410 resultados para Test reliability
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The bentiromide test was evaluated using plasma p-aminobenzoic acid as an indirect test of pancreatic insufficiency in young children between 2 months and 4 years of age. To determine the optimal test method, the following were examined: (a) the best dose of bentiromide (15 mg/kg or 30 mg/kg); (b) the optimal sampling time for plasma p-aminobenzoic acid, and; (c) the effect of coadministration of a liquid meal. Sixty-nine children (1.6 ± 1.0 years) were studied, including 34 controls with normal fat absorption and 35 patients (34 with cystic fibrosis) with fat maldigestion due to pancreatic insufficiency. Control and pancreatic insufficient subjects were studied in three age-matched groups: (a) low-dose bentiromide (15 mg/kg) with clear fluids; (b) high-dose bentiromide (30 mg/kg) with clear fluids, and; (c) high-dose bentiromide with a liquid meal. Plasma p-aminobenzoic acid was determined at 0, 30, 60, and 90 minutes then hourly for 6 hours. The dose effect of bentiromide with clear liquids was evaluated. High-dose bentiromide best discriminated control and pancreatic insufficient subjects, due to a higher peak plasma p-aminobenzoic acid level in controls, but poor sensitivity and specificity remained. High-dose bentiromide with a liquid meal produced a delayed increase in plasma p-aminobenzoic acid in the control subjects probably caused by retarded gastric emptying. However, in the pancreatic insufficient subjects, use of a liquid meal resulted in significantly lower plasma p-aminobenzoic acid levels at all time points; plasma p-aminobenzoic acid at 2 and 3 hours completely discriminated between control and pancreatic insufficient patients. Evaluation of the data by area under the time-concentration curve failed to improve test results. In conclusion, the bentiromide test is a simple, clinically useful means of detecting pancreatic insufficiency in young children, but a higher dose administered with a liquid meal is recommended.
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Global citizenship has emerged as a pressing curricular priority which all educational systems are currently grappling with. The challenge is to negotiate how this orientation might sit alongside the more traditional mission of mass school curriculum in building collective ballast for a national identity through a common morality and shared narratives, or may conflict with efforts to protect and promote indigenous and minority identities. As a case study of how these agendas interact, this chapter will consider curricular responses to global imperatives in the variegated conditions across the Australasian region (defined as Australia, New Zealand and Papua New Guinea). The chapter will outline recent developments in the social, economic and political contexts surrounding curricular reforms in these settings, and demonstrate how these developments have changed the conditions of possibility and strength of purpose behind efforts to internationalise school curricula. Three types of systemic responses are then described: firstly, an appetite for globally branded curricula such as the International Baccalaureate, Montessori, and Cambridge University Certificates to distinguish some in a stratified market; secondly, convergence in curriculum to improve national performance on international standardised tests; and thirdly, the infusion of cosmopolitan sensibilities, regional identities and intercultural competencies as a core curricular goal for all. The chapter considers the various pragmatic interpretations of ‘internationalisation’ in these responses, and argues that the third response seems both the most difficult to enact, and the most vulnerable to political interference.
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The aim of this study was to asses results obtained from a range of commonly performed lower extremity “open and closed” chain kinetic tests used for predicting foot function and correlate these test findings to data obtained from the Zebris WinFDM-T system®. When performed correctly these tests are thought to be indicators of lower extremity function. Podiatrists frequently perform examinations of joint and muscle structures to understand biomechanical function; however the relationship between these routine tests and forces generated during the gait cycle are not always well understood. This can introduce a degree of variability in clinical interpretation which creates conjecture regarding the value of these tests.
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Traffic incidents are recognised as one of the key sources of non-recurrent congestion that often leads to reduction in travel time reliability (TTR), a key metric of roadway performance. A method is proposed here to quantify the impacts of traffic incidents on TTR on freeways. The method uses historical data to establish recurrent speed profiles and identifies non-recurrent congestion based on their negative impacts on speeds. The locations and times of incidents are used to identify incidents among non-recurrent congestion events. Buffer time is employed to measure TTR. Extra buffer time is defined as the extra delay caused by traffic incidents. This reliability measure indicates how much extra travel time is required by travellers to arrive at their destination on time with 95% certainty in the case of an incident, over and above the travel time that would have been required under recurrent conditions. An extra buffer time index (EBTI) is defined as the ratio of extra buffer time to recurrent travel time, with zero being the best case (no delay). A Tobit model is used to identify and quantify factors that affect EBTI using a selected freeway segment in the Southeast Queensland, Australia network. Both fixed and random parameter Tobit specifications are tested. The estimation results reveal that models with random parameters offer a superior statistical fit for all types of incidents, suggesting the presence of unobserved heterogeneity across segments. What factors influence EBTI depends on the type of incident. In addition, changes in TTR as a result of traffic incidents are related to the characteristics of the incidents (multiple vehicles involved, incident duration, major incidents, etc.) and traffic characteristics.
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Mastery motivation is an important developmental construct that has implications for development across the lifespan. Research to date has focused predominantly on infants and children, with the Dimensions of Mastery Questionnaire (DMQ) being the most widely used measure of mastery motivation. This paper reports on the development and initial validation of an adult measure: the Dimensions of Adult Mastery Motivation Questionnaire (DAMMQ). Six hundred and twenty-eight adults (68 % female) aged 18 to 90 years completed the questionnaire. Factor analysis produced 24 items that represented five factors: task persistence, preference for challenge, task related pleasure, task absorption and competence/self-efficacy. The DAMMQ was found to have good internal consistency, test-retest reliability and concurrent validity. Within group differences for age, gender and education are reported. The development of the DAMMQ paves the way for future research about mastery motivation in adult populations.
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Objective: To describe patient participation and clinical performance in a colorectal cancer (CRC) screening program utilising faecal occult blood test (FOBT). Methods: A community-based intervention was conducted in a small, rural community in north Queensland, 2000/01. One of two FOBT kits – guaiac (Hemoccult-ll) or immunochemical (Inform) – was assigned by general practice and mailed to participants (3,358 patients aged 50–74 years listed with the local practices). Results: Overall participation in FOBT screening was 36.3%. Participation was higher with the immunochemical kit than the guaiac kit (OR=1.9, 95% Cl 1.6-2.2). Women were more likely to comply with testing than men (OR=1.4, 95% Cl 1.2-1.7), and people in their 60s were less likely to participate than those 70–74 years (OR=0.8, 95% Cl 0.6-0.9). The positivity rate was higher for the immunochemical (9.5%) than the guaiac (3.9%) test (χ2=9.2, p=0.002), with positive predictive values for cancer or adenoma of advanced pathology of 37.8% (95% Cl 28.1–48.6) for !nform and 40.0% (95% Cl 16.8–68.7) for Hemoccult-ll. Colonoscopy follow-up was 94.8% with a medical complication rate of 2–3%. Conclusions: An immunochemical FOBT enhanced participation. Higher positivity rates for this kit did not translate into higher false-positive rates, and both test types resulted in a high yield of neoplasia. Implications: In addition to type of FOBT, the ultimate success of a population-based screening program for CRC using FOBT will depend on appropriate education of health professionals and the public as well as significant investment in medical infrastructure for colonoscopy follow-up.
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We have derived a versatile gene-based test for genome-wide association studies (GWAS). Our approach, called VEGAS (versatile gene-based association study), is applicable to all GWAS designs, including family-based GWAS, meta-analyses of GWAS on the basis of summary data, and DNA-pooling-based GWAS, where existing approaches based on permutation are not possible, as well as singleton data, where they are. The test incorporates information from a full set of markers (or a defined subset) within a gene and accounts for linkage disequilibrium between markers by using simulations from the multivariate normal distribution. We show that for an association study using singletons, our approach produces results equivalent to those obtained via permutation in a fraction of the computation time. We demonstrate proof-of-principle by using the gene-based test to replicate several genes known to be associated on the basis of results from a family-based GWAS for height in 11,536 individuals and a DNA-pooling-based GWAS for melanoma in approximately 1300 cases and controls. Our method has the potential to identify novel associated genes; provide a basis for selecting SNPs for replication; and be directly used in network (pathway) approaches that require per-gene association test statistics. We have implemented the approach in both an easy-to-use web interface, which only requires the uploading of markers with their association p-values, and a separate downloadable application.
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The impact of erroneous genotypes having passed standard quality control (QC) can be severe in genome-wide association studies, genotype imputation, and estimation of heritability and prediction of genetic risk based on single nucleotide polymorphisms (SNP). To detect such genotyping errors, a simple two-locus QC method, based on the difference in test statistic of association between single SNPs and pairs of SNPs, was developed and applied. The proposed approach could detect many problematic SNPs with statistical significance even when standard single SNP QC analyses fail to detect them in real data. Depending on the data set used, the number of erroneous SNPs that were not filtered out by standard single SNP QC but detected by the proposed approach varied from a few hundred to thousands. Using simulated data, it was shown that the proposed method was powerful and performed better than other tested existing methods. The power of the proposed approach to detect erroneous genotypes was approximately 80% for a 3% error rate per SNP. This novel QC approach is easy to implement and computationally efficient, and can lead to a better quality of genotypes for subsequent genotype-phenotype investigations.
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Background: Fatigue is one of the most distressing and commonly experienced symptoms in patients with advanced cancer. Although the self-management (SM) of cancer-related symptoms has received increasing attention, no research instrument assessing fatigue SM outcomes for patients with advanced cancer is available. Objectives: to describe the development and preliminary testing of an interviewer administered instrument for assessing the frequency, and perceived levels of effectiveness and self-efficacy associated with fatigue SM behaviors in patients with advanced cancer. Methods: The development and testing of the Self-efficacy in Managing Symptoms Scale- Fatigue Subscale for Patients with Advanced Cancer (SMSFS-A) involved a number of procedures: item-generation using a comprehensive literature review and semi-structured interviews, content validity evaluation using expert panel reviews, and face validity and test-retest reliability evaluation using pilot testing. Results: Initially, 23 items (22 specific behaviors with one global item) were generated from the literature review and semi-structured interviews. After two rounds of expert panel review, the final scale was reduced to 17 items (16 behaviors with one global item). Participants in the pilot test (n=10) confirmed that the questions in this scale were clear and easy to understand. Bland-Altman analysis showed agreement of results over a one-week interval. Conclusions: The SMSFS-A items were generated using multiple sources. This tool demonstrated preliminary validity and reliability. Implications for practice: The SMSFS-A has the potential to be used for clinical and research purposes. Nurses can use this instrument for collecting data to inform the initiation of appropriate fatigue SM support for this population.
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This paper reports a rare investigation of stopover destination image. Although the topic of destination image has been one of the most popular in the tourism literature since the 1970s, there has been a lack of research attention in relation to the context of stopover destinations for long haul international travellers. The purpose of this study was to identify attributes deemed salient to Australian consumers when considering stopover destinations for long haul travel to the United Kingdom and Europe. Underpinned by Personal Construct Theory (PCT), the study used the Repertory Test to identify 21 salient attributes, which could be used in the development of a survey instrument to measure the attractiveness of a competitive set of stopover destinations. While the list of attributes shared some commonality with general studies of destination image reported in the literature, the elicitation of a relatively large number of stopover context specific attributes highlights the potential benefit of engaging with consumers in qualitative research, such as using the Repertory Test, during the questionnaire development stage.
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BACKGROUND Physical therapy for youth with cerebral palsy (CP) who are ambulatory includes interventions to increase functional mobility and participation in physical activity (PA). Thus, reliable and valid measures are needed to document PA in youth with CP. OBJECTIVE The purpose of this study was to evaluate the inter-instrument reliability and concurrent validity of 3 accelerometer-based motion sensors with indirect calorimetry as the criterion for measuring PA intensity in youth with CP. METHODS Fifty-seven youth with CP (mean age=12.5 years, SD=3.3; 51% female; 49.1% with spastic hemiplegia) participated. Inclusion criteria were: aged 6 to 20 years, ambulatory, Gross Motor Function Classification System (GMFCS) levels I through III, able to follow directions, and able to complete the full PA protocol. Protocol activities included standardized activity trials with increasing PA intensity (resting, writing, household chores, active video games, and walking at 3 self-selected speeds), as measured by weight-relative oxygen uptake (in mL/kg/min). During each trial, participants wore bilateral accelerometers on the upper arms, waist/hip, and ankle and a portable indirect calorimeter. Intraclass coefficient correlations (ICCs) were calculated to evaluate inter-instrument reliability (left-to-right accelerometer placement). Spearman correlations were used to examine concurrent validity between accelerometer output (activity and step counts) and indirect calorimetry. Friedman analyses of variance with post hoc pair-wise analyses were conducted to examine the validity of accelerometers to discriminate PA intensity across activity trials. RESULTS All accelerometers exhibited excellent inter-instrument reliability (ICC=.94-.99) and good concurrent validity (rho=.70-.85). All accelerometers discriminated PA intensity across most activity trials. LIMITATIONS This PA protocol consisted of controlled activity trials. CONCLUSIONS Accelerometers provide valid and reliable measures of PA intensity among youth with CP.
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A central tenet in the theory of reliability modelling is the quantification of the probability of asset failure. In general, reliability depends on asset age and the maintenance policy applied. Usually, failure and maintenance times are the primary inputs to reliability models. However, for many organisations, different aspects of these data are often recorded in different databases (e.g. work order notifications, event logs, condition monitoring data, and process control data). These recorded data cannot be interpreted individually, since they typically do not have all the information necessary to ascertain failure and preventive maintenance times. This paper presents a methodology for the extraction of failure and preventive maintenance times using commonly-available, real-world data sources. A text-mining approach is employed to extract keywords indicative of the source of the maintenance event. Using these keywords, a Naïve Bayes classifier is then applied to attribute each machine stoppage to one of two classes: failure or preventive. The accuracy of the algorithm is assessed and the classified failure time data are then presented. The applicability of the methodology is demonstrated on a maintenance data set from an Australian electricity company.
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Multimetric ecological condition assessment has become an important biodiversity management tool. This study was the first to examine the reliability of these ecological surrogates across variable environments, and the implications for surrogate efficacy. It was demonstrated that through strategic application and design of the multimetric ecological condition index, the effects of environmental gradients and disturbance regimes can be mitigated, and that ecological condition assessment may serve as a scientifically rigorous approach for conservation planning.
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Overview This report, published in conjunction with a summary overview of results of rounds 1–6, is the sixth in a series of laboratory-based evaluations of rapid diagnostic tests (RDTs) for malaria. It provides a comparative measure of their performance in a standardized way to distinguish between well and poorly performing tests. It can be used by malaria control programmes and guide WHO procurement recommendations for these diagnostic tools. The evaluation reported here was a joint project of the WHO Global Malaria Programme, the Foundation for Innovative New Diagnostics (FIND) and the United States Centers for Disease Control and Prevention (CDC) within the WHO-FIND Malaria RDT Evaluation Programme. The project was financed by FIND through a grant from UNITAID.
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The test drive is a well-known step in car buying. In the emerging plug-in electric vehicle (PEV) market, however, the influence of a pre-purchase test drive on a consumer's inclination to purchase is unknown. Policy makers and industry participants both are eager to understand what factors motivate vehicle consumers at the point-of-sale. A number of researchers have used choice models to shed light on consumer perceptions of PEVs, and others have investigated consumer change in disposition toward a PEV over the course of a trial, wherein test driving a PEV may take place over a number of consecutive days, weeks or months. However, there is little written on the impact of a short-term test drive - a typical experience at dealerships or public "ride-and-drive" events. The impact of a typical test drive, often measured in minutes of driving, is not well understood. This paper first presents a synthesis of the literature on the effect of PEV test drives as they relate to consumer disposition toward PEVs. An analysis of data obtained from an Australian case study whereby attitudinal and stated preference data were collected pre- and post- test drive at public "ride-and-drive" event held Brisbane, Queensland in March 2014 using a custom-designed iPad application. Motorists' perceptions and choice preferences around PEVs were captured, revealing the relative importance of their experience behind the wheel. Using the Australian context as a case-study, this paper presents an exploratory study of consumers' stated preferences toward PEVs both before and after a short test drive.