337 research outputs found

    A Metric Framework for quantifying Data Concentration

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    Poor performance of artificial neural nets when applied to credit-related classification problems is investigated and contrasted with logistic regression classification. We propose that artificial neural nets are less successful because of the inherent structure of credit data rather than any particular aspect of the neural net structure. Three metrics are developed to rationalise the result with such data. The metrics exploit the distributional properties of the data to rationalise neural net results. They are used in conjunction with a variant of an established concentration measure that differentiates between class characteristics. The results are contrasted with those obtained using random data, and are compared with results obtained using logistic regression. We find, in general agreement with previous studies, that logistic regressions out-perform neural nets in the majority of cases. An approximate decision criterion is developed in order to explain adverse results

    Excessive Daytime Sleepiness in Obstructive Sleep Apnea Patients Treated With Continuous Positive Airway Pressure: Data From the European Sleep Apnea Database

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    Excessive daytime sleepiness (EDS) is a symptom of obstructive sleep apnea (OSA) that resolves under treatment with continuous positive airway pressure (CPAP). In some patients, sleepiness persists despite CPAP treatment. We retrospectively analyzed data on subjective residual EDS, assessed as an Epworth Sleepiness Scale score (ESS) >10, in patients from the European Sleep Apnea Database (n = 4,853, mean age ± SD 54.8 ± 11.8 years, 26.1% females), at baseline and at the first visit (median follow-up: 5 months, interquartile range 3–13). An ESS > 10 occurred in 56% of patients at baseline and in 28.2% of patients at follow-up. Residual EDS was analyzed in 2,190 patients (age: 55.1 ± 12.0 years, 26.1% females) with sleep monitoring data (median follow-up: 3 months, interquartile range 1–15). Sleep studies during CPAP use were obtained in 58% of these patients; EDS was reported by 47.2% of patients at baseline and by 30.3% at follow-up. Residual OSA, defined as an apnea–hypopnea index >10/h, and insufficient CPAP adherence, defined as nightly use <4 h, occurred with similar frequency in patients with and without EDS at follow-up. Prevalence of residual EDS was highest (40%) in patients with a first follow-up visit at 0–3 months, then it was 13–19% in patients with a first follow-up visit after 4 months to 2 years. The change in ESS (n = 2,190) was weakly correlated with CPAP use (R2 = 0.023, p < 0.0001). Logistic regression showed that an ESS score >10 at the first follow-up visit was associated directly with ESS at baseline and inversely with duration of follow-up, and CPAP use (R2 of the model: 0.417). EDS showed heterogeneity in different European countries both at baseline and at the first follow-up visit, suggesting modulation by cultural and lifestyle factors. In conclusion, residual EDS in CPAP-treated OSA occurred in approximately one in four patients at follow-up; its prevalence was highest (40%) in the first 3 months of treatment and subsequently decreased. The finding of residual EDS in a significant percentage of optimally treated OSA patients suggests that wake-promoting agents may be useful, but their indication should be evaluated after at least 3 months of treatment

    Acceptability and feasibility of a Community Outpatient Psychotherapy Engagement Service for Self-harm: COPESS a mixed methods study

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    Background: Self-harm refers to any intentional self-injury or self-poisoning, with or without the intention to end one’s life. People who self-harm are at high risk of suicide, and often experience a range of social and mental health issues as well as considerable emotional distress. Around 70% of people who self-harm also experience symptoms of depression. There is very little help available from health and mental health services designed specifically for people who self-harm, and many receive no help at all. Most self-harm happens in the community but there have been very few attempts to develop self-harm specific services in community settings, such as GP practices. Readily accessible brief talking therapies show promise in helping people who self-harm, but further evaluation of these approaches is needed. The Community Outpatient Psychological Engagement Service for Self-Harm (COPESS) is a brief talking therapy intervention for depression and self-harm. Objectives: The objectives were to assess the feasibility of conducting a trial of the COPESS intervention in a community setting in relation to participant recruitment, data collection, the acceptability of the intervention and retention in treatment and study. Design: A mixed-method study, using a single-blind randomised controlled trial (RCT), assessing the acceptability and feasibility of the COPESS intervention for people with depression who self-harm, and purposefully collected qualitative data. Setting: GP practices in Northwest England. Participants: Individuals aged >16 years who had depression and self-harmed in previous six months. Interventions: The COPESS intervention is a psychological ‘talking’ therapy designed to help people who self-harm. It is made up of a short course of sessions with a therapist, that are available quickly after self-harm has been identified by that person’s GP. People were randomised 1:1 to receive either COPESS plus treatment-as-usual (TAU) or TAU alone. Main outcome measures: The primary outcome was the feasibility and acceptability of COPESS for people in the community with self-harm and co-existing depression. Secondary outcome measures were assessed at baseline, with follow-up assessments occurring at 1- month, 2-months and 3-months. Results: Findings indicated that COPESS was both acceptable and feasible, with all progression criteria being met. Fifty-seven people were recruited into the trial. Fifty-five were then randomly allocated to receive either the COPESS therapy (28 people) or treatment as usual only (27 people). Primary care staff and COPESS therapists based in a 3 mental health trust reported the intervention fitted and complemented existing services, and patients reported that they favoured the rapid, self-harm focused, person-centred approach of the intervention. The response to the therapy was very positive, with most participants attending all sessions. There were early indications that receiving COPESS may lower levels of depression, general distress and urges to self-harm compared to treatment as usual. Qualitative interviews were completed with participants, therapists, and primary care staff and feedback was positive about the COPESS intervention. Limitations: Due to the COVID-19 pandemic the COPESS intervention was delivered remotely only, therefore the experiences of the patients in the feasibility trial may not be representative of therapy delivered in person. Furthermore, the pandemic and associated disease control measures (i.e., lockdowns) may have had a general impact on outcomes, including recruitment into the study (both GP surgeries and participants), and experiences of participants and therapists. Conclusions: All progression criteria were met supporting further evaluation of the intervention in a full-scale clinical effectiveness trial. COPESS has potential as a brief primary-care based intervention for those struggling with self-harm. Future work: Further work involving stakeholder engagement is needed to refine the delivery of the intervention across multiple sites and conduct a full-scale efficacy trial. Trial registration: NCT04191122. Funding details: This project was funded by the National Institute for Health and Care Research (NIHR200543) Research for Patient Benefit Programme

    Methods for specifying the target difference in a randomised controlled trial : the Difference ELicitation in TriAls (DELTA) systematic review

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    Peer reviewedPublisher PD

    Collaboration with general practitioners: preferences of medical specialists – a qualitative study

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    BACKGROUND: Collaboration between general practitioners (GPs) and specialists has been the focus of many collaborative care projects during the past decade. Unfortunately, quite a number of these projects failed. This raises the question of what motivates medical specialists to initiate and continue participating with GPs in new collaborative care models. The following question is addressed in this study: What motivates medical specialists to initiate and sustain new models for collaborating with GPs? METHODS: We conducted semi-structured interviews with eighteen medical specialists in the province of Groningen, in the North of The Netherlands. The sampling criteria were age, gender, type of hospital in which they were practicing, and specialty. The interviews were recorded, fully transcribed, and analysed by three researchers working independently. The resulting motivational factors were grouped into categories. RESULTS: 'Teaching GPs' and 'regulating patient flow' (referrals) appeared to dominate when the motivational factors were considered. In addition, specialists want to develop relationships with the GPs on a more personal level. Most specialists believe that there is not much they can learn from GPs. 'Lack of time', 'no financial compensation', and 'no support from colleagues' were considered to be the main concerns to establishing collaborative care practices. Additionally, projects were often experienced as too complex and time consuming whereas guidelines were experienced as too restrictive. CONCLUSION: Specialists are particularly interested in collaborating because the GP is the gatekeeper for access to secondary health care resources. Specialists feel that they are able to teach the GPs something, but they do not feel that they have anything to learn from the GPs. With respect to professional expertise, therefore, specialists do not consider GPs as equals. Once personal relationships with the GPs have been established, an informal network with incidental professional contact seems to be sufficient to satisfy the collaborative needs of the specialist. The concerns seem to outweigh any positive motivational forces to developing new models of collaborative practice

    Characterisation of proteins in excretory/secretory products collected from salmon lice, Lepeophtheirus salmonis

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    Background  The salmon louse, Lepeophtheirus salmonis, is an ectoparasitic copepod which feeds on the mucus, skin and blood of salmonid fish species. The parasite can persist on the surface of the fish without any effective control being exerted by the host immune system. Other ectoparasitic invertebrates produce compounds in their saliva, excretions and/or secretions which modulate the host immune responses allowing them to remain on or in the host during development. Similarly, compounds are produced in secretions of L. salmonis which are thought to be responsible for immunomodulation of the host responses as well as other aspects of crucial host-parasite interactions.  Methods  In this study we have identified and characterised the proteins in the excretory/secretory (E/S) products of L. salmonis using LC-ESI-MS/MS.  Results  In total 187 individual proteins were identified in the E/S collected from adult lice and pre-adult sea lice. Fifty-three proteins, including 13 serine-type endopeptidases, 1 peroxidase and 5 vitellogenin-like proteins were common to both adult and pre-adult E/S products. One hundred and seven proteins were identified in the adult E/S but not in the pre-adult E/S and these included serine and cysteine-type endopeptidases, vitellogenins, sphingomyelinase and calreticulin. A total of 27 proteins were identified in pre-adult E/S products but not in adult E/S.  Conclusions  The assigned functions of these E/S products and the potential roles they play in host-parasite interaction is discussed

    Motives and preferences of general practitioners for new collaboration models with medical specialists: a qualitative study

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    BACKGROUND: Collaboration between general practitioners (GPs) and specialists has been the focus of many collaborative care projects during the past decade. Unfortunately, quite a number of these projects failed. This raises the question of what motivates GPs to initiate and continue participating with medical specialists in new collaborative care models. The following two questions are addressed in this study: What motivates GPs to initiate and sustain new models for collaborating with medical specialists? What kind of new collaboration models do GPs suggest? METHODS: A qualitative study design was used. Starting in 2003 and finishing in 2005, we conducted semi-structured interviews with a purposive sample of 21 Dutch GPs. The sampling criteria were age, gender, type of practice, and practice site. The interviews were recorded, fully transcribed, and analysed by two researchers working independently. The resulting motivational factors and preferences were grouped into categories. RESULTS: 'Developing personal relationships' and 'gaining mutual respect' appeared to dominate when the motivational factors were considered. Besides developing personal relationships with specialists, the GPs were also interested in familiarizing specialists with the competencies attached to the profession of family medicine. Additionally, they were eager to increase their medical knowledge to the benefit of their patients. The GPs stated a variety of preferences with respect to the design of new models of collaboration. CONCLUSION: Developing personal relationships with specialists appeared to be one of the dominant motives for increased collaboration. Once the relationships have been formed, an informal network with occasional professional contact seemed sufficient. Although GPs are interested in increasing their knowledge, once they have reached a certain level of expertise, they shift their focus to another specialty. The preferences for new collaboration models are diverse. A possible explanation for the differences in the preferences is that professionals are more knowledge driven than organisation driven as the acquiring of new knowledge is considered more important than the route by which this is achieved. A new collaboration model seems a way to acquire knowledge. Once this is achieved the importance of a model possibly diminishes, whereas the professional relationships last

    Clinical Phenotypes and Comorbidity in European Sleep Apnoea Patients

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    Background Clinical presentation phenotypes of obstructive sleep apnoea (OSA) and their association with comorbidity as well as impact on adherence to continuous positive airway pressure (CPAP) treatment have not been established. Methods A prospective follow-up cohort of adult patients with OSA (apnoea-hypopnoea index (AHI) of 655/h) from 17 European countries and Israel (n = 6,555) was divided into four clinical presentation phenotypes based on daytime symptoms labelled as excessive daytime sleepiness ("EDS") and nocturnal sleep problems other than OSA (labelled as "insomnia"): 1) EDS (daytime+/nighttime-), 2) EDS/insomnia (daytime+/nighttime+), 3) non-EDS/noninsomnia (daytime-/nighttime-), 4) and insomnia (daytime-/nighttime+) phenotype. Results The EDS phenotype comprised 20.7%, the non-EDS/non-insomnia type 25.8%, the EDS/ insomnia type 23.7%, and the insomnia phenotype 29.8% of the entire cohort. Thus, clinical presentation phenotypes with insomnia symptoms were dominant with 53.5%, but only 5.6% had physician diagnosed insomnia. Cardiovascular comorbidity was less prevalent in the EDS and most common in the insomnia phenotype (48.9% vs. 56.8%, p<0.001) despite more severe OSA in the EDS group (AHI 35.0\ub125.5/h vs. 27.9\ub122.5/h, p<0.001, respectively). Psychiatric comorbidity was associated with insomnia like OSA phenotypes independent of age, gender and body mass index (HR 1.5 (1.188-1.905), p<0.001). The EDS phenotype tended to associate with higher CPAP usage (22.7 min/d, p = 0.069) when controlled for age, gender, BMI and sleep apnoea severity. Conclusions Phenotypes with insomnia symptoms comprised more than half of OSA patients and were more frequently linked with comorbidity than those with EDS, despite less severe OSA. CPAP usage was slightly higher in phenotypes with EDS
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