46 resultados para Sensitivity and Specificity


Relevância:

100.00% 100.00%

Publicador:

Resumo:

This study compares the effectiveness of Bayesian networks versus Decision Trees in modeling the Integral Theory of Female Urinary Incontinence diagnostic algorithm. Bayesian networks and Decision Trees were developed and trained using data from 58 adult women presenting with urinary incontinence symptoms. A Bayesian Network was developed in collaboration with an expert specialist who regularly utilizes a non-automated diagnostic algorithm in clinical practice. The original Bayesian network was later refined using a more connected approach. Diagnoses determined from all automated approaches were compared with the diagnoses of a single human expert. In most cases, Bayesian networks were found to be at least as accurate as the Decision Tree approach. The refined Connected Bayesian Network was found to be more accurate than the Original Bayesian Network accurately discriminated between diagnoses despite the small sample size. In contrast, the Connected and Decision Tree approaches were less able to discriminate between diagnoses. The Original Bayesian Network was found to provide an excellent basis for graphically communicating the correlation between symptoms and laxity defects in a given anatomical zone. Performance measures in both networks indicate that Bayesian networks could provide a potentially useful tool in the management of female pelvic floor dysfunction. Before the technique can be utilized in practice, well-established learning algorithms should be applied to improve network structure. A larger training data set should also improve network accuracy, sensitivity, and specificity.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Elevated anxiety sensitivity and the tendency to catastrophically misinterpret ambiguous bodily sensations has been demonstrated in people who experience nonclinical levels of panic (Richards, Austin, & Alvarenga, 2001), and anxiety sensitivity has been shown to be associated with insecure attachment in adolescents and young adults (Weems, Berman, Silverman, and Saavedra, 2001). This study investigated the relationship between attachment style, anxiety sensitivity and catastrophic misinterpretation among 11 nonclinical panickers and 58 nonanxious controls aged 18 to 19 years. Participants completed the Brief Bodily Sensations Interpretation Questionnaire (BBSIQ), Anxiety Sensitivity Index (ASI) and an attachment questionnaire. The hypothesis that insecurely attached individuals would demonstrate greater catastrophic misinterpretation and higher anxiety sensitivity than securely attached individuals was not supported; however, nonclinical panickers gave more anxiety-related interpretations of ambiguous internal stimuli than nonanxious controls. Results do not support the notion that attachment style is related to anxiety sensitivity or catastrophic misinterpretation (regardless of panic experience). Results do, however, support the notion that anxiety-related misinterpretation of ambiguous somatic sensations precedes the onset of panic disorder.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This article aims to discover the differences among consumer personality clusters in regard to their extent of fashion consciousness and prestige sensitivity. Data were collected from 251 undergraduate students using self-administered questionnaires. Cluster analysis and MANOVA were employed to assess whether significant differences exist among four personality clusters. The study used the Big Five scale items to measure consumer personality and found that respondents who score low on the “openness to experience” dimension tend to be less prestige sensitive, and those who score high on “extraversion,” “agreeableness,” and “conscientiousness” tend to be highly fashion conscious.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Orthotopic or intracardiac injection of human breast cancer cell lines into immunocompromised mice allows study of the molecular basis of breast cancer metastasis. We have established a quantitative real-time PCR approach to analyze metastatic spread of human breast cancer cells inoculated into nude mice via these routes. We employed MDA-MB-231 human breast cancer cells genetically tagged with a bacterial β-galactosidase (Lac-Z) retroviral vector, enabling their detection by TaqMan® real-time PCR. PCR detection was linear, specific, more sensitive than conventional PCR, and could be used to directly quantitate metastatic burden in bone and soft organs. Attesting to the sensitivity and specificity of the PCR detection strategy, as few as several hundred metastatic MDA-MB-231 cells were detectable in 100 μm segments of paraffin-embedded lung tissue, and only in samples adjacent to sections that scored positive by histological detection. Moreover, the measured real-time PCR metastatic burden in the bone environment (mouse hind-limbs, n=48) displayed a high correlation to the degree of osteolytic damage observed by high resolution X-ray analysis (r 2=0.972). Such a direct linear relationship to tumor burden and bone damage substantiates the so-called `vicious cycle' hypothesis in which metastatic tumor cells promote the release of factors from the bone which continue to stimulate the tumor cells. The technique provides a useful tool for molecular and cellular analysis of human breast cancer metastasis to bone and soft organs, can easily be extended to other cell/marker/organ systems, and should also find application in preclinical assessment of anti-metastatic modalities.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The activation of the sympathetic nervous system through the central actions of the adipokine leptin has been suggested as a major mechanism by which obesity contributes to the development of hypertension. However, direct evidence for elevated sympathetic activity in obesity has been limited to muscle. The present study examined the renal sympathetic nerve activity and cardiovascular effects of a high-fat diet (HFD), as well as the changes in the sensitivity to intracerebroventricular leptin. New Zealand white rabbits fed a 13.5% HFD for 4 weeks showed modest weight gain but a 2- to 3-fold greater accumulation of visceral fat compared with control rabbits. Mean arterial pressure, heart rate, and plasma norepinephrine concentration increased by 8%, 26%, and 87%, respectively (P<0.05), after 3 weeks of HFD. Renal sympathetic nerve activity was 48% higher (P<0.05) in HFD compared with control diet rabbits and was correlated to plasma leptin (r=0.87; P<0.01). Intracerebroventricular leptin administration (5 to 100 μg) increased mean arterial pressure similarly in both groups, but renal sympathetic nerve activity increased more in HFD-fed rabbits. By contrast, intracerebroventricular leptin produced less neurons expressing c-Fos in HFD compared with control rabbits in regions important for appetite and sympathetic actions of leptin (arcuate: −54%, paraventricular: −69%, and dorsomedial hypothalamus: −65%). These results suggest that visceral fat accumulation through consumption of a HFD leads to marked sympathetic activation, which is related to increased responsiveness to central sympathoexcitatory effects of leptin. The paradoxical reduction in hypothalamic neuronal activation by leptin suggests a marked “selective leptin resistance” in these animals.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Lisa investigated the taste of fat and its influence on excess fat consumption and obesity. This research established that taste sensitivity to fat can be modulated by fat intake and may be used as an obesity prevention tool in the future.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This study aimed to (1) determine preliminary validity of the Developmental Behaviour Checklist-Hyperactivity Index (DBC-HI) as a screening measure of combined-type ADHD in autism and ADHD, and (2) compare emotional-behavioural disturbance using the DBC in autism, ADHD and autism + ADHD. Forty-nine age- and PIQ-matched young people [6-18 years; 12 autism, 13 ADHD, 12 autism + ADHD, 12 typically developing] were recruited. Parents completed the Conners-Revised Rating Scale and DBC. The DBC-HI displayed strong internal consistency and good external validity, reliably measuring combined-type ADHD. The DBC-HI distinguished autism from autism + ADHD with fair sensitivity and specificity. Individuals with autism + ADHD exhibited a more severe profile of emotional-behavioural disturbance than autism or ADHD alone. The DBC may be a useful 'all-in-one' screening tool to (1) identify comorbidity and (2) determine the severity of emotional-behavioural disturbance in autism and/or ADHD. © 2014 Elsevier Ltd.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objectives: To examine whether combined vitamin D and calcium supplementation improves insulin sensitivity, insulin secretion, β-cell function, inflammation and metabolic markers.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

To develop a mathematical model to predict the probability of having community-acquired pneumonia and to evaluate an already developed prediction rule that has not been validated in a clinical scenario.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The successful use of a targeted therapy is intrinsically linked to the ability of a companion diagnostic to correctly identify patients most likely to benefit from treatment. The aim of this study was to review the characteristics of companion diagnostics that are of importance for inclusion in an economic evaluation. Approaches for including these characteristics in model-based economic evaluations are compared with the intent to describe best practice methods. Five databases and government agency websites were searched to identify model-based economic evaluations comparing a companion diagnostic and subsequent treatment strategy to another alternative treatment strategy with model parameters for the sensitivity and specificity of the companion diagnostic (primary synthesis). Economic evaluations that limited model parameters for the companion diagnostic to only its cost were also identified (secondary synthesis). Quality was assessed using the Quality of Health Economic Studies instrument. 30 studies were included in the review (primary synthesis n = 12; secondary synthesis n = 18). Incremental cost-effectiveness ratios may be lower when the only parameter for the companion diagnostic included in a model is the cost of testing. Incorporating the test's accuracy in addition to its cost may be a more appropriate methodological approach. Altering the prevalence of the genetic biomarker, specific population tested, type of test, test accuracy and timing/sequence of multiple tests can all impact overall model results. The impact of altering a test's threshold for positivity is unknown as it was not addressed in any of the included studies. Additional quality criteria as outlined in our methodological checklist should be considered due to the shortcomings of standard quality assessment tools in differentiating studies that incorporate important test-related characteristics and those that do not. There is a need to refine methods for incorporating the characteristics of companion diagnostics into model-based economic evaluations to ensure consistent and transparent reimbursement decisions are made.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Abstract Aims: To develop and evaluate a screening tool to identify people with diabetes at increased risk of medication problems relating to hypoglycaemia and medication non-adherence. Methods: A retrospective audit of attendances at a diabetes outpatient clinic at a public, teaching hospital over a 16-month period was conducted. Logistic regression was undertaken to examine risk factors associated with medication problems relating to hypoglycaemia and medication non-adherence and the most predictive set of factors comprise the Diabetes Medication Risk Screening Tool. Evaluating the tool involved assessing sensitivity and specificity, positive and negative predictive values, cut-off scores, inter-rater reliability, and content validity. Results: The Diabetes Medication Risk Screening Tool comprises seven predictive factors: age, living alone, English language, mental and behavioural problems, comorbidity index score, number of medications prescribed, and number of high-risk medications prescribed. The tool has 76.5% sensitivity, 59.5% specificity, and has a 65.1% positive predictive value, and a 71.8% negative predictive value. A score of 27 or more out of 62 was associated with high-risk of a medication problem. The inter-rater reliability of the tool was high (κ = 0.79, 95% CI 0.75 - 0.84) and the content validity index was 99.4%. Conclusion: The Diabetes Medication Risk Screening Tool has good psychometric properties and can proactively identify people with diabetes at greatest risk of medication problems relating to hypoglycaemia and medication non-adherence.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

© 2015 Australian Psychological Society. Objective: Sensory-processing sensitivity refers to a trait-like difference in the extent to which individuals strongly and deeply process a variety of stimuli in the environment. While being highly sensitive has been linked to increased experiences of distress, the reasons for this are not well known. One potential mediator of this effect is emotional regulation-the set of processes influencing which emotions we have, when we have them, and how we experience and express them. This study therefore aimed to investigate whether sensory processing sensitivity is linked to negative affect via emotional regulation processes. Method: N=157 participants (n=118 females) completed online questionnaires assessing negative affect, sensory-processing sensitivity, along with two multidimensional emotional regulation measures. Results: An individual's lack of access to emotional regulation strategies, greater awareness of emotion, and lack of acceptance towards feeling distressed, acted as partial mediators between sensory-processing sensitivity and symptoms of depression. Combinations of these variables also partially mediated the relationship between sensory-processing sensitivity and symptoms of anxiety and stress. Conclusions: It is suggested that repeatedly experiencing aversive sensory-states among those with increased sensory-processing sensitivity impacts on their general awareness and acceptance of internal states and the confidence that one can regulate them. This in turn leads to the experience of negative affective states. Limitations of the present study and implications for therapeutic interventions are discussed.