological treatment services. Items were identified from the California Quality of Life (CA-QOL) and Mental Health Statistics Improvement Program (MHSIP) outcome measures by their conceptual correspondence with social health and compared to the Social Functioning Questionnaire (SFQ) using correlational analyses. Pearson correlations for the identified CA-QOL and MSHIP items with the SFQ ranged from .42 to .62, and the identified scale scores produced Pearson correlation coefficients of .56, .70, and, .70 with the SFQ. Concurrent validity with social health was supported for the identified scales. The current inclusion of these assessment tools allows community mental health programs to include social health in their assessments
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