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Mindfulness-based therapies for psychological health conditions : a meta-analysisMcCarney, Robert William January 2010 (has links)
Mindfulness-Based Therapies (MBT) are a current technology within the cognitive behavioural tradition, which can be grouped according to whether mindfulness is a major or a minor component. A mindful approach to psychological difficulties attempts to change the relationship with unwanted inner experience. The model suggests this may help reduce affective symptomatology. There has been a considerable growth of interest in these therapies with an accompanying increase in the evidence base. A number of reviews have been conducted however they have not comprehensively appraised these therapies. The primary aim of my study was to contribute to ongoing research determining the effectiveness of MBT for the treatment of affective symptomatology. Depending on these results, a secondary aim of the study was to make recommendations for the use of MBT in clinical practice. Methods I conducted a meta-analysis which looked separately at therapies considered to have mindfulness as a major component; therapies considered to have mindfulness as a minor component; and a comparison of these two groups. Of the 598 unique citations identified in the literature, 113 were assessed for eligibility and 40 included in the pool of studies for the meta-analysis. Results For the major component therapies, there was a significant mean reduction score in depressive symptomatology as measured by the BDI of 8.73 points (k = 11; 95% CI = 6.61, 10.86). Evidence of effectiveness was also found for the minor component therapies (k = 8) in reducing anxiety symptomatology with a significant standardised mean difference of 1.24 (95% CI = 0.81, 2.10). Discussion I found evidence for the effectiveness of mindfulness-based therapies in reducing levels of depression or anxiety mainly in patients diagnosed with depressive or anxiety disorders. The robustness of these findings is discussed alongside the implications for research and practice within the context of the current literature.
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Systematic review and meta-analysis of animal models of acute ischaemic strokeSena, Emily Shamiso January 2010 (has links)
Ischaemic stroke is responsible for substantial death and disability and creates a huge financial burden for healthcare budgets worldwide. At present there are few effective treatments for acute stroke and these are urgently required. Increased understanding of the ischaemic cascade has generated interest in neuroprotection for focal cerebral ischaemia. However, treatment effects observed in of over 500 interventions in animal models have yet to be translated to the clinic. Systematic review and meta-analysis allows unbiased identification of all relevant data for a given intervention, gives a clearer view of its true efficacy and the limitations to its therapeutic potential. Understanding the reasons for this bench-to-bedside failure and providing quantitative explanations may help to address these discrepancies. Random effects weighted mean difference meta-analysis of six interventions (tirilazad, tPA, NXY-059, Hypothermia, Piracetam and IL1-RA) reported study quality to be consistently low. In some instances, potential sources of bias were associated with overestimations of efficacy. Likewise, clinical trials have tested interventions in conditions where efficacy was not observed in animals. Cumulative meta-analysis suggests that for tPA the estimate of efficacy is stable after the inclusion of data from 1500 animals; hypothermia and FK506 are the only other interventions to have been tested in at least 1500 animals. Meta-regression suggests biological rather methodical factors are better predictors of outcome; a major limitation of these data is the impact of publication bias, and this work suggests effect sizes from met-analyses are inflated by about 31% because 16% of studies remain unpublished. The systematic review and meta-analysis of hypothermia was used to plan experiments investigating the possible impact of pethidine, a drug used to prevent shivering. This in vivo experiment, in which potential sources of bias were minimised, suggests that pethidine does not influence the observed efficacy of hypothermia in an animal model of ischaemic stroke. This thesis reports that animal studies of ischaemic stroke are often not conducted with sufficient rigour. Both minimising potential sources of bias in individual experiments and using meta-analysis to summarise data from a number of experiments may be helpful in improving the translation of neuroprotective efficacy in ischaemic stroke.
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Cortical regions involved in proactive control of task-setStevens, Tobias January 2011 (has links)
This thesis is about what happens in the brain when people switch between tasks. Each task requires a particular assembly of cognitive processes, an orientation of attention and set of rules relating action to input — a "task-set". The research reported used a task-cueing paradigm to study preparatory control of task-set. On each trial a stimulus (a coloured shape) was preceded by a verbal task-cue specifying which task to do (judge the shape or the colour of the stimulus). Reaction time and error rate increase on trials when the task changes relative to trials on which it does not. When the cue stimulus interval (CSI) is increased, this "switch cost" is reduced, indexing a process of task-set reconfiguration in which top-down control is employed to reconfigure the task-set parameters. Effective reconfiguration may also be indicated by a reduction in the "response congruence effect" — poorer performance on stimuli mapped to different responses for the two tasks than for stimuli mapped to the same response. I present six experiments using transcranial magnetic stimulation (TMS), a technique for interfering briefly and harmlessly with neuronal activity in a small region of cortex, to address the question of which brain regions contribute to anticipatory control of task-set as indexed by these behavioural measures. To help guide the selection of candidate brain regions, I first present a review and meta-analysis of neuroimaging studies of task-switching in the literature. Many fMRI studies, comparing brain activation on task-switch and -repeat trials have been published. Some have also tried to isolate activations related specifically to pro-active control of task-set. The activations reported are quite inconsistent over studies. I used a quantitative meta-analysis technique to identify which brain regions are most consistently found by studies reporting switch minus repeat contrasts and which may be specifically important for preparation on switch trials. The experiments examined the effect of stimulating several regions during the long cue-stimulus interval of a task-cueing paradigm, relative to control conditions. A first pair of experiments suggests an important role in proactive task-set control for two regions in dorsal medial frontal cortex, the supplementary motor area (SMA) and an area known as pre-SMA, though the former region appeared to contribute to reducing the switch cost while the latter appeared to reduce the effects of response congruence. In a further three experiments, I examined the role of the right intra-parietal sulcus (rIPS); this appears to play a crucial role in preparation for a task-switch but not post-stimulus task-set reconfiguration. In a final experiment, I used TMS guided by fMRI activations in the same participants to study the effects of stimulation over the left inferior frontal junction (IFJ). The results indicate that a region just anterior to the left IFJ is specifically important for preparing for a switch trial. I discuss the roles that may be played by these three regions in task-set control.
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Insulin resistance and endometrial cancer risk: A systematic review and meta-analysisHernández, Adrian V., Pasupuleti, Vinay, Benites Zapata, Vicente A., Thota, Priyaleela, Deshpande, Abhishek, Perez Lopez, Faustino R. 25 November 2015 (has links)
Abstract Aim: It has been suggested that chronic hyperinsulinemia from insulin resistance is
involved in the etiology of endometrial cancer (EC). We performed a systematic review and
meta-analysis to assess whether insulin resistance is associated with the risk of EC.
Methods: We searched PubMed-Medline, Embase, Scopus, and Web of Science for articles
published from database inception through 30th September 2014. We included all observational
studies evaluating components defining insulin resistance in women with and without
EC. Quality of the included studies was assessed by NewcastleeOttawa scale. Randomeffects
models and inverse variance method were used to meta-analyze the association between
insulin resistance components and EC.
Results: Twenty-five studies satisfied our inclusion criteria. Fasting insulin levels (13 studies,
n Z 4088) were higher in women with EC (mean difference [MD] 33.94 pmol/L, 95% confi-
dence interval [CI] 15.04e52.85, p Z 0.0004). No differences were seen in postmenopausal
versus pre- and postmenopausal subgroup analysis. Similarly, non-fasting/fasting C-peptide
levels (five studies, n Z 1938) were also higher in women with EC (MD 0.14 nmol/L, 95% CI 0.08e0.21, p < 0.00001). Homeostatic model assessment - insulin resistance (HOMA-IR)
values (six studies, n Z 1859) in EC patients were significantly higher than in women without
EC (MD 1.13, 95% CI 0.20e2.06, p Z 0.02). There was moderate-to-high heterogeneity
among the included studies.
Conclusion: Currently available epidemiologic evidence is suggestive of significantly higher
risk of EC in women with high fasting insulin, non-fasting/fasting C-peptide and HOMAIR
values.
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Metanálise para Modelos de Regressão / Meta-analysis for Regression ModelsSantos, Laryssa Vieira dos 28 October 2016 (has links)
A metanálise tem sido amplamente utilizada em estudos médicos especialmente em revisões sistemáticas de ensaios clínicos aleatorizados. Para modelos de regressão a técnica ainda é muito escassa e limitada. Geralmente trata-se apenas de uma medida baseada nas médias de estimativas pontuais dos diferentes estudos, perdendo-se muita informação dos dados originais. Atualmente torna-se cada vez mais fundamental o uso da metanálise para sumarizar estudos de mesmo objetivo, em razão do avanço da ciência e o desejo de usar o menor número de seres humanos em ensaios clínicos. Utilizando uma medida metanalítica Bayesiana, o objetivo é propor um método genérico e eficiente para realizar metanálise em modelos de regressão. / Meta analysis has been widely used in medical studies especially in systematic reviews of randomized clinical trials. For regression models the technique is still very scarce and limited. Usually it is just a measure based on the average point estimates of dierent studies, losing a lot of information of the original data. Currently it becomes increasingly important to use the meta-analysis to summarize the same objective studies, due to the advancement of science and the desire to use the smallest number of human subjects in clinical trials. Using a meta-analytic Bayesian measure, the objective is to propose a generic and ecient method to perform meta-analysis in regression models.
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Efficacy of artemisinin derivatives in treating severe malaria in children: A systematic review and meta-analysisPraygod, George 01 November 2006 (has links)
Student Number : 0416598H -
MSc research report -
School of Public Health -
Faculty of Health Sciences / Background
Evidence shows that the efficacy of intravenous quinine, which is the mainstay for treating severe malaria in children, is decreasing. Artemisinin derivatives are the potential replacement for quinine. Their efficacy compared to quinine in treating severe malaria in children is not well known.
Objective
To assess the efficacy of parenteral artemisinin derivatives versus parenteral quinine in treating severe malaria in children.
Search strategy
The Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 4, 2005), MEDLINE (1966 to October 2005), EMBASE (1980 to October 2005), and LILACS (1982 to October 2005) were searched. Malaria researchers and a pharmaceutical company were contacted. In addition, conference proceedings were also searched.
Selection criteria
Randomised controlled studies comparing parenteral artemisinin derivatives with parenteral quinine in treating severe malaria in children. All trials had to report mortality as an outcome.
Data collection
After data were extracted, two individuals independently assessed the trial quality. In addition, information on adverse effects from the studies was also collected.
Main results
Eleven trials were selected (1455 subjects), nine of them from Africa and the rest from Asia. Allocation concealment was adequate in seven trials (1238 subjects). Overall there was no difference in mortality between artemisinin derivatives and quinine (Risk Ratio= 0.89, 95% confidence interval 0.71 to 1.1). There was no difference in mortality between adequately concealed and inadequately concealed /unconcealed trials (Risk Ratio = 0.93, 95% confidence interval 0.74 to 1.16 and Risk Ratio=0.66, 95% confidence interval 0.36 to 1.22). In Parasite Clearance Time (PCT), though there was no statistical difference between the two groups there was a tendency towards favouring the artemisinin derivatives (weighted mean difference among studies which reported PCT as mean was -4.76 with 95% confidence interval -9.68 to 0.17 and all three studies which reported PCT as median showed that artemisinin derivatives cleared parasites faster than quinine, each had p<0.001). However; when only trials with adequate concealment were considered this potential advantage disappeared. In exploring heterogeneity for PCT, it was shown that study settings (Asia versus Africa) might have been a cause for heterogeneity. The artemisinin derivatives resolved coma faster than quinine (weighted mean difference=-5.32, 95%CI: -8.06 to -2.59), but when only trials with adequate concealment were considered this difference disappeared. Other secondary outcomes i.e. Fever clearance time, Incidence of neurological sequelae, and 28th day cure rate showed no significant difference between artemisinin derivatives and quinine. There was no enough data to make meaningful comparison of adverse effects between the two groups.
Conclusions
The available evidence suggests that parenteral artemisinin derivatives are as efficacious as quinine in preventing mortality from severe malaria in children.
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Efficacy and Safety of Bisphosphonates for Postmenopausal Women: A Systematic Review and Network Meta-analysisZheng, Carine 26 February 2019 (has links)
Fragility fractures caused by loss of bone mass due to postmenopausal osteoporosis represent a growing morbidity worldwide. Bisphosphonates are first-line medications for fracture treatment and prevention. In the first phase, we updated a Cochrane systematic review of randomized controlled trials on alendronate, assessing its efficacy for five types of fracture prevention, quality of life, and various safety outcomes. In the second phase, we combined indirect and direct evidence to perform a network meta-analysis including alendronate and nine other bisphosphonates evaluating the comparative efficacy and safety of these treatments. Overall, 58 studies were included in the review and 83 studies in the network. Most evidence was of moderate to high quality. Alendronate and zoledronic acid were effective for preventing the most types of fractures, while off-label and unapproved bisphosphonates showed poor efficacy. More evidence is required to evaluate long-term treatment and rare adverse events.
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The effectiveness of occupational stress management intervention: a meta-analytic study. / Stress management interventionJanuary 2005 (has links)
Yau Man Yin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 44-57). / Abstract in English and Chinese. / Chapter CHAPTER 1. --- INTRODUCTION --- p.1 / Review on Stress and Coping --- p.1 / Coping --- p.2 / Research on Stress and Coping --- p.3 / Using SMIs to Study Stress and Coping --- p.5 / Occupational Stress --- p.6 / Table 1 --- p.9 / Reasons for Meta-Analysis --- p.10 / Content As a Moderator --- p.11 / Identification of Stressors as a Moderator --- p.12 / Massed Vs Distributed Session as a Moderator --- p.13 / Time Interval as Moderator --- p.15 / Outcomes --- p.16 / Chapter CHAPTER 2. --- METHOD --- p.18 / Literature Search --- p.18 / Inclusion Criteria --- p.18 / Meta-Analysis Procedures --- p.19 / Coding --- p.21 / Publication Bias --- p.21 / Chapter CHAPTER 3. --- RESULTS --- p.22 / Overall --- p.22 / Table 2 --- p.23 / Moderators --- p.24 / Table 3 --- p.24 / Table 4 --- p.26 / Table 5 --- p.26 / Table 6 --- p.27 / Table7 --- p.29 / Table 8 --- p.30 / Table 9 --- p.31 / Chapter CHAPTER 4: --- DISCUSSION --- p.32 / Workshop Content --- p.34 / Identification of Stress --- p.35 / Massed and Distributed Practice --- p.36 / Time interval --- p.37 / Implications --- p.38 / Limitations and Future Directions --- p.40 / Concluding Remarks --- p.42 / REFERENCES --- p.44
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Evaluating the effectiveness of leadership training programs. / Leadership trainingJanuary 2005 (has links)
Au Ka Yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 35-47). / Abstract in English and Chinese. / ABSTRACT --- p.1 / 摘要 --- p.2 / ACKNOWLEDGEMENT --- p.3 / Chapter CHAPTER 1. --- INTRODUCTION --- p.7 / Leadership Competencies --- p.7 / Importance of Leadership Training --- p.8 / Use of Meta-Analysis --- p.9 / Meta-Analysis on Leadership Training --- p.9 / Applying Leadership Theories to Leadership Training --- p.10 / Spacing Effect --- p.12 / Methodological Rigor of Program Design --- p.13 / Hypotheses --- p.16 / Chapter CHAPTER 2. --- METHOD --- p.18 / Literature Search --- p.18 / Inclusion Criteria --- p.18 / Coding Procedure --- p.19 / Meta-Analysis Procedure --- p.20 / Chapter CHAPTER 3. --- RESULTS --- p.22 / Overall Effectiveness --- p.22 / Moderators --- p.24 / Chapter CHAPTER 4. --- DISCUSSION --- p.27 / Discussion on Key Findings --- p.27 / Leadership Training Is Effective in General --- p.27 / Applying Theories Can Enhance the Effectiveness --- p.28 / Spaced Distribution Outperforms Mass Distribution --- p.29 / Characteristics of Measurement May Distort the Effect Size --- p.29 / Theoretical and Practical Implications --- p.31 / Implications for Researchers --- p.31 / Implications for Practitioners --- p.32 / Limitations and Further Studies --- p.33 / What Is Leadership Training Actually? --- p.33 / Meta-Analysis Is Far From Perfect --- p.34 / REFERENCES --- p.35
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Psychological interventions for psychosis : a meta-analysis of social skills training followed by a randomised controlled experimental study assessing the impact of meta-cognitive training addressing the jumping-to-conclusions bias on capacityTurner, David T. January 2017 (has links)
Background There now exist a range of efficacious options for the treatment of psychosis in mental healthcare. The importance of recovery, empowerment, dignity and choice among patients with severe mental health diagnoses are important topics in contemporary research and practice. This thesis presents a meta-analytic review followed by a randomised controlled experimental study. These address distinct but related questions which aim to further our understanding of the choices available for intervention in psychosis and whether intervention may improve the ability of psychosis patients to make those choices. Aims The first objective aimed to offer a comprehensive review of the effectiveness of social skills training (SST), which is a psychological intervention for psychosis. SST has fallen out of favour in the UK and is not widely implemented in practice. We hypothesised that SST would demonstrate superiority for the negative symptoms of psychosis. The second objective was to determine whether decision-making capacity regarding treatment among psychosis patients could be improved by the application of a brief psycho-educational intervention targeting the jumping-to-conclusions (JTC) bias, which is a commonly observed cognitive bias in psychosis. We hypothesised that the intervention would improve decision-making capacity. Methods Firstly, a series of 70 meta-analyses are presented in a systematic review assessing the efficacy of social skills training across a number of psychosis outcome domains: positive symptoms, negative symptoms, general symptoms, overall symptoms and social functioning outcomes. Secondly, a randomised controlled experimental study is presented in which 36 psychosis patients in NHS Lanarkshire and 1 in NHS Dumfries & Galloway were allocated to receive either a brief meta-cognitive training (MCT) intervention or an non-specific control presentation lecture. Capacity was assessed at baseline and post-treatment while the impact of the intervention upon capacity was estimated by ANCOVA. Mediation analyses assessed whether changes in the JTC bias mediated outcome. Findings In the meta-analytic review, SST demonstrated superiority over treatment as usual (TAU. g=0.3), active controls (g=0.2-0.3) and comparators pooled (g=0.2- 0.3) for negative symptoms; and over TAU (g=0.4) and comparators pooled (g=0.3) for general psychopathology. In the randomised controlled study, MCT demonstrated large effects on two capacity outcomes; overall capacity (d=0.96, p < .05) and appreciation (d=0.87, p < .05). Exploratory analyses suggested a mediating effect of JTC (d=0.64, p < .05). Interpretation SST demonstrates a magnitude of effect for negative symptoms similar to those commonly reported for CBT for positive symptoms and may have potential for wider implementation in mental healthcare settings. The randomised controlled study suggests that psycho-educational interventions targeting capacity have clinical utility and may be developed for implementation. Limitations included lack of blinding, no fidelity checks and inclusion based on clinical diagnosis therefore a larger randomised controlled trial addressing these limitations is warranted.
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