Use of fine needle aspirate from peripheral nerves of pure-neural leprosy for cytology and PCR to confirm the diagnosis: a pilot study.

PubMed

Reja, Abu Hena Hasanoor; De, Abhishek; Biswas, Supratik; Chattopadhyay, Amitabha; Chatterjee, Gobinda; Bhattacharya, Basudev; Sarda, Aarti; Aggarwal, Ishad

2013-01-01

The diagnosis of pure neural leprosy (PNL) remained subjective because of over-dependence of clinical expertise and a lack of simple yet reliable diagnostic tool. The criteria for diagnosis, proposed by Jardim et al., are not routinely done by clinicians in developing country as it involves invasive nerve biopsy and sophisticated anti-PGL-1 detection. We conducted a study using fine needle aspiration cytology (FNAC) coupled with Ziehl Neelsen staining (ZN staining) and Multiplex-Polymerase Chain Reaction (PCR) specific for M. leprae for an objective diagnosis of pure neural leprosy (PNL), which may be simpler and yet reliable. The aim of the study is to couple FNAC with ZN staining and multiplex PCR to diagnose pure neural leprosy patients rapidly, in simpler and yet reliable way. Thirteen patients of PNL as diagnosed by two independent consultants were included as case, and 5 patients other than PNL were taken as control in the study. Fine needle aspiration was done on the affected nerve, and aspirates were evaluated for cytology, ZN staining and multiplex-PCR. Out of the 13 cases where fine needle aspiration was done, M. leprae could be elicited in the nerve tissue aspirates in 5 cases (38.4%) with the help of conventional acid-fast staining and 11 cases (84.6%) with the help of multiplex PCR. On cytological examination of the aspirates, only 3 (23%) cases showed specific epithelioid cells, whereas 8 (61.5%) cases showed non-specific inflammation, and 2 (15.3%) cases had no inflammatory cells. Our study demonstrates that in the field of laboratory diagnosis of PNL cases, FNAC in combination with ZN staining for acid-fast bacilli (AFB) and Multiplex-PCR can provide a rapid and definitive diagnosis for the majority of PNL cases. FNAC is a less-invasive, outdoor-based and simpler technique than invasive nerve biopsy procedure. Thus, this study may enlighten the future path for easy and reliable diagnosis of PNL.

Towards early software reliability prediction for computer forensic tools (case study).

PubMed

Abu Talib, Manar

2016-01-01

Versatility, flexibility and robustness are essential requirements for software forensic tools. Researchers and practitioners need to put more effort into assessing this type of tool. A Markov model is a robust means for analyzing and anticipating the functioning of an advanced component based system. It is used, for instance, to analyze the reliability of the state machines of real time reactive systems. This research extends the architecture-based software reliability prediction model for computer forensic tools, which is based on Markov chains and COSMIC-FFP. Basically, every part of the computer forensic tool is linked to a discrete time Markov chain. If this can be done, then a probabilistic analysis by Markov chains can be performed to analyze the reliability of the components and of the whole tool. The purposes of the proposed reliability assessment method are to evaluate the tool's reliability in the early phases of its development, to improve the reliability assessment process for large computer forensic tools over time, and to compare alternative tool designs. The reliability analysis can assist designers in choosing the most reliable topology for the components, which can maximize the reliability of the tool and meet the expected reliability level specified by the end-user. The approach of assessing component-based tool reliability in the COSMIC-FFP context is illustrated with the Forensic Toolkit Imager case study.

Assessment of Reliable Change Using 95% Credible Intervals for the Differences in Proportions: A Statistical Analysis for Case-Study Methodology.

PubMed

Unicomb, Rachael; Colyvas, Kim; Harrison, Elisabeth; Hewat, Sally

2015-06-01

Case-study methodology studying change is often used in the field of speech-language pathology, but it can be criticized for not being statistically robust. Yet with the heterogeneous nature of many communication disorders, case studies allow clinicians and researchers to closely observe and report on change. Such information is valuable and can further inform large-scale experimental designs. In this research note, a statistical analysis for case-study data is outlined that employs a modification to the Reliable Change Index (Jacobson & Truax, 1991). The relationship between reliable change and clinical significance is discussed. Example data are used to guide the reader through the use and application of this analysis. A method of analysis is detailed that is suitable for assessing change in measures with binary categorical outcomes. The analysis is illustrated using data from one individual, measured before and after treatment for stuttering. The application of this approach to assess change in categorical, binary data has potential application in speech-language pathology. It enables clinicians and researchers to analyze results from case studies for their statistical and clinical significance. This new method addresses a gap in the research design literature, that is, the lack of analysis methods for noncontinuous data (such as counts, rates, proportions of events) that may be used in case-study designs.

Concordance of occupational and environmental exposure information elicited from patients with Alzheimer's disease and surrogate respondents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chong, J.P.; Turpie, I.; Haines, T.

Identification of risk factors for Alzheimer's disease through the use of well designed case-control studies has been described as a research priority. Increasing recognition of the neurotoxic potential of many industrial chemicals such as organic solvents raises the question of the occupational and environmental contribution to the etiology of this high-priority health problem. The intention of this study was to develop and evaluate a methodology that could be used in a large scale case-control study of the occupational and environmental risk factors for dementia or a population-based surveillance system for neurotoxic disorders. The specific objectives of this study were tomore » investigate: (1) the reliability of exposure-eliciting, interviewer-administered questionnaires given to patients with Alzheimer's disease (SDAT); (2) the reliability of exposure-eliciting interviewer-administered questionnaires given to the family of patients with SDAT and the agreement with the responses of the patient or surrogate respondents; (3) the reliability and agreement of responses of age- and sex-matched control patients and their families selected from geriatric care institutions and the community, with respect to the same exposure-eliciting and interviewer-administered questionnaire; and (4) the reliability of agent-based exposure ascertainment by a single, trained rater. The results of the study demonstrate that occupational and environmental histories from which exposure information can be derived is most reliably elicited from job descriptions of cases and control subjects rather than job titles alone or detailed probes for potential neurotoxic exposures. This will necessitate the use of standardized interviewer-administered instruments to derive this information in case-control studies of Alzheimer's disease or population-based surveillance systems for occupational and environmental neurotoxicity.« less

Interrater reliability of Violence Risk Appraisal Guide scores provided in Canadian criminal proceedings.

PubMed

Edens, John F; Penson, Brittany N; Ruchensky, Jared R; Cox, Jennifer; Smith, Shannon Toney

2016-12-01

Published research suggests that most violence risk assessment tools have relatively high levels of interrater reliability, but recent evidence of inconsistent scores among forensic examiners in adversarial settings raises concerns about the "field reliability" of such measures. This study specifically examined the reliability of Violence Risk Appraisal Guide (VRAG) scores in Canadian criminal cases identified in the legal database, LexisNexis. Over 250 reported cases were located that made mention of the VRAG, with 42 of these cases containing 2 or more scores that could be submitted to interrater reliability analyses. Overall, scores were skewed toward higher risk categories. The intraclass correlation (ICCA1) was .66, with pairs of forensic examiners placing defendants into the same VRAG risk "bin" in 68% of the cases. For categorical risk statements (i.e., low, moderate, high), examiners provided converging assessment results in most instances (86%). In terms of potential predictors of rater disagreement, there was no evidence for adversarial allegiance in our sample. Rater disagreement in the scoring of 1 VRAG item (Psychopathy Checklist-Revised; Hare, 2003), however, strongly predicted rater disagreement in the scoring of the VRAG (r = .58). (PsycINFO Database Record (c) 2016 APA, all rights reserved).

The Assignment of American Society of Anesthesiologists Physical Status Classification for Adult Polytrauma Patients: Results From a Survey and Future Considerations.

PubMed

Kuza, Catherine M; Hatzakis, George; Nahmias, Jeffry T

2017-12-01

The American Society of Anesthesiologists (ASA) physical status (PS) classification system assesses the preoperative health of patients. Previous studies demonstrated poor interrater reliability and variable ASA PS scores, especially in trauma scenarios. There are few studies that evaluated the assignment of ASA PS scores in trauma patients and no studies that evaluated ASA PS assignment in severely injured adult polytrauma patients. Our objective was to assess interrater reliability and identify sources of discrepancy among anesthesiologists and trauma surgeons in designating ASA PS scores to adult polytrauma patients. A link to an online survey containing questions assessing attitudes regarding ASA PS classification, demographic information, and 8 fictional trauma cases was e-mailed to anesthesiologists and trauma surgeons. The participants were asked to assign an ASA PS score to each scenario and explain their choice. Rater-versus-reference and interrater reliability, beyond that expected by chance, among respondents was analyzed using the Fleiss kappa analysis. A total of 349 participants completed the survey. All 8 cases had inconsistent ASA PS scores; several cases had scores ranging from I to VI and variable emergency (E) designations. Using weighted kappa (Kw) analysis for a subset of 201 respondents (101 trauma surgeons [S] and 100 anesthesiologists [A]), we found moderate (Kw = 0.63; SE = 0.024; 95% confidence interval, 0.594-0.666; P < .001) interrater-versus-reference reliability. The interrater reliability was fair (Kw = 0.43; SE = 0.037; 95% confidence interval, 0.360-0.491; P < .001). This study demonstrates fair interrater reliability beyond that expected by chance of the ASA PS scores among anesthesiologists and trauma surgeons when assessing adult polytrauma patients. Although the ASA PS is used in some trauma risk stratification models, discrepancies of ASA PS scores assigned to trauma cases exist. Future modifications of the ASA PS guidelines should aim to improve the interrater reliability of ASA PS scores in trauma patients. Further studies are warranted to determine the value of the ASA PS score as a trauma prognostic metric.

E-Service Quality Evaluation on E-Government Website: Case Study BPJS Kesehatan Indonesia

NASA Astrophysics Data System (ADS)

Rasyid, A.; Alfina, I.

2017-01-01

This research intends to develop a model to evaluate the quality of e-services on e-government. The proposed model consists of seven dimensions: web design, reliability, responsiveness, privacy and security, personalization, information, and ease of use. The model is used to measure the quality of the e-registration of BPJS Kesehatan, an Indonesian government health insurance program. The validation and reliability testing show that of the seven dimensions proposed, only four that suitable for the case study. The result shows that the BPJS Kesehatan e-registration service is good in reliability and responsiveness dimensions, while from web design and ease of use dimensions the e-service still needs to be optimized.

Estimating aggregate regional user on-time reliability benefit from pre-trip ATIS : Seattle case study

DOT National Transportation Integrated Search

2003-12-01

This study explores the on-time reliability benefits to potential users of a personalized advanced traveler information system (ATIS) providing real-time pre-trip roadway information for the Seattle morning peak period through the application of Heur...

25-hydroxyvitamin D and breast cancer, colorectal cancer, and colorectal adenomas: case-control versus nested case-control studies.

PubMed

Grant, William B

2015-02-01

Existing literature includes concerns regarding reliability of case-control studies of breast cancer incidence with respect to 25-hydroxyvitamin D (25(OH)D) concentrations. For breast cancer, only case-control studies consistently find inverse correlations between 25(OH)D and breast cancer. However, for colorectal cancer, nested case-control studies find significant inverse correlations with respect to 25(OH)D concentrations at baseline for mean follow-up times of 7 years. This is a review of results currently existing in literature. I provide evidence that 25(OH)D concentration values are only useful for short follow-up times for breast cancer since it develops rapidly. To support the robust nature of breast cancer case-control studies, I show that results from 11 studies from seven countries align in a robust power-law fit to the odds ratio versus mean 25(OH)D concentrations. Case-control studies of breast cancer incidence rates provide reliable results. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Understanding Schools as High-Reliability Organizations: An Exploratory Examination of Teachers' and School Leaders' Perceptions of Success

ERIC Educational Resources Information Center

Lorton, Juli A.; Bellamy, G. Thomas; Reece, Anne; Carlson, Jill

2013-01-01

Drawing on research on high-reliability organizations, this interviewbased qualitative case study employs four characteristics of such organizations as a lens for analyzing the operations of one very successful K-5 public school. Results suggest that the school had processes similar to those characteristic of high-reliability organizations: a…

Evaluation of the efficiency and reliability of software generated by code generators

NASA Technical Reports Server (NTRS)

Schreur, Barbara

1994-01-01

There are numerous studies which show that CASE Tools greatly facilitate software development. As a result of these advantages, an increasing amount of software development is done with CASE Tools. As more software engineers become proficient with these tools, their experience and feedback lead to further development with the tools themselves. What has not been widely studied, however, is the reliability and efficiency of the actual code produced by the CASE Tools. This investigation considered these matters. Three segments of code generated by MATRIXx, one of many commercially available CASE Tools, were chosen for analysis: ETOFLIGHT, a portion of the Earth to Orbit Flight software, and ECLSS and PFMC, modules for Environmental Control and Life Support System and Pump Fan Motor Control, respectively.

Complexity, Representation and Practice: Case Study as Method and Methodology

ERIC Educational Resources Information Center

Miles, Rebecca

2015-01-01

While case study is considered a common approach to examining specific and particular examples in research disciplines such as law, medicine and psychology, in the social sciences case study is often treated as a lesser, flawed or undemanding methodology which is less valid, reliable or theoretically rigorous than other methodologies. Building on…

Reliability and Prevalence of an Atypical Development of Phonological Skills in French-Speaking Dyslexics

ERIC Educational Resources Information Center

Sprenger-Charolles, Liliane; Cole, Pascale; Kipffer-Piquard, Agnes; Pinton, Florence; Billard, Catherine

2009-01-01

In the present study, conducted with French-speaking children, we examined the reliability (group study) and the prevalence (multiple-case study) of dyslexics' phonological deficits in reading and reading-related skills in comparison with Reading Level (RL) controls. All dyslexics with no comorbidity problem schooled in a special institution for…

A Study of E-Readiness Assessment: The Case of Three Universities in Nigeria

ERIC Educational Resources Information Center

Eweni, Samuel O.

2012-01-01

This study investigated the readiness of three higher educational institutions in Nigeria in their attempt to introduce and maintain technology-driven services to students, faculty, and support staff. The prerequisites for participation in the digital, networked economy include the affordable ICT, reliable electric supply, reliable and up-to-date…

A new approach to power quality and electricity reliability monitoring-case study illustrations of the capabilities of the I-GridTM system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Divan, Deepak; Brumsickle, William; Eto, Joseph

2003-04-01

This report describes a new approach for collecting information on power quality and reliability and making it available in the public domain. Making this information readily available in a form that is meaningful to electricity consumers is necessary for enabling more informed private and public decisions regarding electricity reliability. The system dramatically reduces the cost (and expertise) needed for customers to obtain information on the most significant power quality events, called voltage sags and interruptions. The system also offers widespread access to information on power quality collected from multiple sites and the potential for capturing information on the impacts ofmore » power quality problems, together enabling a wide variety of analysis and benchmarking to improve system reliability. Six case studies demonstrate selected functionality and capabilities of the system, including: Linking measured power quality events to process interruption and downtime; Demonstrating the ability to correlate events recorded by multiple monitors to narrow and confirm the causes of power quality events; and Benchmarking power quality and reliability on a firm and regional basis.« less

The Nordic concept of reactive psychosis--a multicenter reliability study.

PubMed

Hansen, H; Dahl, A A; Bertelsen, A; Birket-Smith, M; von Knorring, L; Ottosson, J O; Pakaslahti, A; Retterstøl, N; Salvesen, C; Thorsteinsson, G

1992-07-01

Reactive psychosis is a common diagnosis in the Nordic countries (Norway, Sweden, Denmark, Finland and Iceland) and in several other parts of the world. In ICD-9 and DSM-III-R, the concept is defined more narrowly than in the Nordic tradition. In this study we examined the interrater reliability of the Nordic concept by the case-summary method between clinicians from 9 university departments in the Nordic countries. The results show that Nordic psychiatrists have a reasonably reliable concept of reactive psychosis, and that this psychosis can be diagnosed as reliably as schizophrenia and affective psychosis.

Scientific Inquiry Competency Perception Scale (The Case of Kazak Post-Graduate Students) Reliability and Validity Study

ERIC Educational Resources Information Center

Gelisli, Yücel; Beisenbayeva, Lyazzat

2017-01-01

The purpose of the current study is to develop a reliable scale to be used to determine the scientific inquiry competency perception of post-graduate students engaged in post-graduate studies in the field of educational sciences and teacher education in Kazakhstan. The study employed the descriptive method. Within the context of the study, a scale…

Applying Resource Utilization Groups (RUG-III) in Hong Kong nursing homes.

PubMed

Chou, Kee-Lee; Chi, Iris; Leung, Joe C B

2008-01-01

Resource Utilization Groups III (RUG-III) is a case-mix system developed in the United States for categorization of nursing home residents and the financing of residential care services. In Hong Kong, RUG-III is based on several board groups of residents. The aim of this study was to examine the reliability and validity of the RUG-III in Hong Kong nursing homes. A cross-sectional survey was conducted in seven residential facilities operated by one agency. Residents ( N = 1,127) were assessed by the Minimum Data Set (MDS) and nursing as well as auxiliary staff care times were recorded within 2 weeks before or after the completion of MDS assessment. Forty-five out 1,127 residents were re-interviewed by an independent assessor to assess the inter-rater reliability. The inter-rater reliability of MDS assessment was excellent (kappa = 0.76) and the original RUG-III accounted for about 30 per cent of nursing staff time. Results provide preliminary evidence to support that RUG-III is a reliable and valid case-mix system for Hong Kong nursing homes, but future studies must be explored to reduce the variance of resource use explained by this case-mix system.

Validity Evidence and Scoring Guidelines for Standardized Patient Encounters and Patient Notes From a Multisite Study of Clinical Performance Examinations in Seven Medical Schools.

PubMed

Park, Yoon Soo; Hyderi, Abbas; Heine, Nancy; May, Win; Nevins, Andrew; Lee, Ming; Bordage, Georges; Yudkowsky, Rachel

2017-11-01

To examine validity evidence of local graduation competency examination scores from seven medical schools using shared cases and to provide rater training protocols and guidelines for scoring patient notes (PNs). Between May and August 2016, clinical cases were developed, shared, and administered across seven medical schools (990 students participated). Raters were calibrated using training protocols, and guidelines were developed collaboratively across sites to standardize scoring. Data included scores from standardized patient encounters for history taking, physical examination, and PNs. Descriptive statistics were used to examine scores from the different assessment components. Generalizability studies (G-studies) using variance components were conducted to estimate reliability for composite scores. Validity evidence was collected for response process (rater perception), internal structure (variance components, reliability), relations to other variables (interassessment correlations), and consequences (composite score). Student performance varied by case and task. In the PNs, justification of differential diagnosis was the most discriminating task. G-studies showed that schools accounted for less than 1% of total variance; however, for the PNs, there were differences in scores for varying cases and tasks across schools, indicating a school effect. Composite score reliability was maximized when the PN was weighted between 30% and 40%. Raters preferred using case-specific scoring guidelines with clear point-scoring systems. This multisite study presents validity evidence for PN scores based on scoring rubric and case-specific scoring guidelines that offer rigor and feedback for learners. Variability in PN scores across participating sites may signal different approaches to teaching clinical reasoning among medical schools.

Exploring Equivalent Forms Reliability Using a Key Stage 2 Reading Test

ERIC Educational Resources Information Center

Benton, Tom

2013-01-01

This article outlines an empirical investigation into equivalent forms reliability using a case study of a national curriculum reading test. Within the situation being studied, there has been a genuine attempt to create several equivalent forms and so it is of interest to compare the actual behaviour of the relationship between these forms to the…

Interrater reliability of identifying indicators of posterior ligamentous complex disruption when plain films are indeterminate in thoracolumbar injuries.

PubMed

Schweitzer, Karl M; Vaccaro, Alexander R; Harrop, James S; Hurlbert, John; Carrino, John A; Rechtine, Glenn R; Schwartz, David G; Alanay, Ahmet; Sharma, Dinesh K; Anderson, D Greg; Lee, Joon Y; Arnold, Paul M

2007-09-01

The Spine Trauma Study Group (STSG) has proposed a novel thoracolumbar injury classification system and score (TLICS) in an attempt to define traumatic spinal injuries and direct appropriate management schemes objectively. The TLICS assigns specific point values based on three variables to generate a final severity score that guides potential treatment options. Within this algorithm, significant emphasis has been placed on posterior ligamentous complex (PLC) integrity. The purpose of this study was to determine the interrater reliability of indicators surgeons use when assessing PLC disruption on imaging studies, including computed tomography (CT) and magnetic resonance imaging (MRI). Orthopedic surgeons and neurosurgeons retrospectively reviewed a series of thoracolumbar injury case studies. Thirteen case studies, including images, were distributed to STSG members for individual, independent evaluation of the following three criteria: (1) diastasis of the facet joints on CT; (2) posterior edema-like signal in the region of PLC components on sagittal T2-weighted fat saturation (FAT SAT) MRI; and (3) disrupted PLC components on sagittal T1-weighted MRI. Interrater agreement on the presence or absence of each of the three criteria in each of the 13 cases was assessed. Absolute interrater percent agreement on diastasis of the facet joints on CT and posterior edema-like signal in the region of PLC components on sagittal T2-weighted FAT SAT MRI was similar (agreement 70.5%). Interrater agreement on disrupted PLC components on sagittal T1-weighted MRI was 48.9%. Facet joint diastasis on CT was the most reliable indicator of PLC disruption as assessed by both Cohen's kappa (kappa = 0.395) and intraclass correlation coefficient (ICC 0.430). The interrater reliability of assessing diastasis of the facet joints on CT had fair to moderate agreement. The reliability of assessing the posterior edema-like signal in the region of PLC components was lower but also fair, whereas the reliability of identifying disrupted PLC components was poor.

Use of Fine Needle Aspirate from Peripheral Nerves of Pure-neural Leprosy for Cytology and Polymerase Chain Reaction to Confirm the Diagnosis: A Follow-up Study of 4 Years.

PubMed

De, Abhishek; Hasanoor Reja, Abu Hena; Aggarwal, Ishad; Sen, Sumit; Sil, Amrita; Bhattacharya, Basudev; Sharma, Nidhi; Ansari, Asad; Sarda, Aarti; Chatterjee, Gobinda; Das, Sudip

2017-01-01

Pure neural leprosy (PNL) still remains a diagnostic challenge because of the absence of sine qua non skin lesions of leprosy and a confirmatory diagnostic method. The authors had earlier described a simple yet objective technique of combining fine needle aspiration cytology (FNAC) coupled with a multiplex polymerase chain reaction (PCR) in a pilot study, wherein the technique showed promise of a reliable diagnostic tool. In the pursuit of further evidence, the authors carried out a 4-year study with PNL cases to find the efficacy and reliability of the said method in a larger sample size. This study was conducted to find the efficacy, reliability, and reproducibility of FNAC coupled with multiplex PCR and Ziehl-Neelsen (ZN) staining in identifying the cases of PNL. All cases that were suspected to be suffering from PNL, following evaluation by two independent observers were included in the study and were subjected to FNAC from the affected nerve, and the aspirates were evaluated for cytology, ZN staining, and multiplex PCR for Mycobacterium leprae genome. In addition, serum anti-PGL1 levels were also performed in all the study subjects. Fifteen non-PNL cases were also included in the control arm. A total of 47 cases were included in the test arm and subjected to FNAC. Conventional ZN staining could demonstrate acid-fast bacilli (AFB) in only 15 out of 47 cases (31.91%) while M. leprae DNA could be elicited in 37 (78.72%) cases by the multiplex PCR. Only 13 (27.65%) out of 47 cases showed anti-PGLI-1 antibody positivity. On cytological examination of the nerve aspirates, only 11 (23.40%) cases showed epithelioid cells whereas nonspecific inflammation was seen in 26 (75.60%) cases. The results of this study conducted over a larger sample size corroborate with the findings of our pilot study. In a resource poor set up, FNAC in combination with ZN staining and multiplex PCR is a rapid, simple, and easily performed test, which can give a reproducible and objective diagnosis in cases of PNL.

Reliability Prediction Approaches For Domestic Intelligent Electric Energy Meter Based on IEC62380

NASA Astrophysics Data System (ADS)

Li, Ning; Tong, Guanghua; Yang, Jincheng; Sun, Guodong; Han, Dongjun; Wang, Guixian

2018-01-01

The reliability of intelligent electric energy meter is a crucial issue considering its large calve application and safety of national intelligent grid. This paper developed a procedure of reliability prediction for domestic intelligent electric energy meter according to IEC62380, especially to identify the determination of model parameters combining domestic working conditions. A case study was provided to show the effectiveness and validation.

Assessment of Reliable Change Using 95% Credible Intervals for the Differences in Proportions: A Statistical Analysis for Case-Study Methodology

ERIC Educational Resources Information Center

Unicomb, Rachael; Colyvas, Kim; Harrison, Elisabeth; Hewat, Sally

2015-01-01

Purpose: Case-study methodology studying change is often used in the field of speech-language pathology, but it can be criticized for not being statistically robust. Yet with the heterogeneous nature of many communication disorders, case studies allow clinicians and researchers to closely observe and report on change. Such information is valuable…

A Bayesian approach to reliability and confidence

NASA Technical Reports Server (NTRS)

Barnes, Ron

1989-01-01

The historical evolution of NASA's interest in quantitative measures of reliability assessment is outlined. The introduction of some quantitative methodologies into the Vehicle Reliability Branch of the Safety, Reliability and Quality Assurance (SR and QA) Division at Johnson Space Center (JSC) was noted along with the development of the Extended Orbiter Duration--Weakest Link study which will utilize quantitative tools for a Bayesian statistical analysis. Extending the earlier work of NASA sponsor, Richard Heydorn, researchers were able to produce a consistent Bayesian estimate for the reliability of a component and hence by a simple extension for a system of components in some cases where the rate of failure is not constant but varies over time. Mechanical systems in general have this property since the reliability usually decreases markedly as the parts degrade over time. While they have been able to reduce the Bayesian estimator to a simple closed form for a large class of such systems, the form for the most general case needs to be attacked by the computer. Once a table is generated for this form, researchers will have a numerical form for the general solution. With this, the corresponding probability statements about the reliability of a system can be made in the most general setting. Note that the utilization of uniform Bayesian priors represents a worst case scenario in the sense that as researchers incorporate more expert opinion into the model, they will be able to improve the strength of the probability calculations.

Reliability and validity: Part II.

PubMed

Davis, Debora Winders

2004-01-01

Determining measurement reliability and validity involves complex processes. There is usually room for argument about most instruments. It is important that the researcher clearly describes the processes upon which she made the decision to use a particular instrument, and presents the evidence available showing that the instrument is reliable and valid for the current purposes. In some cases, the researcher may need to conduct pilot studies to obtain evidence upon which to decide whether the instrument is valid for a new population or a different setting. In all cases, the researcher must present a clear and complete explanation for the choices, she has made regarding reliability and validity. The consumer must then judge the degree to which the researcher has provided adequate and theoretically sound rationale. Although I have tried to touch on most of the important concepts related to measurement reliability and validity, it is beyond the scope of this column to be exhaustive. There are textbooks devoted entirely to specific measurement issues if readers require more in-depth knowledge.

Reliability of excess-flow check-valves in turbine lubrication systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dundas, R.E.

1996-12-31

Reliability studies on excess-flow check valves installed in a gas turbine lubrication system for prevention of spray fires subsequent to fracture or separation of lube lines were conducted. Fault-tree analyses are presented for the case of failure of a valve to close when called upon by separation of a downstream line, as well as for the case of accidental closure during normal operation, leading to interruption of lubricating oil flow to a bearing. The probabilities of either of these occurrences are evaluated. The results of a statistical analysis of accidental closure of excess-flow check valves in commercial airplanes in themore » period 1986--91 are also given, as well as a summary of reliability studies on the use of these valves in residential gas installations, conducted under the sponsorship of the Gas Research Institute.« less

Assessment of the reliability of data collected for the Department of Veterans Affairs national surgical quality improvement program.

PubMed

Davis, Chester L; Pierce, John R; Henderson, William; Spencer, C David; Tyler, Christine; Langberg, Robert; Swafford, Jennan; Felan, Gladys S; Kearns, Martha A; Booker, Brigitte

2007-04-01

The Office of the Medical Inspector of the Department of Veterans Affairs (VA) studied the reliability of data collected by the VA's National Surgical Quality Improvement Program (NSQIP). The study focused on case selection bias, accuracy of reports on patients who died, and interrater reliability measurements of patient risk variables and outcomes. Surgical data from a sample of 15 VA medical centers were analyzed. For case selection bias, reviewers applied NSQIP criteria to include or exclude 2,460 patients from the database, comparing their results with those of NSQIP staff. For accurate reporting of patients who died, reviewers compared Social Security numbers of 10,444 NSQIP records with those found in the VA Beneficiary Identification and Records Locator Subsystem, VA Patient Treatment Files, and Social Security Administration death files. For measurement of interrater reliability, reviewers reabstracted 59 variables in each of 550 patient medical records that also were recorded in the NSQIP database. On case selection bias, the reviewers agreed with NSQIP decisions on 2,418 (98%) of the 2,460 cases. Computer record matching identified 4 more deaths than the NSQIP total of 198, a difference of about 2%. For 52 of the categorical variables, agreement, uncorrected for chance, was 96%. For 48 of 52 categorical variables, kappas ranged from 0.61 to 1.0 (substantial to almost perfect agreement); none of the variables had kappas of less than 0.20 (slight to poor agreement). This sample of medical centers shows adherence to criteria in selecting cases for the NSQIP database, for reporting deaths, and for collecting patient risk variables.

The Reliability and Legality of Online Education

ERIC Educational Resources Information Center

Agbebaku, C. A.; Adavbiele, A. Justina

2016-01-01

Today, the classroom beyond the border through online Open University education in Nigeria has made it possible for many students to obtain university degrees. However, the reliability and legality of such degrees have become questionable. This paper is a descriptive exploratory case study regarding the public and private sector end-users, whose…

It is Time the United States Air Force Changes the way it Feeds its Airmen

DTIC Science & Technology

2008-03-01

narrative , phenomenology , ethnography , case study , and grounded theory . In purpose, these strategies are...methodology) the research will be analyzed. Methodology A qualitative research methodology and specifically a case study strategy for the...well as theory building in chapter five . Finally, in regards to reliability, Yin’s (2003) case study protocol guidance was used as a means to

The interrater reliability of DSM III in children.

PubMed

Werry, J S; Methven, R J; Fitzpatrick, J; Dixon, H

1983-09-01

A total of 195 admissions to a child psychiatric inpatient unit were diagnosed independently by two to four clinicians on the basis of case presentations at the first ward-round after admission. The DSM III as a whole and the major categories were of high or acceptable reliability, though a few were clearly unreliable. The results are generally consistent with other studies. Unlike other studies, the subcategories were examined and found to vary widely in reliability both as a whole across the system and within parent major categories, throwing considerable doubt upon their utility. The results indicate the need both for improved diagnostic data-gathering techniques in child psychiatry and for more better-designed studies of reliability and, most necessarily, of validity.

A Homogenization Approach for Design and Simulation of Blast Resistant Composites

NASA Astrophysics Data System (ADS)

Sheyka, Michael

Structural composites have been used in aerospace and structural engineering due to their high strength to weight ratio. Composite laminates have been successfully and extensively used in blast mitigation. This dissertation examines the use of the homogenization approach to design and simulate blast resistant composites. Three case studies are performed to examine the usefulness of different methods that may be used in designing and optimizing composite plates for blast resistance. The first case study utilizes a single degree of freedom system to simulate the blast and a reliability based approach. The first case study examines homogeneous plates and the optimal stacking sequence and plate thicknesses are determined. The second and third case studies use the homogenization method to calculate the properties of composite unit cell made of two different materials. The methods are integrated with dynamic simulation environments and advanced optimization algorithms. The second case study is 2-D and uses an implicit blast simulation, while the third case study is 3-D and simulates blast using the explicit blast method. Both case studies 2 and 3 rely on multi-objective genetic algorithms for the optimization process. Pareto optimal solutions are determined in case studies 2 and 3. Case study 3 is an integrative method for determining optimal stacking sequence, microstructure and plate thicknesses. The validity of the different methods such as homogenization, reliability, explicit blast modeling and multi-objective genetic algorithms are discussed. Possible extension of the methods to include strain rate effects and parallel computation is also examined.

Development of a diagnostic test set to assess agreement in breast pathology: practical application of the Guidelines for Reporting Reliability and Agreement Studies (GRRAS).

PubMed

Oster, Natalia V; Carney, Patricia A; Allison, Kimberly H; Weaver, Donald L; Reisch, Lisa M; Longton, Gary; Onega, Tracy; Pepe, Margaret; Geller, Berta M; Nelson, Heidi D; Ross, Tyler R; Tosteson, Aanna N A; Elmore, Joann G

2013-02-05

Diagnostic test sets are a valuable research tool that contributes importantly to the validity and reliability of studies that assess agreement in breast pathology. In order to fully understand the strengths and weaknesses of any agreement and reliability study, however, the methods should be fully reported. In this paper we provide a step-by-step description of the methods used to create four complex test sets for a study of diagnostic agreement among pathologists interpreting breast biopsy specimens. We use the newly developed Guidelines for Reporting Reliability and Agreement Studies (GRRAS) as a basis to report these methods. Breast tissue biopsies were selected from the National Cancer Institute-funded Breast Cancer Surveillance Consortium sites. We used a random sampling stratified according to woman's age (40-49 vs. ≥50), parenchymal breast density (low vs. high) and interpretation of the original pathologist. A 3-member panel of expert breast pathologists first independently interpreted each case using five primary diagnostic categories (non-proliferative changes, proliferative changes without atypia, atypical ductal hyperplasia, ductal carcinoma in situ, and invasive carcinoma). When the experts did not unanimously agree on a case diagnosis a modified Delphi method was used to determine the reference standard consensus diagnosis. The final test cases were stratified and randomly assigned into one of four unique test sets. We found GRRAS recommendations to be very useful in reporting diagnostic test set development and recommend inclusion of two additional criteria: 1) characterizing the study population and 2) describing the methods for reference diagnosis, when applicable.

Epileptic auras and their role in driving safety in people with epilepsy.

PubMed

Punia, Vineet; Farooque, Pue; Chen, William; Hirsch, Lawrence J; Berg, Anne T; Blumenfeld, Hal

2015-11-01

The aim of our study was to evaluate the role of auras in preventing motor vehicle accidents (MVAs) among patients with medically refractory epilepsy. The Multicenter Study of Epilepsy Surgery database was used to perform a case-control study by identifying patients who had seizures while driving that led to MVAs (cases) and those who had seizures while driving without MVAs (controls). We compared presence of reliable auras and other aura-related features between the two groups. Two hundred fifteen of 553 patients reported having seizure(s) while driving; 74 were identified as "controls" and 141 as "cases." The two groups had similar demographic and clinical features. The presence of reliable auras was not different between the two groups (67% in cases vs. 65% in controls; odds ratio [OR] 0.89, 95% confidence interval [CI] 0.49-1.61, p = 0.76). In addition, the groups did not differ in the proportion of patients who reported longer (>1 min) auras (OR 0.7, 95% CI 0.28-1.76, p = 0.47), or who thought that their auras were of sufficient duration to be protective (OR 1.19, 95% CI 0.62-2.00, p = 0.77). Our study questions the long-held belief of a protective role of reliable auras against MVAs in people with epilepsy. Wiley Periodicals, Inc. © 2015 International League Against Epilepsy.

Comparison of expert and job-exposure matrix-based retrospective exposure assessment of occupational carcinogens in The Netherlands Cohort Study.

PubMed

Offermans, Nadine S M; Vermeulen, Roel; Burdorf, Alex; Peters, Susan; Goldbohm, R Alexandra; Koeman, Tom; van Tongeren, Martie; Kauppinen, T; Kant, Ijmert; Kromhout, Hans; van den Brandt, Piet A

2012-10-01

Reliable retrospective exposure assessment continues to be a challenge in most population-based studies. Several methodologies exist for estimating exposures retrospectively, of which case-by-case expert assessment and job-exposure matrices (JEMs) are commonly used. This study evaluated the reliability of exposure estimates for selected carcinogens obtained through three JEMs by comparing the estimates with case-by-case expert assessment within the Netherlands Cohort Study (NLCS). The NLCS includes 58,279 men aged 55-69 years at enrolment in 1986. For a subcohort of these men (n=1630), expert assessment is available for exposure to asbestos, polycyclic aromatic hydrocarbons (PAHs) and welding fumes. Reliability of the different JEMs (DOMJEM (asbestos, PAHs), FINJEM (asbestos, PAHs and welding fumes) and Asbestos JEM (asbestos) was determined by assessing the agreement between these JEMs and the expert assessment. Expert assessment revealed the lowest prevalence of exposure for all three exposures (asbestos 9.3%; PAHs 5.3%; welding fumes 11.7%). The DOMJEM showed the highest level of agreement with the expert assessment for asbestos and PAHs (κs=0.29 and 0.42, respectively), closely followed by the FINJEM. For welding fumes, concordance between the expert assessment and FINJEM was high (κ=0.70). The Asbestos JEM showed poor agreement with the expert asbestos assessment (κ=0.10). This study shows case-by-case expert assessment to result in the lowest prevalence of occupational exposure in the NLCS. Furthermore, the DOMJEM and FINJEM proved to be rather similar in agreement when compared with the expert assessment. The Asbestos JEM appeared to be less appropriate for use in the NLCS.

Operating room clinicians' ratings of workload: a vignette simulation study.

PubMed

Wallston, Kenneth A; Slagle, Jason M; Speroff, Ted; Nwosu, Sam; Crimin, Kimberly; Feurer, Irene D; Boettcher, Brent; Weinger, Matthew B

2014-06-01

Increased clinician workload is associated with medical errors and patient harm. The Quality and Workload Assessment Tool (QWAT) measures anticipated (pre-case) and perceived (post-case) clinical workload during actual surgical procedures using ratings of individual and team case difficulty from every operating room (OR) team member. The purpose of this study was to examine the QWAT ratings of OR clinicians who were not present in the OR but who read vignettes compiled from actual case documentation to assess interrater reliability and agreement with ratings made by clinicians involved in the actual cases. Thirty-six OR clinicians (13 anesthesia providers, 11 surgeons, and 12 nurses) used the QWAT to rate 6 cases varying from easy to moderately difficult based on actual ratings made by clinicians involved with the cases. Cases were presented and rated in random order. Before rating anticipated individual and team difficulty, the raters read prepared clinical vignettes containing case synopses and much of the same written case information that was available to the actual clinicians before the onset of each case. Then, before rating perceived individual and team difficulty, they read part 2 of the vignette consisting of detailed role-specific intraoperative data regarding the anesthetic and surgical course, unusual events, and other relevant contextual factors. Surgeons had higher interrater reliability on the QWAT than did OR nurses or anesthesia providers. For the anticipated individual and team workload ratings, there were no statistically significant differences between the actual ratings and the ratings obtained from the vignettes. There were differences for the 3 provider types in perceived individual workload for the median difficulty cases and in the perceived team workload for the median and more difficult cases. The case difficulty items on the QWAT seem to be sufficiently reliable and valid to be used in other studies of anticipated and perceived clinical workload of surgeons. Perhaps because of the limitations of the clinical documentation shown to anesthesia providers and OR nurses in the current vignette study, more evidence needs to be gathered to demonstrate the criterion-related validity of the QWAT difficulty items for assessing the workload of nonsurgeon OR clinicians.

Chronic Fatigue Syndrome and Myalgic Encephalomyelitis: Toward An Empirical Case Definition

PubMed Central

Jason, Leonard A.; Kot, Bobby; Sunnquist, Madison; Brown, Abigail; Evans, Meredyth; Jantke, Rachel; Williams, Yolonda; Furst, Jacob; Vernon, Suzanne D.

2015-01-01

Current case definitions of Myalgic Encephalomyelitis (ME) and chronic fatigue syndrome (CFS) have been based on consensus methods, but empirical methods could be used to identify core symptoms and thereby improve the reliability. In the present study, several methods (i.e., continuous scores of symptoms, theoretically and empirically derived cut off scores of symptoms) were used to identify core symptoms best differentiating patients from controls. In addition, data mining with decision trees was conducted. Our study found a small number of core symptoms that have good sensitivity and specificity, and these included fatigue, post-exertional malaise, a neurocognitive symptom, and unrefreshing sleep. Outcomes from these analyses suggest that using empirically selected symptoms can help guide the creation of a more reliable case definition. PMID:26029488

Reliability of the European Society of Human Reproduction and Embryology/European Society for Gynaecological Endoscopy and American Society for Reproductive Medicine classification systems for congenital uterine anomalies detected using three-dimensional ultrasonography.

PubMed

Ludwin, Artur; Ludwin, Inga; Kudla, Marek; Kottner, Jan

2015-09-01

To estimate the inter-rater/intrarater reliability of the European Society of Human Reproduction and Embryology/European Society for Gynaecological Endoscopy (ESHRE-ESGE) classification of congenital uterine malformations and to compare the results obtained with the reliability of the American Society for Reproductive Medicine (ASRM) classification supplemented with additional morphometric criteria. Reliability/agreement study. Private clinic. Uterine malformations (n = 50 patients, consecutively included) and normal uterus (n = 62 women, randomly selected) constituted the study. These were classified based on real-time three-dimensional ultrasound single volume transvaginal (or transrectal in the case of virgins, 4 cases) ultrasonography findings, which were assessed by an expert rater based on the ESHRE-ESGE criteria. The samples were obtained from women of reproductive age. Unprocessed three-dimensional datasets were independently evaluated offline by two experienced, blinded raters using both classification systems. The κ-values and proportions of agreement. Standardized interpretation indicated that the ESHRE-ESGE system has substantial/good or almost perfect/very good reliability (κ >0.60 and >0.80), but the interpretation of the clinically relevant cutoffs of κ-values showed insufficient reliability for clinical use (κ < 0.90), especially in the diagnosis of septate uterus. The ASRM system had sufficient reliability (κ > 0.95). The low reliability of the ESHRE-ESGE system may lead to a lack of consensus about the management of common uterine malformations and biased research interpretations. The use of the ASRM classification, supplemented with simple morphometric criteria, may be preferred if their sufficient reliability can be confirmed real-time in a large sample size. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Evaluation of General Classes of Reliability Estimators Often Used in Statistical Analyses of Quasi-Experimental Designs

NASA Astrophysics Data System (ADS)

Saini, K. K.; Sehgal, R. K.; Sethi, B. L.

2008-10-01

In this paper major reliability estimators are analyzed and there comparatively result are discussed. There strengths and weaknesses are evaluated in this case study. Each of the reliability estimators has certain advantages and disadvantages. Inter-rater reliability is one of the best ways to estimate reliability when your measure is an observation. However, it requires multiple raters or observers. As an alternative, you could look at the correlation of ratings of the same single observer repeated on two different occasions. Each of the reliability estimators will give a different value for reliability. In general, the test-retest and inter-rater reliability estimates will be lower in value than the parallel forms and internal consistency ones because they involve measuring at different times or with different raters. Since reliability estimates are often used in statistical analyses of quasi-experimental designs.

Case Study: Fuel Cells Provide Combined Heat and Power at Verizon's Garden City Central Office

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2010-12-01

This case study describes how Verizon's Central Office in Garden City, NY, installed a 1.4-MW phosphoric acid fuel cell system as an alternative solution to bolster electric reliability, optimize the company's energy use, and reduce costs in an environmentally responsible manner.

How School Librarians Can Contribute to the Personal Growth of Students with Disabilities.

ERIC Educational Resources Information Center

Murray, Janet

2000-01-01

Discusses building self-esteem and confidence of disabled students through school library programs, based on Australian case studies. Topics include validity and reliability of case studies; the influence of teacher attitudes on student attitudes toward the disabled; physical accessibility; information literacy; information technology use; and…

Use of Fine Needle Aspirate from Peripheral Nerves of Pure-neural Leprosy for Cytology and Polymerase Chain Reaction to Confirm the Diagnosis: A Follow-up Study of 4 Years

PubMed Central

De, Abhishek; Hasanoor Reja, Abu Hena; Aggarwal, Ishad; Sen, Sumit; Sil, Amrita; Bhattacharya, Basudev; Sharma, Nidhi; Ansari, Asad; Sarda, Aarti; Chatterjee, Gobinda; Das, Sudip

2017-01-01

Background: Pure neural leprosy (PNL) still remains a diagnostic challenge because of the absence of sine qua non skin lesions of leprosy and a confirmatory diagnostic method. The authors had earlier described a simple yet objective technique of combining fine needle aspiration cytology (FNAC) coupled with a multiplex polymerase chain reaction (PCR) in a pilot study, wherein the technique showed promise of a reliable diagnostic tool. In the pursuit of further evidence, the authors carried out a 4-year study with PNL cases to find the efficacy and reliability of the said method in a larger sample size. Aim: This study was conducted to find the efficacy, reliability, and reproducibility of FNAC coupled with multiplex PCR and Ziehl-Neelsen (ZN) staining in identifying the cases of PNL. Materials and Methods: All cases that were suspected to be suffering from PNL, following evaluation by two independent observers were included in the study and were subjected to FNAC from the affected nerve, and the aspirates were evaluated for cytology, ZN staining, and multiplex PCR for Mycobacterium leprae genome. In addition, serum anti-PGL1 levels were also performed in all the study subjects. Fifteen non-PNL cases were also included in the control arm. Results: A total of 47 cases were included in the test arm and subjected to FNAC. Conventional ZN staining could demonstrate acid-fast bacilli (AFB) in only 15 out of 47 cases (31.91%) while M. leprae DNA could be elicited in 37 (78.72%) cases by the multiplex PCR. Only 13 (27.65%) out of 47 cases showed anti-PGLI-1 antibody positivity. On cytological examination of the nerve aspirates, only 11 (23.40%) cases showed epithelioid cells whereas nonspecific inflammation was seen in 26 (75.60%) cases. Conclusion: The results of this study conducted over a larger sample size corroborate with the findings of our pilot study. In a resource poor set up, FNAC in combination with ZN staining and multiplex PCR is a rapid, simple, and easily performed test, which can give a reproducible and objective diagnosis in cases of PNL. PMID:29263539

Epileptic auras and their role in driving safety in people with epilepsy

PubMed Central

Punia, Vineet; Farooque, Pue; Chen, William; Hirsch, Lawrence J.; Berg, Anne T.; Blumenfeld, Hal

2015-01-01

Summary The aim of our study was to evaluate the role of auras in preventing motor vehicle accidents (MVA) among medically-refractory epilepsy patients. The Multicenter Study of Epilepsy Surgery database was used to perform a case-control study by identifying patients who had seizures while driving that led to MVAs (Cases) and those who had seizures while driving without MVAs (Controls). We compared presence of reliable auras and other aura-related features between the two groups. 215 out of 553 patients reported having seizure(s) while driving; 74 were identified as ‘Controls’ and 141 as ‘Cases’. The two groups had similar demographic and clinical features. The presence of reliable auras was not different between the two groups (67% in Cases vs 65% in Controls; OR = 0.89, 95% CI 0.49 – 1.61, p = 0.76). In addition, the groups did not differ in the proportion of patients who reported longer (>1 minute) auras (OR 0.7; 95% CI 0.28 – 1.76; p = 0.47), or who thought that their auras were sufficiently long to protect themselves (OR 1.19; 95% CI 0.62 – 2.00; p = 0.77). Our study questions the long-held belief of a protective role of reliable auras against MVAs in people with epilepsy. PMID:26391317

Test-retest reliability of the Progressive Isoinertial Lifting Evaluation (PILE).

PubMed

Lygren, Hildegunn; Dragesund, Tove; Joensen, Jón; Ask, Tove; Moe-Nilssen, Rolf

2005-05-01

A repeated measures single group design. To investigate test-retest reliability of Progressive Isoinertial Lifting Evaluation on patients with long lasting musculoskeletal problems related to the lumbar spine. Test-retest reliability has been satisfactory in healthy men. Test-retest reliability for clinical populations has not been reported. A total of 31 patients (17 women and 14 men) with long lasting low back pain participated in the study. The patients were tested twice at an interval of 2 days and at the same time of the day. The heaviest load that the patient could lift 4 times was used as outcome measure. The error of measurement indicates that the true result in 95% of cases will be within +/-4.5 kg from the measured value, while the difference between 2 measurements in 95% of cases will be less than 6.4 kg. Intra-class correlation (1,1) was 0.91. Relative test-retest reliability was high assessed by intra-class correlation, but absolute measurement variability reported as the smallest detectable difference has relevance for the interpretation of clinical test results and should also be considered.

Reliability analysis of the AOSpine thoracolumbar spine injury classification system by a worldwide group of naïve spinal surgeons.

PubMed

Kepler, Christopher K; Vaccaro, Alexander R; Koerner, John D; Dvorak, Marcel F; Kandziora, Frank; Rajasekaran, Shanmuganathan; Aarabi, Bizhan; Vialle, Luiz R; Fehlings, Michael G; Schroeder, Gregory D; Reinhold, Maximilian; Schnake, Klaus John; Bellabarba, Carlo; Cumhur Öner, F

2016-04-01

The aims of this study were (1) to demonstrate the AOSpine thoracolumbar spine injury classification system can be reliably applied by an international group of surgeons and (2) to delineate those injury types which are difficult for spine surgeons to classify reliably. A previously described classification system of thoracolumbar injuries which consists of a morphologic classification of the fracture, a grading system for the neurologic status and relevant patient-specific modifiers was applied to 25 cases by 100 spinal surgeons from across the world twice independently, in grading sessions 1 month apart. The results were analyzed for classification reliability using the Kappa coefficient (κ). The overall Kappa coefficient for all cases was 0.56, which represents moderate reliability. Kappa values describing interobserver agreement were 0.80 for type A injuries, 0.68 for type B injuries and 0.72 for type C injuries, all representing substantial reliability. The lowest level of agreement for specific subtypes was for fracture subtype A4 (Kappa = 0.19). Intraobserver analysis demonstrated overall average Kappa statistic for subtype grading of 0.68 also representing substantial reproducibility. In a worldwide sample of spinal surgeons without previous exposure to the recently described AOSpine Thoracolumbar Spine Injury Classification System, we demonstrated moderate interobserver and substantial intraobserver reliability. These results suggest that most spine surgeons can reliably apply this system to spine trauma patients as or more reliably than previously described systems.

Combining web-based tools for transparent evaluation of data for risk assessment: developmental effects of bisphenol A on the mammary gland as a case study.

PubMed

Molander, Linda; Hanberg, Annika; Rudén, Christina; Ågerstrand, Marlene; Beronius, Anna

2017-03-01

Different tools have been developed that facilitate systematic and transparent evaluation and handling of toxicity data in the risk assessment process. The present paper sets out to explore the combined use of two web-based tools for study evaluation and identification of reliable data relevant to health risk assessment. For this purpose, a case study was performed using in vivo toxicity studies investigating low-dose effects of bisphenol A on mammary gland development. The reliability of the mammary gland studies was evaluated using the Science in Risk Assessment and Policy (SciRAP) criteria for toxicity studies. The Health Assessment Workspace Collaborative (HAWC) was used for characterizing and visualizing the mammary gland data in terms of type of effects investigated and reported, and the distribution of these effects within the dose interval. It was then investigated whether there was any relationship between study reliability and the type of effects reported and/or their distribution in the dose interval. The combination of the SciRAP and HAWC tools allowed for transparent evaluation and visualization of the studies investigating developmental effects of BPA on the mammary gland. The use of these tools showed that there were no apparent differences in the type of effects and their distribution in the dose interval between the five studies assessed as most reliable and the whole data set. Combining the SciRAP and HAWC tools was found to be a useful approach for evaluating in vivo toxicity studies and identifying reliable and sensitive information relevant to regulatory risk assessment of chemicals. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

The Reliability and Validity of the Thoracolumbar Injury Classification System in Pediatric Spine Trauma.

PubMed

Savage, Jason W; Moore, Timothy A; Arnold, Paul M; Thakur, Nikhil; Hsu, Wellington K; Patel, Alpesh A; McCarthy, Kathryn; Schroeder, Gregory D; Vaccaro, Alexander R; Dimar, John R; Anderson, Paul A

2015-09-15

The thoracolumbar injury classification system (TLICS) was evaluated in 20 consecutive pediatric spine trauma cases. The purpose of this study was to determine the reliability and validity of the TLICS in pediatric spine trauma. The TLICS was developed to improve the categorization and management of thoracolumbar trauma. TLICS has been shown to have good reliability and validity in the adult population. The clinical and radiographical findings of 20 pediatric thoracolumbar fractures were prospectively presented to 20 surgeons with disparate levels of training and experience with spinal trauma. These injuries were consecutively scored using the TLICS. Cohen unweighted κ coefficients and Spearman rank order correlation values were calculated for the key parameters (injury morphology, status of posterior ligamentous complex, neurological status, TLICS total score, and proposed management) to assess the inter-rater reliabilities. Five surgeons scored the same cases 3 months later to assess the intra-rater reliability. The actual management of each case was then compared with the treatment recommended by the TLICS algorithm to assess validity. The inter-rater κ statistics of all subgroups (injury morphology, status of the posterior ligamentous complex, neurological status, TLICS total score, and proposed treatment) were within the range of moderate to substantial reproducibility (0.524-0.958). All subgroups had excellent intra-rater reliability (0.748-1.000). The various indices for validity were calculated (80.3% correct, 0.836 sensitivity, 0.785 specificity, 0.676 positive predictive value, 0.899 negative predictive value). Overall, TLICS demonstrated good validity. The TLICS has good reliability and validity when used in the pediatric population. The inter-rater reliability of predicting management and indices for validity are lower than those in adults with thoracolumbar fractures, which is likely due to differences in the way children are treated for certain types of injuries. TLICS can be used to reliably categorize thoracolumbar injuries in the pediatric population; however, modifications may be needed to better guide treatment in this specific patient population. 4.

Students' and Teacher's Experiences of the Validity and Reliability of Assessment in a Bioscience Course

ERIC Educational Resources Information Center

Räisänen, Milla; Tuononen, Tarja; Postareff, Liisa; Hailikari, Telle; Virtanen, Viivi

2016-01-01

This case study explores the assessment of students' learning outcomes in a second-year lecture course in biosciences. The aim is to deeply explore the teacher's and the students' experiences of the validity and reliability of assessment and to compare those perspectives. The data were collected through stimulated recall interviews. The results…

An assessment of the inter-rater reliability of the ASA physical status score in the orthopaedic trauma population.

PubMed

Ihejirika, Rivka C; Thakore, Rachel V; Sathiyakumar, Vasanth; Ehrenfeld, Jesse M; Obremskey, William T; Sethi, Manish K

2015-04-01

Although recent literature has demonstrated the utility of the ASA score in predicting postoperative length of stay, complication risk and potential utilization of other hospital resources, the ASA score has been inconsistently assigned by anaesthesia providers. This study tested the reliability of assignment of the ASA score classification by both attending anaesthesiologists and anaesthesia residents specifically among the orthopaedic trauma patient population. Nine case-based scenarios were created involving preoperative patients with isolated operative orthopaedic trauma injuries. The cases were created and assigned a reference score by both an attending anaesthesiologist and orthopaedic trauma surgeon. Attending and resident anaesthesiologists were asked to assign an ASA score for each case. Rater versus reference and inter-rater agreement amongst respondents was then analyzed utilizing Fleiss's Kappa and weighted and unweighted Cohen's Kappa. Thirty three individuals provided ASA scores for each of the scenarios. The average rater versus reference reliability was substantial (Kw=0.78, SD=0.131, 95% CI=0.73-0.83). The average rater versus reference Kuw was also substantial (Kuw=0.64, SD=0.21, 95% CI=0.56-0.71). The inter-rater reliability as evaluated by Fleiss's Kappa was moderate (K=0.51, p<.001). An inter-rater comparison within the group of attendings (K=0.50, p<.001) and within the group of residents were both moderate (K=0.55, p<.001). There was a significant increase in the level of inter-rater reliability from the self-reported 'very uncomfortable' participants to the 'very comfortable' participants (uncomfortable K=0.43, comfortable K=0.59, p<.001). This study shows substantial agreement strength for reliability of the ASA score among anaesthesiologists when evaluating orthopaedic trauma patients. The significant increase in inter-rater reliability based on anaesthesiologists' comfort with the ASA scoring method implies a need for further evaluation of ASA assessment training and routine use on the ground. These findings support the use of the ASA score as a statistically reliable tool in orthopaedic trauma. Copyright © 2014 Elsevier Ltd. All rights reserved.

Fatigue after stroke: the development and evaluation of a case definition.

PubMed

Lynch, Joanna; Mead, Gillian; Greig, Carolyn; Young, Archie; Lewis, Susan; Sharpe, Michael

2007-11-01

While fatigue after stroke is a common problem, it has no generally accepted definition. Our aim was to develop a case definition for post-stroke fatigue and to test its psychometric properties. A case definition with face validity and an associated structured interview was constructed. After initial piloting, the feasibility, reliability (test-retest and inter-rater) and concurrent validity (in relation to four fatigue severity scales) were determined in 55 patients with stroke. All participating patients provided satisfactory answers to all the case definition probe questions demonstrating its feasibility For test-retest reliability, kappa was 0.78 (95% CI, 0.57-0.94, P<.01) and for inter-rater reliability kappa was 0.80 (95% CI, 0.62-0.99, P<.01). Patients fulfilling the case definition also had substantially higher fatigue scores on four fatigue severity scales (P<.001) indicating concurrent validity. The proposed case definition is feasible to administer and reliable in practice, and there is evidence of concurrent validity. It requires further evaluation in different settings.

The impact of leadership and team behavior on standard of care delivered during human patient simulation: a pilot study for undergraduate medical students.

PubMed

Carlson, Jim; Min, Elana; Bridges, Diane

2009-01-01

Methodology to train team behavior during simulation has received increased attention, but standard performance measures are lacking, especially at the undergraduate level. Our purposes were to develop a reliable team behavior measurement tool and explore the relationship between team behavior and the delivery of an appropriate standard of care specific to the simulated case. Authors developed a unique team measurement tool based on previous work. Trainees participated in a simulated event involving the presentation of acute dyspnea. Performance was rated by separate raters using the team behavior measurement tool. Interrater reliability was assessed. The relationship between team behavior and the standard of care delivered was explored. The instrument proved to be reliable for this case and group of raters. Team behaviors had a positive relationship with the standard of medical care delivered specific to the simulated case. The methods used provide a possible method for training and assessing team performance during simulation.

Choosing a reliability inspection plan for interval censored data

DOE PAGES

Lu, Lu; Anderson-Cook, Christine Michaela

2017-04-19

Reliability test plans are important for producing precise and accurate assessment of reliability characteristics. This paper explores different strategies for choosing between possible inspection plans for interval censored data given a fixed testing timeframe and budget. A new general cost structure is proposed for guiding precise quantification of total cost in inspection test plan. Multiple summaries of reliability are considered and compared as the criteria for choosing the best plans using an easily adapted method. Different cost structures and representative true underlying reliability curves demonstrate how to assess different strategies given the logistical constraints and nature of the problem. Resultsmore » show several general patterns exist across a wide variety of scenarios. Given the fixed total cost, plans that inspect more units with less frequency based on equally spaced time points are favored due to the ease of implementation and consistent good performance across a large number of case study scenarios. Plans with inspection times chosen based on equally spaced probabilities offer improved reliability estimates for the shape of the distribution, mean lifetime, and failure time for a small fraction of population only for applications with high infant mortality rates. The paper uses a Monte Carlo simulation based approach in addition to the common evaluation based on the asymptotic variance and offers comparison and recommendation for different applications with different objectives. Additionally, the paper outlines a variety of different reliability metrics to use as criteria for optimization, presents a general method for evaluating different alternatives, as well as provides case study results for different common scenarios.« less

Choosing a reliability inspection plan for interval censored data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, Lu; Anderson-Cook, Christine Michaela

Reliability test plans are important for producing precise and accurate assessment of reliability characteristics. This paper explores different strategies for choosing between possible inspection plans for interval censored data given a fixed testing timeframe and budget. A new general cost structure is proposed for guiding precise quantification of total cost in inspection test plan. Multiple summaries of reliability are considered and compared as the criteria for choosing the best plans using an easily adapted method. Different cost structures and representative true underlying reliability curves demonstrate how to assess different strategies given the logistical constraints and nature of the problem. Resultsmore » show several general patterns exist across a wide variety of scenarios. Given the fixed total cost, plans that inspect more units with less frequency based on equally spaced time points are favored due to the ease of implementation and consistent good performance across a large number of case study scenarios. Plans with inspection times chosen based on equally spaced probabilities offer improved reliability estimates for the shape of the distribution, mean lifetime, and failure time for a small fraction of population only for applications with high infant mortality rates. The paper uses a Monte Carlo simulation based approach in addition to the common evaluation based on the asymptotic variance and offers comparison and recommendation for different applications with different objectives. Additionally, the paper outlines a variety of different reliability metrics to use as criteria for optimization, presents a general method for evaluating different alternatives, as well as provides case study results for different common scenarios.« less

Examination of the Test-Retest Reliability of a Computerized Neurocognitive Test Battery.

PubMed

Nakayama, Yusuke; Covassin, Tracey; Schatz, Philip; Nogle, Sally; Kovan, Jeff

2014-08-01

Test-retest reliability is a critical issue in the utility of computer-based neurocognitive assessment paradigms employing baseline and postconcussion tests. Researchers have reported low test-retest reliability for the Immediate Post Concussion Assessment and Cognitive Testing (ImPACT) across an interval of 45 and 50 days. To re-examine the test-retest reliability of the ImPACT between baseline, 45 days, and 50 days. Descriptive laboratory study. Eighty-five physically active college students (51 male, 34 female) volunteered for this study. Participants completed the ImPACT as well as a 15-item memory test at baseline, 45 days, and 50 days. Intraclass correlation coefficients (ICCs) were calculated for ImPACT composite scores, and change scores were calculated using reliable change indices (RCIs) and regression-based methods (RBMs) at 80% and 95% confidence intervals (CIs). The respective ICCs for baseline to day 45, day 45 to day 50, baseline to day 50, and overall were as follows: verbal memory (0.76, 0.69, 0.65, and 0.78), visual memory (0.72, 0.66, 0.60, and 0.74), visual motor (processing) speed (0.87, 0.88, 0.85, and 0.91), and reaction time (0.67, 0.81, 0.71, and 0.80). All ICCs exceeded the threshold value of 0.60 for acceptable test-retest reliability. All cases fell well within the 80% CI for both the RCI and RBM, while 1% to 5% of cases fell outside the 95% CI for the RCI and 1% for the RBM. Results suggest that the ImPACT is a reliable neurocognitive test battery at 45 and 50 days after the baseline assessment. The current findings agree with those of other reliability studies that have reported acceptable ICCs across 30-day to 1-year testing intervals, and they support the utility of the ImPACT for the multidisciplinary approach to concussion management. This study suggests that the computerized neurocognitive test battery, ImPACT, is a reliable test for postconcussion serial assessments. However, when managing concussed athletes, the ImPACT should not be used as a stand-alone measure. © 2014 The Author(s).

Increased Reliability for Single-Case Research Results: Is the Bootstrap the Answer?

ERIC Educational Resources Information Center

Parker, Richard I.

2006-01-01

There is need for objective and reliable single-case research (SCR) results in the movement toward evidence-based interventions (EBI), for inclusion in meta-analyses, and for funding accountability in clinical contexts. Yet SCR deals with data that often do not conform to parametric data assumptions and that yield results of low reliability. A…

BurnCase 3D software validation study: Burn size measurement accuracy and inter-rater reliability.

PubMed

Parvizi, Daryousch; Giretzlehner, Michael; Wurzer, Paul; Klein, Limor Dinur; Shoham, Yaron; Bohanon, Fredrick J; Haller, Herbert L; Tuca, Alexandru; Branski, Ludwik K; Lumenta, David B; Herndon, David N; Kamolz, Lars-P

2016-03-01

The aim of this study was to compare the accuracy of burn size estimation using the computer-assisted software BurnCase 3D (RISC Software GmbH, Hagenberg, Austria) with that using a 2D scan, considered to be the actual burn size. Thirty artificial burn areas were pre planned and prepared on three mannequins (one child, one female, and one male). Five trained physicians (raters) were asked to assess the size of all wound areas using BurnCase 3D software. The results were then compared with the real wound areas, as determined by 2D planimetry imaging. To examine inter-rater reliability, we performed an intraclass correlation analysis with a 95% confidence interval. The mean wound area estimations of the five raters using BurnCase 3D were in total 20.7±0.9% for the child, 27.2±1.5% for the female and 16.5±0.1% for the male mannequin. Our analysis showed relative overestimations of 0.4%, 2.8% and 1.5% for the child, female and male mannequins respectively, compared to the 2D scan. The intraclass correlation between the single raters for mean percentage of the artificial burn areas was 98.6%. There was also a high intraclass correlation between the single raters and the 2D Scan visible. BurnCase 3D is a valid and reliable tool for the determination of total body surface area burned in standard models. Further clinical studies including different pediatric and overweight adult mannequins are warranted. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

Test-retest of self-reported exposure to artificial tanning devices, self-tanning creams, and sun sensitivity showed consistency.

PubMed

Beane Freeman, Laura E; Dennis, Leslie K; Lynch, Charles F; Lowe, John B; Clarke, William R

2005-04-01

Exposure to ultraviolet radiation has consistently been linked to an increased risk of melanoma. Epidemiologic studies are susceptible to measurement error, which can distort the magnitude of observed effects. Although the reliability of self-report of many sun exposure factors has been previously described in several studies, self-report of use of artificial tanning devices and self-tanning creams has been less well characterized. A mailed survey was re-administered 2-4 weeks after completion of the initial survey to 76 randomly selected participants in a case-control study of melanoma. Cases and controls were individuals diagnosed in 1999 and 2000 who were ascertained from the Iowa Cancer Registry in 2002. We assessed the consistency of self-reported use of sunlamps and self-tanning creams, sun sensitivity, and history of sunburns. There was substantial reliability in reporting the use of sunlamps or self-tanning creams (cases: Kappa (kappa)=1.0 for both exposures; controls: kappa=0.71 and 0.87, respectively). kappa estimates of 0.62-0.78 were found for overall reliability of several sun sensitivity factors. Overall, the survey instrument demonstrated substantial reproducibility for factors related to the use of sunlamps or tanning beds, self-tanning creams, and sun sensitivity factors.

Study on Distribution Reliability with Parallel and On-site Distributed Generation Considering Protection Miscoordination and Tie Line

NASA Astrophysics Data System (ADS)

Chaitusaney, Surachai; Yokoyama, Akihiko

In distribution system, Distributed Generation (DG) is expected to improve the system reliability as its backup generation. However, DG contribution in fault current may cause the loss of the existing protection coordination, e.g. recloser-fuse coordination and breaker-breaker coordination. This problem can drastically deteriorate the system reliability, and it is more serious and complicated when there are several DG sources in the system. Hence, the above conflict in reliability aspect unavoidably needs a detailed investigation before the installation or enhancement of DG is done. The model of composite DG fault current is proposed to find the threshold beyond which existing protection coordination is lost. Cases of protection miscoordination are described, together with their consequences. Since a distribution system may be tied with another system, the issues of tie line and on-site DG are integrated into this study. Reliability indices are evaluated and compared in the distribution reliability test system RBTS Bus 2.

The influence of tie strength on evolutionary games on networks: An empirical investigation

NASA Astrophysics Data System (ADS)

Buesser, Pierre; Peña, Jorge; Pestelacci, Enea; Tomassini, Marco

2011-11-01

Extending previous work on unweighted networks, we present here a systematic numerical investigation of standard evolutionary games on weighted networks. In the absence of any reliable model for generating weighted social networks, we attribute weights to links in a few ways supported by empirical data ranging from totally uncorrelated to weighted bipartite networks. The results of the extensive simulation work on standard complex network models show that, except in a case that does not seem to be common in social networks, taking the tie strength into account does not change in a radical manner the long-run steady-state behavior of the studied games. Besides model networks, we also included a real-life case drawn from a coauthorship network. In this case also, taking the weights into account only changes the results slightly with respect to the raw unweighted graph, although to draw more reliable conclusions on real social networks many more cases should be studied as these weighted networks become available.

Construct Validity and Reliability of the Tolerance Scale among Iranian College Students

ERIC Educational Resources Information Center

Ersanli, Ercümend; Mameghani, Shiva Saeighi

2016-01-01

In the present study, the Tolerance Scale developed by Ersanli (2014) was adapted to the Iranian culture, and its validity and reliability were investigated in the case of Iranian college students. The participants consisted of 552 Iranian college students (62% male, M = 20.84, S.D.: 1.53) selected using the convenience sampling method. The sample…

Neural Networks Based Approach to Enhance Space Hardware Reliability

NASA Technical Reports Server (NTRS)

Zebulum, Ricardo S.; Thakoor, Anilkumar; Lu, Thomas; Franco, Lauro; Lin, Tsung Han; McClure, S. S.

2011-01-01

This paper demonstrates the use of Neural Networks as a device modeling tool to increase the reliability analysis accuracy of circuits targeted for space applications. The paper tackles a number of case studies of relevance to the design of Flight hardware. The results show that the proposed technique generates more accurate models than the ones regularly used to model circuits.

Web-Enabled Mechanistic Case Diagramming: A Novel Tool for Assessing Students' Ability to Integrate Foundational and Clinical Sciences.

PubMed

Ferguson, Kristi J; Kreiter, Clarence D; Haugen, Thomas H; Dee, Fred R

2018-02-20

As medical schools move from discipline-based courses to more integrated approaches, identifying assessment tools that parallel this change is an important goal. The authors describe the use of test item statistics to assess the reliability and validity of web-enabled mechanistic case diagrams (MCDs) as a potential tool to assess students' ability to integrate basic science and clinical information. Students review a narrative clinical case and construct an MCD using items provided by the case author. Students identify the relationships among underlying risk factors, etiology, pathogenesis and pathophysiology, and the patients' signs and symptoms. They receive one point for each correctly-identified link. In 2014-15 and 2015-16, case diagrams were implemented in consecutive classes of 150 medical students. The alpha reliability coefficient for the overall score, constructed using each student's mean proportion correct across all cases, was 0.82. Discrimination indices for each of the case scores with the overall score ranged from 0.23 to 0.51. In a G study using those students with complete data (n = 251) on all 16 cases, 10% of the variance was true score variance, and systematic case variance was large. Using 16 cases generated a G coefficient (relative score reliability) equal to .72 and a Phi equal to .65. The next phase of the project will involve deploying MCDs in higher-stakes settings to determine whether similar results can be achieved. Further analyses will determine whether these assessments correlate with other measures of higher-order thinking skills.

Case file coding of child maltreatment: Methods, challenges, and innovations in a longitudinal project of youth in foster care.

PubMed

Huffhines, Lindsay; Tunno, Angela M; Cho, Bridget; Hambrick, Erin P; Campos, Ilse; Lichty, Brittany; Jackson, Yo

2016-08-01

State social service agency case files are a common mechanism for obtaining information about a child's maltreatment history, yet these documents are often challenging for researchers to access, and then to process in a manner consistent with the requirements of social science research designs. Specifically, accessing and navigating case files is an extensive undertaking, and a task that many researchers have had to maneuver with little guidance. Even after the files are in hand and the research questions and relevant variables have been clarified, case file information about a child's maltreatment exposure can be idiosyncratic, vague, inconsistent, and incomplete, making coding such information into useful variables for statistical analyses difficult. The Modified Maltreatment Classification System (MMCS) is a popular tool used to guide the process, and though comprehensive, this coding system cannot cover all idiosyncrasies found in case files. It is not clear from the literature how researchers implement this system while accounting for issues outside of the purview of the MMCS or that arise during MMCS use. Finally, a large yet reliable file coding team is essential to the process, however, the literature lacks training guidelines and methods for establishing reliability between coders. In an effort to move the field toward a common approach, the purpose of the present discussion is to detail the process used by one large-scale study of child maltreatment, the Studying Pathways to Adjustment and Resilience in Kids (SPARK) project, a longitudinal study of resilience in youth in foster care. The article addresses each phase of case file coding, from accessing case files, to identifying how to measure constructs of interest, to dealing with exceptions to the coding system, to coding variables reliably, to training large teams of coders and monitoring for fidelity. Implications for a comprehensive and efficient approach to case file coding are discussed.

Case file coding of child maltreatment: Methods, challenges, and innovations in a longitudinal project of youth in foster care☆

PubMed Central

Huffhines, Lindsay; Tunno, Angela M.; Cho, Bridget; Hambrick, Erin P.; Campos, Ilse; Lichty, Brittany; Jackson, Yo

2016-01-01

State social service agency case files are a common mechanism for obtaining information about a child’s maltreatment history, yet these documents are often challenging for researchers to access, and then to process in a manner consistent with the requirements of social science research designs. Specifically, accessing and navigating case files is an extensive undertaking, and a task that many researchers have had to maneuver with little guidance. Even after the files are in hand and the research questions and relevant variables have been clarified, case file information about a child’s maltreatment exposure can be idiosyncratic, vague, inconsistent, and incomplete, making coding such information into useful variables for statistical analyses difficult. The Modified Maltreatment Classification System (MMCS) is a popular tool used to guide the process, and though comprehensive, this coding system cannot cover all idiosyncrasies found in case files. It is not clear from the literature how researchers implement this system while accounting for issues outside of the purview of the MMCS or that arise during MMCS use. Finally, a large yet reliable file coding team is essential to the process, however, the literature lacks training guidelines and methods for establishing reliability between coders. In an effort to move the field toward a common approach, the purpose of the present discussion is to detail the process used by one large-scale study of child maltreatment, the Studying Pathways to Adjustment and Resilience in Kids (SPARK) project, a longitudinal study of resilience in youth in foster care. The article addresses each phase of case file coding, from accessing case files, to identifying how to measure constructs of interest, to dealing with exceptions to the coding system, to coding variables reliably, to training large teams of coders and monitoring for fidelity. Implications for a comprehensive and efficient approach to case file coding are discussed. PMID:28138207

A Case Study of Childhood Disintegrative Disorder Using Systematic Analysis of Family Home Movies

ERIC Educational Resources Information Center

Palomo, Ruben; Thompson, Meagan; Colombi, Costanza; Cook, Ian; Goldring, Stacy; Young, Gregory S.; Ozonoff, Sally

2008-01-01

Childhood disintegrative disorder (CDD) is a rare pervasive developmental disorder that involves regression after a period of at least 2 years of typical development. This case study presents data from family home movies, coded by reliable raters using an objective coding system, to examine the trajectory of development in one child with a…

The Role of Reliability, Vulnerability and Resilience in the Management of Water Quality Systems

NASA Astrophysics Data System (ADS)

Lence, B. J.; Maier, H. R.

2001-05-01

The risk based performance indicators reliability, vulnerability and resilience provide measures of the frequency, magnitude and duration of the failure of water resources systems, respectively. They have been applied primarily to water supply problems, including the assessment of the performance of reservoirs and water distribution systems. Applications to water quality case studies have been limited, although the need to consider the length and magnitude of violations of a particular water quality standard has been recognized for some time. In this research, the role of reliability, vulnerability and resilience in water quality management applications is investigated by examining their significance as performance measures for water quality systems and assessing their potential for assisting in decision making processes. The importance of each performance indicator is discussed and a framework for classifying such systems, based on the relative significance of each of these indicators, is introduced and illustrated qualitatively with various case studies. Quantitative examples drawn from both lake and river water quality modeling exercises are then provided.

Reliability of the AMA Guides to the Evaluation of Permanent Impairment.

PubMed

Forst, Linda; Friedman, Lee; Chukwu, Abraham

2010-12-01

AMA's Guides to the Evaluation of Permanent Impairment is used to rate loss of function and determine compensation and ability to work after injury or illness; however, there are few studies that evaluate reliability or construct validity. To evaluate the reliability of the fifth and sixth editions for back injury; to determine best methods for further study. Intra-class correlation coefficients within and between raters were relatively high. There was wider variability for individual cases. Impairment ratings were lower and correlated less well for the sixth edition, though confidence intervals overlapped. The sixth edition may not be an improvement over the fifth. A research agenda should include investigations of reliability and construct validity for different body sites and organ systems along the entire rating scale and among different categories of raters.

Reliability of robotic system during general surgical procedures in a university hospital.

PubMed

Buchs, Nicolas C; Pugin, François; Volonté, Francesco; Morel, Philippe

2014-01-01

Data concerning the reliability of robotic systems are scarce, especially for general surgery. The aim of this study was to assess the incidence and consequences of robotic malfunction in a teaching institution. From January 2006 to September 2012, 526 consecutive robotic general surgical procedures were performed. All failures were prospectively recorded in a computerized database and reviewed retrospectively. Robotic malfunctions occurred in 18 cases (3.4%). These dysfunctions concerned the robotic instruments in 9 cases, the robotic arms in 4 cases, the surgical console in 3 cases, and the optical system in 2 cases. Two malfunctions were considered critical, and 1 led to a laparoscopic conversion (conversion rate due to malfunction, .2%). Overall, there were more dysfunctions at the beginning of the study period (2006 to 2010) than more recently (2011 to 2012) (4.2% vs 2.6%, P = .35). The robotic system malfunction rate was low. Most malfunctions could be resolved during surgery, allowing the procedures to be completed safely. With increased experience, the system malfunction rate seems to be reduced. Copyright © 2014 Elsevier Inc. All rights reserved.

Reliability of clinical impact grading by healthcare professionals of common prescribing error and optimisation cases in critical care patients.

PubMed

Bourne, Richard S; Shulman, Rob; Tomlin, Mark; Borthwick, Mark; Berry, Will; Mills, Gary H

2017-04-01

To identify between and within profession-rater reliability of clinical impact grading for common critical care prescribing error and optimisation cases. To identify representative clinical impact grades for each individual case. Electronic questionnaire. 5 UK NHS Trusts. 30 Critical care healthcare professionals (doctors, pharmacists and nurses). Participants graded severity of clinical impact (5-point categorical scale) of 50 error and 55 optimisation cases. Case between and within profession-rater reliability and modal clinical impact grading. Between and within profession rater reliability analysis used linear mixed model and intraclass correlation, respectively. The majority of error and optimisation cases (both 76%) had a modal clinical severity grade of moderate or higher. Error cases: doctors graded clinical impact significantly lower than pharmacists (-0.25; P < 0.001) and nurses (-0.53; P < 0.001), with nurses significantly higher than pharmacists (0.28; P < 0.001). Optimisation cases: doctors graded clinical impact significantly lower than nurses and pharmacists (-0.39 and -0.5; P < 0.001, respectively). Within profession reliability grading was excellent for pharmacists (0.88 and 0.89; P < 0.001) and doctors (0.79 and 0.83; P < 0.001) but only fair to good for nurses (0.43 and 0.74; P < 0.001), for optimisation and error cases, respectively. Representative clinical impact grades for over 100 common prescribing error and optimisation cases are reported for potential clinical practice and research application. The between professional variability highlights the importance of multidisciplinary perspectives in assessment of medication error and optimisation cases in clinical practice and research. © The Author 2017. Published by Oxford University Press in association with the International Society for Quality in Health Care. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Network challenges for cyber physical systems with tiny wireless devices: a case study on reliable pipeline condition monitoring.

PubMed

Ali, Salman; Qaisar, Saad Bin; Saeed, Husnain; Khan, Muhammad Farhan; Naeem, Muhammad; Anpalagan, Alagan

2015-03-25

The synergy of computational and physical network components leading to the Internet of Things, Data and Services has been made feasible by the use of Cyber Physical Systems (CPSs). CPS engineering promises to impact system condition monitoring for a diverse range of fields from healthcare, manufacturing, and transportation to aerospace and warfare. CPS for environment monitoring applications completely transforms human-to-human, human-to-machine and machine-to-machine interactions with the use of Internet Cloud. A recent trend is to gain assistance from mergers between virtual networking and physical actuation to reliably perform all conventional and complex sensing and communication tasks. Oil and gas pipeline monitoring provides a novel example of the benefits of CPS, providing a reliable remote monitoring platform to leverage environment, strategic and economic benefits. In this paper, we evaluate the applications and technical requirements for seamlessly integrating CPS with sensor network plane from a reliability perspective and review the strategies for communicating information between remote monitoring sites and the widely deployed sensor nodes. Related challenges and issues in network architecture design and relevant protocols are also provided with classification. This is supported by a case study on implementing reliable monitoring of oil and gas pipeline installations. Network parameters like node-discovery, node-mobility, data security, link connectivity, data aggregation, information knowledge discovery and quality of service provisioning have been reviewed.

Network Challenges for Cyber Physical Systems with Tiny Wireless Devices: A Case Study on Reliable Pipeline Condition Monitoring

PubMed Central

Ali, Salman; Qaisar, Saad Bin; Saeed, Husnain; Farhan Khan, Muhammad; Naeem, Muhammad; Anpalagan, Alagan

2015-01-01

The synergy of computational and physical network components leading to the Internet of Things, Data and Services has been made feasible by the use of Cyber Physical Systems (CPSs). CPS engineering promises to impact system condition monitoring for a diverse range of fields from healthcare, manufacturing, and transportation to aerospace and warfare. CPS for environment monitoring applications completely transforms human-to-human, human-to-machine and machine-to-machine interactions with the use of Internet Cloud. A recent trend is to gain assistance from mergers between virtual networking and physical actuation to reliably perform all conventional and complex sensing and communication tasks. Oil and gas pipeline monitoring provides a novel example of the benefits of CPS, providing a reliable remote monitoring platform to leverage environment, strategic and economic benefits. In this paper, we evaluate the applications and technical requirements for seamlessly integrating CPS with sensor network plane from a reliability perspective and review the strategies for communicating information between remote monitoring sites and the widely deployed sensor nodes. Related challenges and issues in network architecture design and relevant protocols are also provided with classification. This is supported by a case study on implementing reliable monitoring of oil and gas pipeline installations. Network parameters like node-discovery, node-mobility, data security, link connectivity, data aggregation, information knowledge discovery and quality of service provisioning have been reviewed. PMID:25815444

Modelling utility-scale wind power plants. Part 1: Economics

NASA Astrophysics Data System (ADS)

Milligan, Michael R.

1999-10-01

As the worldwide use of wind turbine generators continues to increase in utility-scale applications, it will become increasingly important to assess the economic and reliability impact of these intermittent resources. Although the utility industry in the United States appears to be moving towards a restructured environment, basic economic and reliability issues will continue to be relevant to companies involved with electricity generation. This article is the first of two which address modelling approaches and results obtained in several case studies and research projects at the National Renewable Energy Laboratory (NREL). This first article addresses the basic economic issues associated with electricity production from several generators that include large-scale wind power plants. An important part of this discussion is the role of unit commitment and economic dispatch in production cost models. This paper includes overviews and comparisons of the prevalent production cost modelling methods, including several case studies applied to a variety of electric utilities. The second article discusses various methods of assessing capacity credit and results from several reliability-based studies performed at NREL.

An Interprofessional Program Evaluation Case Study: Utilizing Multiple Measures To Assess What Matters. AIR 1997 Annual Forum Paper.

ERIC Educational Resources Information Center

Delaney, Anne Marie

This paper reviews the first two years of a model program-evaluation case study which is intended to show: (1) how program evaluation can contribute to academic and professional degree programs; (2) how qualitative and quantitative techniques can be used to produce reliable measures for evaluation studies; and (3) how the role of the institutional…

MEASUREMENT: ACCOUNTING FOR RELIABILITY IN PERFORMANCE ESTIMATES.

PubMed

Waterman, Brian; Sutter, Robert; Burroughs, Thomas; Dunagan, W Claiborne

2014-01-01

When evaluating physician performance measures, physician leaders are faced with the quandary of determining whether departures from expected physician performance measurements represent a true signal or random error. This uncertainty impedes the physician leader's ability and confidence to take appropriate performance improvement actions based on physician performance measurements. Incorporating reliability adjustment into physician performance measurement is a valuable way of reducing the impact of random error in the measurements, such as those caused by small sample sizes. Consequently, the physician executive has more confidence that the results represent true performance and is positioned to make better physician performance improvement decisions. Applying reliability adjustment to physician-level performance data is relatively new. As others have noted previously, it's important to keep in mind that reliability adjustment adds significant complexity to the production, interpretation and utilization of results. Furthermore, the methods explored in this case study only scratch the surface of the range of available Bayesian methods that can be used for reliability adjustment; further study is needed to test and compare these methods in practice and to examine important extensions for handling specialty-specific concerns (e.g., average case volumes, which have been shown to be important in cardiac surgery outcomes). Moreover, it's important to note that the provider group average as a basis for shrinkage is one of several possible choices that could be employed in practice and deserves further exploration in future research. With these caveats, our results demonstrate that incorporating reliability adjustment into physician performance measurements is feasible and can notably reduce the incidence of "real" signals relative to what one would expect to see using more traditional approaches. A physician leader who is interested in catalyzing performance improvement through focused, effective physician performance improvement is well advised to consider the value of incorporating reliability adjustments into their performance measurement system.

Interrater reliability of the injury reporting of the injury surveillance system used in international athletics championships.

PubMed

Edouard, Pascal; Junge, Astrid; Kiss-Polauf, Marianna; Ramirez, Christophe; Sousa, Monica; Timpka, Toomas; Branco, Pedro

2018-03-01

The quality of epidemiological injury data depends on the reliability of reporting to an injury surveillance system. Ascertaining whether all physicians/physiotherapists report the same information for the same injury case is of major interest to determine data validity. The aim of this study was therefore to analyse the data collection reliability through the analysis of the interrater reliability. Cross-sectional survey. During the 2016 European Athletics Advanced Athletics Medicine Course in Amsterdam, all national medical teams were asked to complete seven virtual case reports on a standardised injury report form using the same definitions and classifications of injuries as the international athletics championships injury surveillance protocol. The completeness of data and the Fleiss' kappa coefficients for the inter-rater reliability were calculated for: sex, age, event, circumstance, location, type, assumed cause and estimated time-loss. Forty-one team physicians and physiotherapists of national medical teams participated in the study (response rate 89.1%). Data completeness was 96.9%. The Fleiss' kappa coefficients were: almost perfect for sex (k=1), injury location (k=0.991), event (k=0.953), circumstance (k=0.942), and age (k=0.870), moderate for type (k=0.507), fair for assumed cause (k=0.394), and poor for estimated time-loss (k=0.155). The injury surveillance system used during international athletics championships provided reliable data for "sex", "location", "event", "circumstance", and "age". More caution should be taken for "assumed cause" and "type", and even more for "estimated time-loss". This injury surveillance system displays satisfactory data quality (reliable data and high data completeness), and thus, can be recommended as tool to collect epidemiology information on injuries during international athletics championships. Copyright © 2018 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

A biopsychosocial vignette for case conceptualization in dementia (VIG-Dem): development and pilot study.

PubMed

Spector, Aimee; Hebditch, Molly; Stoner, Charlotte R; Gibbor, Luke

2016-09-01

The ability to identify biological, social, and psychological issues for people with dementia is an important skill for healthcare professionals. Therefore, valid and reliable measures are needed to assess this ability. This study involves the development of a vignette style measure to capture the extent to which health professionals use "Biopsychosocial" thinking in dementia care (VIG-Dem), based on the framework of the model developed by Spector and Orrell (2010). The development process consisted of Phase 1: Developing and refining the vignettes; Phase 2: Field testing (N = 9), and Phase 3: A pilot study to assess reliability and validity (N = 131). The VIG-Dem, consisting of two vignettes with open-ended questions and a standardized scoring scheme, was developed. Evidence for the good inter-rater reliability, convergent validity, and test-retest reliability were established. The VIG-Dem has good psychometric properties and may provide a useful tool in dementia care research and practice.

77 FR 54917 - Findings of Research Misconduct

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-06

... values for inter-observer reliabilities when coding was done by only one observer, in both cases leading... Research Integrity (ORI) has taken final action in the following case: Marc Hauser, Ph.D., Harvard... collaborators that he miscoded some of the trials and that the study failed to provide support for the initial...

Using multivariate regression modeling for sampling and predicting chemical characteristics of mixed waste in old landfills.

PubMed

Brandstätter, Christian; Laner, David; Prantl, Roman; Fellner, Johann

2014-12-01

Municipal solid waste landfills pose a threat on environment and human health, especially old landfills which lack facilities for collection and treatment of landfill gas and leachate. Consequently, missing information about emission flows prevent site-specific environmental risk assessments. To overcome this gap, the combination of waste sampling and analysis with statistical modeling is one option for estimating present and future emission potentials. Optimizing the tradeoff between investigation costs and reliable results requires knowledge about both: the number of samples to be taken and variables to be analyzed. This article aims to identify the optimized number of waste samples and variables in order to predict a larger set of variables. Therefore, we introduce a multivariate linear regression model and tested the applicability by usage of two case studies. Landfill A was used to set up and calibrate the model based on 50 waste samples and twelve variables. The calibrated model was applied to Landfill B including 36 waste samples and twelve variables with four predictor variables. The case study results are twofold: first, the reliable and accurate prediction of the twelve variables can be achieved with the knowledge of four predictor variables (Loi, EC, pH and Cl). For the second Landfill B, only ten full measurements would be needed for a reliable prediction of most response variables. The four predictor variables would exhibit comparably low analytical costs in comparison to the full set of measurements. This cost reduction could be used to increase the number of samples yielding an improved understanding of the spatial waste heterogeneity in landfills. Concluding, the future application of the developed model potentially improves the reliability of predicted emission potentials. The model could become a standard screening tool for old landfills if its applicability and reliability would be tested in additional case studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

Seeking high reliability in primary care: Leadership, tools, and organization.

PubMed

Weaver, Robert R

2015-01-01

Leaders in health care increasingly recognize that improving health care quality and safety requires developing an organizational culture that fosters high reliability and continuous process improvement. For various reasons, a reliability-seeking culture is lacking in most health care settings. Developing a reliability-seeking culture requires leaders' sustained commitment to reliability principles using key mechanisms to embed those principles widely in the organization. The aim of this study was to examine how key mechanisms used by a primary care practice (PCP) might foster a reliability-seeking, system-oriented organizational culture. A case study approach was used to investigate the PCP's reliability culture. The study examined four cultural artifacts used to embed reliability-seeking principles across the organization: leadership statements, decision support tools, and two organizational processes. To decipher their effects on reliability, the study relied on observations of work patterns and the tools' use, interactions during morning huddles and process improvement meetings, interviews with clinical and office staff, and a "collective mindfulness" questionnaire. The five reliability principles framed the data analysis. Leadership statements articulated principles that oriented the PCP toward a reliability-seeking culture of care. Reliability principles became embedded in the everyday discourse and actions through the use of "problem knowledge coupler" decision support tools and daily "huddles." Practitioners and staff were encouraged to report unexpected events or close calls that arose and which often initiated a formal "process change" used to adjust routines and prevent adverse events from recurring. Activities that foster reliable patient care became part of the taken-for-granted routine at the PCP. The analysis illustrates the role leadership, tools, and organizational processes play in developing and embedding a reliable-seeking culture across an organization. Progress toward a reliability-seeking, system-oriented approach to care remains ongoing, and movement in that direction requires deliberate and sustained effort by committed leaders in health care.

Reliable and valid assessment of point-of-care ultrasonography.

PubMed

Todsen, Tobias; Tolsgaard, Martin Grønnebæk; Olsen, Beth Härstedt; Henriksen, Birthe Merete; Hillingsø, Jens Georg; Konge, Lars; Jensen, Morten Lind; Ringsted, Charlotte

2015-02-01

To explore the reliability and validity of the Objective Structured Assessment of Ultrasound Skills (OSAUS) scale for point-of-care ultrasonography (POC US) performance. POC US is increasingly used by clinicians and is an essential part of the management of acute surgical conditions. However, the quality of performance is highly operator-dependent. Therefore, reliable and valid assessment of trainees' ultrasonography competence is needed to ensure patient safety. Twenty-four physicians, representing novices, intermediates, and experts in POC US, scanned 4 different surgical patient cases in a controlled set-up. All ultrasound examinations were video-recorded and assessed by 2 blinded radiologists using OSAUS. Reliability was examined using generalizability theory. Construct validity was examined by comparing performance scores between the groups and by correlating physicians' OSAUS scores with diagnostic accuracy. The generalizability coefficient was high (0.81) and a D-study demonstrated that 1 assessor and 5 cases would result in similar reliability. The construct validity of the OSAUS scale was supported by a significant difference in the mean scores between the novice group (17.0; SD 8.4) and the intermediate group (30.0; SD 10.1), P = 0.007, as well as between the intermediate group and the expert group (72.9; SD 4.4), P = 0.04, and by a high correlation between OSAUS scores and diagnostic accuracy (Spearman ρ correlation coefficient = 0.76; P < 0.001). This study demonstrates high reliability as well as evidence of construct validity of the OSAUS scale for assessment of POC US competence. Hence, the OSAUS scale may be suitable for both in-training as well as end-of-training assessment.

Implementing the undergraduate mini-CEX: a tailored approach at Southampton University.

PubMed

Hill, Faith; Kendall, Kathleen; Galbraith, Kevin; Crossley, Jim

2009-04-01

The mini-clinical evaluation exercise (mini-CEX) is widely used in the UK to assess clinical competence, but there is little evidence regarding its implementation in the undergraduate setting. This study aimed to estimate the validity and reliability of the undergraduate mini-CEX and discuss the challenges involved in its implementation. A total of 3499 mini-CEX forms were completed. Validity was assessed by estimating associations between mini-CEX score and a number of external variables, examining the internal structure of the instrument, checking competency domain response rates and profiles against expectations, and by qualitative evaluation of stakeholder interviews. Reliability was evaluated by overall reliability coefficient (R), estimation of the standard error of measurement (SEM), and from stakeholders' perceptions. Variance component analysis examined the contribution of relevant factors to students' scores. Validity was threatened by various confounding variables, including: examiner status; case complexity; attachment specialty; patient gender, and case focus. Factor analysis suggested that competency domains reflect a single latent variable. Maximum reliability can be achieved by aggregating scores over 15 encounters (R = 0.73; 95% confidence interval [CI] +/- 0.28 based on a 6-point assessment scale). Examiner stringency contributed 29% of score variation and student attachment aptitude 13%. Stakeholder interviews revealed staff development needs but the majority perceived the mini-CEX as more reliable and valid than the previous long case. The mini-CEX has good overall utility for assessing aspects of the clinical encounter in an undergraduate setting. Strengths include fidelity, wide sampling, perceived validity, and formative observation and feedback. Reliability is limited by variable examiner stringency, and validity by confounding variables, but these should be viewed within the context of overall assessment strategies.

Validity and reliability of chronic tic disorder and obsessive-compulsive disorder diagnoses in the Swedish National Patient Register.

PubMed

Rück, Christian; Larsson, K Johan; Lind, Kristina; Perez-Vigil, Ana; Isomura, Kayoko; Sariaslan, Amir; Lichtenstein, Paul; Mataix-Cols, David

2015-06-22

The usefulness of cases diagnosed in administrative registers for research purposes is dependent on diagnostic validity. This study aimed to investigate the validity and inter-rater reliability of recorded diagnoses of tic disorders and obsessive-compulsive disorder (OCD) in the Swedish National Patient Register (NPR). Chart review of randomly selected register cases and controls. 100 tic disorder cases and 100 OCD cases were randomly selected from the NPR based on codes from the International Classification of Diseases (ICD) 8th, 9th and 10th editions, together with 50 epilepsy and 50 depression control cases. The obtained psychiatric records were blindly assessed by 2 senior psychiatrists according to the criteria of the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) and ICD-10. Positive predictive value (PPV; cases diagnosed correctly divided by the sum of true positives and false positives). Between 1969 and 2009, the NPR included 7286 tic disorder and 24,757 OCD cases. The vast majority (91.3% of tic cases and 80.1% of OCD cases) are coded with the most recent ICD version (ICD-10). For tic disorders, the PPV was high across all ICD versions (PPV=89% in ICD-8, 86% in ICD-9 and 97% in ICD-10). For OCD, only ICD-10 codes had high validity (PPV=91-96%). None of the epilepsy or depression control cases were wrongly diagnosed as having tic disorders or OCD, respectively. Inter-rater reliability was outstanding for both tic disorders (κ=1) and OCD (κ=0.98). The validity and reliability of ICD codes for tic disorders and OCD in the Swedish NPR is generally high. We propose simple algorithms to further increase the confidence in the validity of these codes for epidemiological research. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Assessing clinical competency in the health sciences

NASA Astrophysics Data System (ADS)

Panzarella, Karen Joanne

To test the success of integrated curricula in schools of health sciences, meaningful measurements of student performance are required to assess clinical competency. This research project analyzed a new performance assessment tool, the Integrated Standardized Patient Examination (ISPE), for assessing clinical competency: specifically, to assess Doctor of Physical Therapy (DPT) students' clinical competence as the ability to integrate basic science knowledge with clinical communication skills. Thirty-four DPT students performed two ISPE cases, one of a patient who sustained a stroke and the other a patient with a herniated lumbar disc. Cases were portrayed by standardized patients (SPs) in a simulated clinical setting. Each case was scored by an expert evaluator in the exam room and then by one investigator and the students themselves via videotape. The SPs scored each student on an overall encounter rubric. Written feedback was obtained from all participants in the study. Acceptable reliability was demonstrated via inter-rater agreement as well as inter-rater correlations on items that used a dichotomous scale, whereas the items requiring the use of the 4-point rubric were somewhat less reliable. For the entire scale both cases had a significant correlation between the Expert-Investigator pair of raters, for the CVA case r = .547, p < .05 and for the HD case r = .700, p < .01. The SPs scored students higher than the other raters. Students' self-assessments were most closely aligned with the investigator. Effects were apparent due to case. Content validity was gathered in the process of developing cases and patient scenarios that were used in this study. Construct validity was obtained from the survey results analyzed from the experts and students. Future studies should examine the effect of rater training upon the reliability. Criterion or predictive validity could be further studied by comparing students' performances on the ISPE with other independent estimates of students' competence. The unique integration questions of the ISPE were judged to have good content validity from experts and students, suggestive that integration, a most crucial element of clinical competence, while done in the mind of the student, can be practiced, learned and assessed.

Assessing the reliability of ecotoxicological studies: An overview of current needs and approaches.

PubMed

Moermond, Caroline; Beasley, Amy; Breton, Roger; Junghans, Marion; Laskowski, Ryszard; Solomon, Keith; Zahner, Holly

2017-07-01

In general, reliable studies are well designed and well performed, and enough details on study design and performance are reported to assess the study. For hazard and risk assessment in various legal frameworks, many different types of ecotoxicity studies need to be evaluated for reliability. These studies vary in study design, methodology, quality, and level of detail reported (e.g., reviews, peer-reviewed research papers, or industry-sponsored studies documented under Good Laboratory Practice [GLP] guidelines). Regulators have the responsibility to make sound and verifiable decisions and should evaluate each study for reliability in accordance with scientific principles regardless of whether they were conducted in accordance with GLP and/or standardized methods. Thus, a systematic and transparent approach is needed to evaluate studies for reliability. In this paper, 8 different methods for reliability assessment were compared using a number of attributes: categorical versus numerical scoring methods, use of exclusion and critical criteria, weighting of criteria, whether methods are tested with case studies, domain of applicability, bias toward GLP studies, incorporation of standard guidelines in the evaluation method, number of criteria used, type of criteria considered, and availability of guidance material. Finally, some considerations are given on how to choose a suitable method for assessing reliability of ecotoxicity studies. Integr Environ Assess Manag 2017;13:640-651. © 2016 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC). © 2016 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Reliability of Causality Assessment for Drug, Herbal and Dietary Supplement Hepatoxicity in the Drug-Induced Liver Injury Network (DILIN)

PubMed Central

Hayashi, Paul H.; Barnhart, Huiman X.; Fontana, Robert J.; Chalasani, Naga; Davern, Timothy J.; Talwalkar, Jayant A.; Reddy, K. Rajender; Stolz, Andrew A.; Hoofnagle, Jay H.; Rockey, Don C.

2014-01-01

Background Due to the lack of objective tests to diagnose drug induced liver injury (DILI), causality assessment is a matter of debate. Expert opinion is often used in research and industry but its test-retest reliability is unknown. Aims To determine the test-retest reliability of the expert opinion process used by the Drug-Induced Liver Injury Network (DILIN) Methods Three DILIN hepatologists adjudicate suspected hepatotoxicity cases to 1 of 5 categories representing levels of likelihood of DILI. Adjudication is based on retrospective assessment of gathered case data that includes prospective follow-up information. One hundred randomly selected DILIN cases were re-assessed using the same processes for initial assessment but by 3 different reviewers in 92% of cases. Results The median time between assessments was 938 days (range: 140–2352). Thirty-one cases involved >1 agent. Weighted kappa statistics for overall case and individual agent category agreement were 0.60 (95% CI: 0.50–0.71) and 0.60 (0.52–0.68), respectively. Overall case adjudications were within one category of each other 93% of the time, while 5% differed by 2 categories and 2% differed by 3 categories. Fourteen-percent crossed the 50% threshold of likelihood due to competing diagnoses or atypical timing between drug exposure and injury. Conclusions The DILIN expert opinion causality assessment method has moderate inter-observer reliability but very good agreement within 1 category. A small but important proportion of cases could not be reliably diagnosed as ≥ 50% likely to be DILI. PMID:24661785

Reliability analysis and utilization of PEMs in space application

NASA Astrophysics Data System (ADS)

Jiang, Xiujie; Wang, Zhihua; Sun, Huixian; Chen, Xiaomin; Zhao, Tianlin; Yu, Guanghua; Zhou, Changyi

2009-11-01

More and more plastic encapsulated microcircuits (PEMs) are used in space missions to achieve high performance. Since PEMs are designed for use in terrestrial operating conditions, the successful usage of PEMs in space harsh environment is closely related to reliability issues, which should be considered firstly. However, there is no ready-made methodology for PEMs in space applications. This paper discusses the reliability for the usage of PEMs in space. This reliability analysis can be divided into five categories: radiation test, radiation hardness, screening test, reliability calculation and reliability assessment. One case study is also presented to illuminate the details of the process, in which a PEM part is used in a joint space program Double-Star Project between the European Space Agency (ESA) and China. The influence of environmental constrains including radiation, humidity, temperature and mechanics on the PEM part has been considered. Both Double-Star Project satellites are still running well in space now.

Fundamentals of Digital Engineering: Designing for Reliability

NASA Technical Reports Server (NTRS)

Katz, R.; Day, John H. (Technical Monitor)

2001-01-01

The concept of designing for reliability will be introduced along with a brief overview of reliability, redundancy and traditional methods of fault tolerance is presented, as applied to current logic devices. The fundamentals of advanced circuit design and analysis techniques will be the primary focus. The introduction will cover the definitions of key device parameters and how analysis is used to prove circuit correctness. Basic design techniques such as synchronous vs asynchronous design, metastable state resolution time/arbiter design, and finite state machine structure/implementation will be reviewed. Advanced topics will be explored such as skew-tolerant circuit design, the use of triple-modular redundancy and circuit hazards, device transients and preventative circuit design, lock-up states in finite state machines generated by logic synthesizers, device transient characteristics, radiation mitigation techniques. worst-case analysis, the use of timing analyzer and simulators, and others. Case studies and lessons learned from spaceflight designs will be given as examples

Abstracting ICU Nursing Care Quality Data From the Electronic Health Record.

PubMed

Seaman, Jennifer B; Evans, Anna C; Sciulli, Andrea M; Barnato, Amber E; Sereika, Susan M; Happ, Mary Beth

2017-09-01

The electronic health record is a potentially rich source of data for clinical research in the intensive care unit setting. We describe the iterative, multi-step process used to develop and test a data abstraction tool, used for collection of nursing care quality indicators from the electronic health record, for a pragmatic trial. We computed Cohen's kappa coefficient (κ) to assess interrater agreement or reliability of data abstracted using preliminary and finalized tools. In assessing the reliability of study data ( n = 1,440 cases) using the finalized tool, 108 randomly selected cases (10% of first half sample; 5% of last half sample) were independently abstracted by a second rater. We demonstrated mean κ values ranging from 0.61 to 0.99 for all indicators. Nursing care quality data can be accurately and reliably abstracted from the electronic health records of intensive care unit patients using a well-developed data collection tool and detailed training.

Constraining uncertainties in water supply reliability in a tropical data scarce basin

NASA Astrophysics Data System (ADS)

Kaune, Alexander; Werner, Micha; Rodriguez, Erasmo; de Fraiture, Charlotte

2015-04-01

Assessing the water supply reliability in river basins is essential for adequate planning and development of irrigated agriculture and urban water systems. In many cases hydrological models are applied to determine the surface water availability in river basins. However, surface water availability and variability is often not appropriately quantified due to epistemic uncertainties, leading to water supply insecurity. The objective of this research is to determine the water supply reliability in order to support planning and development of irrigated agriculture in a tropical, data scarce environment. The approach proposed uses a simple hydrological model, but explicitly includes model parameter uncertainty. A transboundary river basin in the tropical region of Colombia and Venezuela with an approximately area of 2100 km² was selected as a case study. The Budyko hydrological framework was extended to consider climatological input variability and model parameter uncertainty, and through this the surface water reliability to satisfy the irrigation and urban demand was estimated. This provides a spatial estimate of the water supply reliability across the basin. For the middle basin the reliability was found to be less than 30% for most of the months when the water is extracted from an upstream source. Conversely, the monthly water supply reliability was high (r>98%) in the lower basin irrigation areas when water was withdrawn from a source located further downstream. Including model parameter uncertainty provides a complete estimate of the water supply reliability, but that estimate is influenced by the uncertainty in the model. Reducing the uncertainty in the model through improved data and perhaps improved model structure will improve the estimate of the water supply reliability allowing better planning of irrigated agriculture and dependable water allocation decisions.

The Chinese version of the Child and Adolescent Scale of Environment (CASE-C): validity and reliability for children with disabilities in Taiwan.

PubMed

Kang, Lin-Ju; Yen, Chia-Feng; Bedell, Gary; Simeonsson, Rune J; Liou, Tsan-Hon; Chi, Wen-Chou; Liu, Shu-Wen; Liao, Hua-Fang; Hwang, Ai-Wen

2015-03-01

Measurement of children's participation and environmental factors is a key component of the assessment in the new Disability Evaluation System (DES) in Taiwan. The Child and Adolescent Scale of Environment (CASE) was translated into Traditional Chinese (CASE-C) and used for assessing environmental factors affecting the participation of children and youth with disabilities in the DES. The aim of this study was to validate the CASE-C. Participants were 614 children and youth aged 6.0-17.9 years with disabilities, with the largest condition group comprised of children with intellectual disability (61%). Internal structure, internal consistency, test-retest reliability, convergent validity, and discriminant (known group) validity were examined using exploratory factor analyses, Cronbach's α coefficient, intra-class correlation coefficients (ICC), correlation analyses, and univariate ANOVAs. A three-factor structure (Family/Community Resources, Assistance/Attitude Supports, and Physical Design Access) of the CASE-C was produced with 38% variance explained. The CASE-C had adequate internal consistency (Cronbach's α=.74-.86) and test-retest reliability (ICCs=.73-.90). Children and youth with disabilities who had higher levels of severity of impairment encountered more environmental barriers and those experiencing more environmental problems also had greater restrictions in participation. The CASE-C scores were found to distinguish children on the basis of disability condition and impairment severity, but not on the basis of age or sex. The CASE-C is valid for assessing environmental problems experienced by children and youth with disabilities in Taiwan. Copyright © 2014 Elsevier Ltd. All rights reserved.

Chapter 15: Reliability of Wind Turbines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sheng, Shuangwen; O'Connor, Ryan

The global wind industry has witnessed exciting developments in recent years. The future will be even brighter with further reductions in capital and operation and maintenance costs, which can be accomplished with improved turbine reliability, especially when turbines are installed offshore. One opportunity for the industry to improve wind turbine reliability is through the exploration of reliability engineering life data analysis based on readily available data or maintenance records collected at typical wind plants. If adopted and conducted appropriately, these analyses can quickly save operation and maintenance costs in a potentially impactful manner. This chapter discusses wind turbine reliability bymore » highlighting the methodology of reliability engineering life data analysis. It first briefly discusses fundamentals for wind turbine reliability and the current industry status. Then, the reliability engineering method for life analysis, including data collection, model development, and forecasting, is presented in detail and illustrated through two case studies. The chapter concludes with some remarks on potential opportunities to improve wind turbine reliability. An owner and operator's perspective is taken and mechanical components are used to exemplify the potential benefits of reliability engineering analysis to improve wind turbine reliability and availability.« less

Assessing Competence in Collaborative Case Conceptualization: Development and Preliminary Psychometric Properties of the Collaborative Case Conceptualization Rating Scale (CCC-RS).

PubMed

Kuyken, Willem; Beshai, Shadi; Dudley, Robert; Abel, Anna; Görg, Nora; Gower, Philip; McManus, Freda; Padesky, Christine A

2016-03-01

Case conceptualization is assumed to be an important element in cognitive-behavioural therapy (CBT) because it describes and explains clients' presentations in ways that inform intervention. However, we do not have a good measure of competence in CBT case conceptualization that can be used to guide training and elucidate mechanisms. The current study addresses this gap by describing the development and preliminary psychometric properties of the Collaborative Case Conceptualization - Rating Scale (CCC-RS; Padesky et al., 2011). The CCC-RS was developed in accordance with the model posited by Kuyken et al. (2009). Data for this study (N = 40) were derived from a larger trial (Wiles et al., 2013) with adults suffering from resistant depression. Internal consistency and inter-rater reliability were calculated. Further, and as a partial test of the scale's validity, Pearson's correlation coefficients were obtained for scores on the CCC-RS and key scales from the Cognitive Therapy Scale - Revised (CTS-R; Blackburn et al., 2001). The CCC-RS showed excellent internal consistency (α = .94), split-half (.82) and inter-rater reliabilities (ICC =.84). Total scores on the CCC-RS were significantly correlated with scores on the CTS-R (r = .54, p < .01). Moreover, the Collaboration subscale of the CCC-RS was significantly correlated (r = .44) with its counterpart of the CTS-R in a theoretically predictable manner. These preliminary results indicate that the CCC-RS is a reliable measure with adequate face, content and convergent validity. Further research is needed to replicate and extend the current findings to other facets of validity.

How reliable are forensic evaluations of legal sanity?

PubMed

Gowensmith, W Neil; Murrie, Daniel C; Boccaccini, Marcus T

2013-04-01

When different clinicians evaluate the same criminal defendant's legal sanity, do they reach the same conclusion? Because Hawaii law requires multiple, independent evaluations when questions about legal sanity arise, Hawaii allows for the first contemporary study of the reliability of legal sanity opinions in routine practice in the United States. We examined 483 evaluation reports, addressing 165 criminal defendants, in which up to three forensic psychiatrists or psychologists offered independent opinions on a defendant's legal sanity. Evaluators reached unanimous agreement regarding legal sanity in only 55.1% of cases. Evaluators tended to disagree more often when a defendant was under the influence of drugs or alcohol at the time of the offense. But evaluators tended to agree more often when they agreed about diagnosing a psychotic disorder, or when the defendant had been psychiatrically hospitalized shortly before the offense. In court, judges followed the majority opinion among evaluators in 91% of cases. But when judges disagreed with the majority opinion, they usually did so to find defendants legally sane, rather than insane. Overall, this study indicates that reliability among practicing forensic evaluators addressing legal sanity may be poorer than the field has tended to assume. Although agreement appears more likely in some cases than others, the frequent disagreements suggest a need for improved training and practice.

Development and testing of a tool for assessing and resolving medication-related problems in older adults in an ambulatory care setting: the individualized medication assessment and planning (iMAP) tool.

PubMed

Crisp, Ginny D; Burkhart, Jena Ivey; Esserman, Denise A; Weinberger, Morris; Roth, Mary T

2011-12-01

Medication is one of the most important interventions for improving the health of older adults, yet it has great potential for causing harm. Clinical pharmacists are well positioned to engage in medication assessment and planning. The Individualized Medication Assessment and Planning (iMAP) tool was developed to aid clinical pharmacists in documenting medication-related problems (MRPs) and associated recommendations. The purpose of our study was to assess the reliability and usability of the iMAP tool in classifying MRPs and associated recommendations in older adults in the ambulatory care setting. Three cases, representative of older adults seen in an outpatient setting, were developed. Pilot testing was conducted and a "gold standard" key developed. Eight eligible pharmacists consented to participate in the study. They were instructed to read each case, make an assessment of MRPs, formulate a plan, and document the information using the iMAP tool. Inter-rater reliability was assessed for each case, comparing the pharmacists' identified MRPs and recommendations to the gold standard. Consistency of categorization across reviewers was assessed using the κ statistic or percent agreement. The mean κ across the 8 pharmacists in classifying MRPs compared with the gold standard was 0.74 (range, 0.54-1.00) for case 1 and 0.68 (range, 0.36-1.00) for case 2, indicating substantial agreement. For case 3, percent agreement was 63% (range, 40%-100%). The mean κ across the 8 pharmacists when classifying recommendations compared with the gold standard was 0.87 (range, 0.58-1.00) for case 1 and 0.88 (range, 0.75-1.00) for case 2, indicating almost perfect agreement. For case 3, percent agreement was 68% (range, 40%-100%). Clinical pharmacists found the iMAP tool easy to use. The iMAP tool provides a reliable and standardized approach for clinical pharmacists to use in the ambulatory care setting to classify MRPs and associated recommendations. Future studies will explore the predictive validity of the tool on clinical outcomes such as health care utilization. Copyright © 2011 Elsevier HS Journals, Inc. All rights reserved.

Selecting statistical model and optimum maintenance policy: a case study of hydraulic pump.

PubMed

Ruhi, S; Karim, M R

2016-01-01

Proper maintenance policy can play a vital role for effective investigation of product reliability. Every engineered object such as product, plant or infrastructure needs preventive and corrective maintenance. In this paper we look at a real case study. It deals with the maintenance of hydraulic pumps used in excavators by a mining company. We obtain the data that the owner had collected and carry out an analysis and building models for pump failures. The data consist of both failure and censored lifetimes of the hydraulic pump. Different competitive mixture models are applied to analyze a set of maintenance data of a hydraulic pump. Various characteristics of the mixture models, such as the cumulative distribution function, reliability function, mean time to failure, etc. are estimated to assess the reliability of the pump. Akaike Information Criterion, adjusted Anderson-Darling test statistic, Kolmogrov-Smirnov test statistic and root mean square error are considered to select the suitable models among a set of competitive models. The maximum likelihood estimation method via the EM algorithm is applied mainly for estimating the parameters of the models and reliability related quantities. In this study, it is found that a threefold mixture model (Weibull-Normal-Exponential) fits well for the hydraulic pump failures data set. This paper also illustrates how a suitable statistical model can be applied to estimate the optimum maintenance period at a minimum cost of a hydraulic pump.

Use of Model-Based Design Methods for Enhancing Resiliency Analysis of Unmanned Aerial Vehicles

NASA Astrophysics Data System (ADS)

Knox, Lenora A.

The most common traditional non-functional requirement analysis is reliability. With systems becoming more complex, networked, and adaptive to environmental uncertainties, system resiliency has recently become the non-functional requirement analysis of choice. Analysis of system resiliency has challenges; which include, defining resilience for domain areas, identifying resilience metrics, determining resilience modeling strategies, and understanding how to best integrate the concepts of risk and reliability into resiliency. Formal methods that integrate all of these concepts do not currently exist in specific domain areas. Leveraging RAMSoS, a model-based reliability analysis methodology for Systems of Systems (SoS), we propose an extension that accounts for resiliency analysis through evaluation of mission performance, risk, and cost using multi-criteria decision-making (MCDM) modeling and design trade study variability modeling evaluation techniques. This proposed methodology, coined RAMSoS-RESIL, is applied to a case study in the multi-agent unmanned aerial vehicle (UAV) domain to investigate the potential benefits of a mission architecture where functionality to complete a mission is disseminated across multiple UAVs (distributed) opposed to being contained in a single UAV (monolithic). The case study based research demonstrates proof of concept for the proposed model-based technique and provides sufficient preliminary evidence to conclude which architectural design (distributed vs. monolithic) is most resilient based on insight into mission resilience performance, risk, and cost in addition to the traditional analysis of reliability.

Scaled CMOS Technology Reliability Users Guide

NASA Technical Reports Server (NTRS)

White, Mark

2010-01-01

The desire to assess the reliability of emerging scaled microelectronics technologies through faster reliability trials and more accurate acceleration models is the precursor for further research and experimentation in this relevant field. The effect of semiconductor scaling on microelectronics product reliability is an important aspect to the high reliability application user. From the perspective of a customer or user, who in many cases must deal with very limited, if any, manufacturer's reliability data to assess the product for a highly-reliable application, product-level testing is critical in the characterization and reliability assessment of advanced nanometer semiconductor scaling effects on microelectronics reliability. A methodology on how to accomplish this and techniques for deriving the expected product-level reliability on commercial memory products are provided.Competing mechanism theory and the multiple failure mechanism model are applied to the experimental results of scaled SDRAM products. Accelerated stress testing at multiple conditions is applied at the product level of several scaled memory products to assess the performance degradation and product reliability. Acceleration models are derived for each case. For several scaled SDRAM products, retention time degradation is studied and two distinct soft error populations are observed with each technology generation: early breakdown, characterized by randomly distributed weak bits with Weibull slope (beta)=1, and a main population breakdown with an increasing failure rate. Retention time soft error rates are calculated and a multiple failure mechanism acceleration model with parameters is derived for each technology. Defect densities are calculated and reflect a decreasing trend in the percentage of random defective bits for each successive product generation. A normalized soft error failure rate of the memory data retention time in FIT/Gb and FIT/cm2 for several scaled SDRAM generations is presented revealing a power relationship. General models describing the soft error rates across scaled product generations are presented. The analysis methodology may be applied to other scaled microelectronic products and their key parameters.

The (un)reliability of item-level semantic priming effects.

PubMed

Heyman, Tom; Bruninx, Anke; Hutchison, Keith A; Storms, Gert

2018-04-05

Many researchers have tried to predict semantic priming effects using a myriad of variables (e.g., prime-target associative strength or co-occurrence frequency). The idea is that relatedness varies across prime-target pairs, which should be reflected in the size of the priming effect (e.g., cat should prime dog more than animal does). However, it is only insightful to predict item-level priming effects if they can be measured reliably. Thus, in the present study we examined the split-half and test-retest reliabilities of item-level priming effects under conditions that should discourage the use of strategies. The resulting priming effects proved extremely unreliable, and reanalyses of three published priming datasets revealed similar cases of low reliability. These results imply that previous attempts to predict semantic priming were unlikely to be successful. However, one study with an unusually large sample size yielded more favorable reliability estimates, suggesting that big data, in terms of items and participants, should be the future for semantic priming research.

Psychometric instrumentation: reliability and validity of instruments used for clinical practice, evidence-based practice projects and research studies.

PubMed

Mayo, Ann M

2015-01-01

It is important for CNSs and other APNs to consider the reliability and validity of instruments chosen for clinical practice, evidence-based practice projects, or research studies. Psychometric testing uses specific research methods to evaluate the amount of error associated with any particular instrument. Reliability estimates explain more about how well the instrument is designed, whereas validity estimates explain more about scores that are produced by the instrument. An instrument may be architecturally sound overall (reliable), but the same instrument may not be valid. For example, if a specific group does not understand certain well-constructed items, then the instrument does not produce valid scores when used with that group. Many instrument developers may conduct reliability testing only once, yet continue validity testing in different populations over many years. All CNSs should be advocating for the use of reliable instruments that produce valid results. Clinical nurse specialists may find themselves in situations where reliability and validity estimates for some instruments that are being utilized are unknown. In such cases, CNSs should engage key stakeholders to sponsor nursing researchers to pursue this most important work.

Great apes are sensitive to prior reliability of an informant in a gaze following task.

PubMed

Schmid, Benjamin; Karg, Katja; Perner, Josef; Tomasello, Michael

2017-01-01

Social animals frequently rely on information from other individuals. This can be costly in case the other individual is mistaken or even deceptive. Human infants below 4 years of age show proficiency in their reliance on differently reliable informants. They can infer the reliability of an informant from few interactions and use that assessment in later interactions with the same informant in a different context. To explore whether great apes share that ability, in our study we confronted great apes with a reliable or unreliable informant in an object choice task, to see whether that would in a subsequent task affect their gaze following behaviour in response to the same informant. In our study, prior reliability of the informant and habituation during the gaze following task affected both great apes' automatic gaze following response and their more deliberate response of gaze following behind barriers. As habituation is very context specific, it is unlikely that habituation in the reliability task affected the gaze following task. Rather it seems that apes employ a reliability tracking strategy that results in a general avoidance of additional information from an unreliable informant.

We need more replication research - A case for test-retest reliability.

PubMed

Leppink, Jimmie; Pérez-Fuster, Patricia

2017-06-01

Following debates in psychology on the importance of replication research, we have also started to see pleas for a more prominent role for replication research in medical education. To enable replication research, it is of paramount importance to carefully study the reliability of the instruments we use. Cronbach's alpha has been the most widely used estimator of reliability in the field of medical education, notably as some kind of quality label of test or questionnaire scores based on multiple items or of the reliability of assessment across exam stations. However, as this narrative review outlines, Cronbach's alpha or alternative reliability statistics may complement but not replace psychometric methods such as factor analysis. Moreover, multiple-item measurements should be preferred above single-item measurements, and when using single-item measurements, coefficients as Cronbach's alpha should not be interpreted as indicators of the reliability of a single item when that item is administered after fundamentally different activities, such as learning tasks that differ in content. Finally, if we want to follow up on recent pleas for more replication research, we have to start studying the test-retest reliability of the instruments we use.

Locating, characterizing and minimizing sources of error for a paper case-based structured oral examination in a multi-campus clerkship.

PubMed

Kumar, A; Bridgham, R; Potts, M; Gushurst, C; Hamp, M; Passal, D

2001-01-01

To determine consistency of assessment in a new paper case-based structured oral examination in a multi-community pediatrics clerkship, and to identify correctable problems in the administration of examination and assessment process. Nine paper case-based oral examinations were audio-taped. From audio-tapes five community coordinators scored examiner behaviors and graded student performance. Correlations among examiner behaviors scores were examined. Graphs identified grading patterns of evaluators. The effect of exam-giving on evaluators was assessed by t-test. Reliability of grades was calculated and the effect of reducing assessment problems was modeled. Exam-givers differed most in their "teaching-guiding" behavior, and this negatively correlated with student grades. Exam reliability was lowered mainly by evaluator differences in leniency and grading pattern; less important was absence of standardization in cases. While grade reliability was low in early use of the paper case-based oral examination, modeling of plausible effects of training and monitoring for greater uniformity in administration of the examination and assigning scores suggests that more adequate reliabilities can be attained.

I-131 rose bengal excretion test is not dead

DOE Office of Scientific and Technical Information (OSTI.GOV)

Antico, V.F.; Denhartog, P.; Ash, J.M.

1985-03-01

One hundred and thirty I-131 Rose Bengal Excretion Studies (RBI) were performed on 84 patients over nine years. In 90% (56/60) of cases with biliary atresia, the 72-hour RBI was less than or equal to 7%. In only 12.5% (3/24) of cases with neonatal hepatitis was the 72-hour RBI less than or equal to 7%. The accuracy of the test was 91% with a specificity of 88%. Thirty patients later were studied following a Kasai procedure. The RBI test reliably predicted the patency of the anastomosis. The authors conclude that the 72-hour RBI is a reliable test in the diagnosismore » of biliary atresia and in the documentation of biliary patency following surgery, provided adequate care is taken in stool collection and measurement.« less

Energy Policy Case Study - California: Renewables and Distributed Energy Resources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Homer, Juliet S.; Bender, Sadie R.; Weimar, Mark R.

2016-09-19

The purpose of this document is to present a case study of energy policies in California related to power system transformation and renewable and distributed energy resources (DERs). Distributed energy resources represent a broad range of technologies that can significantly impact how much, and when, electricity is demanded from the grid. Key policies and proceedings related to power system transformation and DERs are grouped into the following categories: 1.Policies that support achieving environmental and climate goals 2.Policies that promote deployment of DERs 3.Policies that support reliability and integration of DERs 4.Policies that promote market animation and support customer choice. Majormore » challenges going forward are forecasting and modeling DERs, regulatory and utility business model issues, reliability, valuation and pricing, and data management and sharing.« less

Haemophilus haemolyticus Isolates Causing Clinical Disease

PubMed Central

Wang, Xin; Briere, Elizabeth C.; Katz, Lee S.; Cohn, Amanda C.; Clark, Thomas A.; Messonnier, Nancy E.; Mayer, Leonard W.

2012-01-01

We report seven cases of Haemophilus haemolyticus invasive disease detected in the United States, which were previously misidentified as nontypeable Haemophilus influenzae. All cases had different symptoms and presentations. Our study suggests that a testing scheme that includes reliable PCR assays and standard microbiological methods should be used in order to improve H. haemolyticus identification. PMID:22573587

Haemophilus haemolyticus isolates causing clinical disease.

PubMed

Anderson, Raydel; Wang, Xin; Briere, Elizabeth C; Katz, Lee S; Cohn, Amanda C; Clark, Thomas A; Messonnier, Nancy E; Mayer, Leonard W

2012-07-01

We report seven cases of Haemophilus haemolyticus invasive disease detected in the United States, which were previously misidentified as nontypeable Haemophilus influenzae. All cases had different symptoms and presentations. Our study suggests that a testing scheme that includes reliable PCR assays and standard microbiological methods should be used in order to improve H. haemolyticus identification.

Development and Inter-Rater Reliability of the Liverpool Adverse Drug Reaction Causality Assessment Tool

PubMed Central

Gallagher, Ruairi M.; Kirkham, Jamie J.; Mason, Jennifer R.; Bird, Kim A.; Williamson, Paula R.; Nunn, Anthony J.; Turner, Mark A.; Smyth, Rosalind L.; Pirmohamed, Munir

2011-01-01

Aim To develop and test a new adverse drug reaction (ADR) causality assessment tool (CAT). Methods A comparison between seven assessors of a new CAT, formulated by an expert focus group, compared with the Naranjo CAT in 80 cases from a prospective observational study and 37 published ADR case reports (819 causality assessments in total). Main Outcome Measures Utilisation of causality categories, measure of disagreements, inter-rater reliability (IRR). Results The Liverpool ADR CAT, using 40 cases from an observational study, showed causality categories of 1 unlikely, 62 possible, 92 probable and 125 definite (1, 62, 92, 125) and ‘moderate’ IRR (kappa 0.48), compared to Naranjo (0, 100, 172, 8) with ‘moderate’ IRR (kappa 0.45). In a further 40 cases, the Liverpool tool (0, 66, 81, 133) showed ‘good’ IRR (kappa 0.6) while Naranjo (1, 90, 185, 4) remained ‘moderate’. Conclusion The Liverpool tool assigns the full range of causality categories and shows good IRR. Further assessment by different investigators in different settings is needed to fully assess the utility of this tool. PMID:22194808

Comparison of the Multidetector-row Computed Tomographic Angiography Axial and Coronal Planes' Usefulness for Detecting Thoracodorsal Artery Perforators

PubMed Central

Kim, Jong Gyu

2012-01-01

Background During the planning of a thoracodorsal artery perforator (TDAP) free flap, preoperative multidetector-row computed tomographic (MDCT) angiography is valuable for predicting the locations of perforators. However, CT-based perforator mapping of the thoracodorsal artery is not easy because of its small diameter. Thus, we evaluated 1-mm-thick MDCT images in multiple planes to search for reliable perforators accurately. Methods Between July 2010 and October 2011, 19 consecutive patients (13 males, 6 females) who underwent MDCT prior to TDAP free flap operations were enrolled in this study. Patients ranged in age from 10 to 75 years (mean, 39.3 years). MDCT images were acquired at a thickness of 1 mm in the axial, coronal, and sagittal planes. Results The thoracodorsal artery perforators were detected in all 19 cases. The reliable perforators originating from the descending branch were found in 14 cases, of which 6 had transverse branches. The former were well identified in the coronal view, and the latter in the axial view. The location of the most reliable perforators on MDCT images corresponded well with the surgical findings. Conclusions Though MDCT has been widely used in performing the abdominal perforator free flap for detecting reliable perforating vessels, it is not popular in the TDAP free flap. The results of this study suggest that multiple planes of MDCT may increase the probability of detecting the most reliable perforators, along with decreasing the probability of missing available vessels. PMID:22872839

Characterization of Severe Arterial Phase Respiratory Motion Artifact on Gadoxetate Disodium-Enhanced MRI - Assessment of Interrater Agreement and Reliability.

PubMed

Ringe, Kristina Imeen; Luetkens, Julian A; Fimmers, Rolf; Hammerstingl, Renate Maria; Layer, Günter; Maurer, Martin H; Nähle, Claas Philip; Michalik, Sabine; Reimer, Peter; Schraml, Christina; Schreyer, Andreas G; Stumpp, Patrick; Vogl, Thomas J; Wacker, Frank K; Willinek, Winfried; Kukuk, Guido Mattias

2018-04-01

 To assess the interrater agreement and reliability of experienced abdominal radiologists in the characterization and grading of arterial phase gadoxetate disodium-related respiratory motion artifact on liver MRI.  This prospective multicenter study was initiated by the working group for abdominal imaging within the German Roentgen Society (DRG), and approved by the local IRB of each participating center. 11 board-certified radiologists independently reviewed 40 gadoxetate disodium-enhanced liver MRI datasets. Motion artifacts in the arterial phase were assessed on a 5-point scale. Interrater agreement and reliability were calculated using the intraclass correlation coefficient (ICC) and Kendall coefficient of concordance (W), with p < 0.05 deemed significant.  The ICC for interrater agreement and reliability were 0.983 (CI 0.973 - 0.990) and 0.985 (CI 0.978 - 0.991), respectively (both p < 0.0001), indicating excellent agreement and reliability. Kendall's W for interrater agreement was 0.865. A severe motion artifact, defined as a mean motion score ≥ 4 in the arterial phase was observed in 12 patients. In these specific cases, a motion score ≥ 4 was assigned by all readers in 75 % (n = 9/12 cases).  Differentiation and grading of arterial phase respiratory motion artifact is possible with a high level of inter-/intrarater agreement and interrater reliability, which is crucial for assessing the incidence of this phenomenon in larger multicenter studies.   · Inter- and intrarater agreement for motion artifact scoring is excellent among experienced readers.. · Interrater reliability for motion artifact scoring is excellent among experienced readers.. · Characterization of severe motion artifacts proved feasible in this multicenter study.. · Ringe KI, Luetkens JA, Fimmers R et al. Characterization of Severe Arterial Phase Respiratory Motion Artifact on Gadoxetate Disodium-Enhanced MRI - Assessment of Interrater Agreement and Reliability. Fortschr Röntgenstr 2017; 190: 341 - 347. © Georg Thieme Verlag KG Stuttgart · New York.

Interexaminer reliability in physical examination of patients with low back pain.

PubMed

Strender, L E; Sjöblom, A; Sundell, K; Ludwig, R; Taube, A

1997-04-01

Seventy-one patients with low back pain were examined by two physiotherapists (50 patients) and two physicians (21 patients). The two physiotherapists had worked together for many years, but the two physicians had not. The interexaminer reliability of the clinical tests included in the physical examination was evaluated. To evaluate the interexaminer reliability of clinical tests used in the physical examination of patients with low back pain under ideal circumstances, which was the case for the physiotherapists. Numerous clinical tests are used in the evaluation of patients with low back pain. To reach the correct diagnosis, only tests with an acceptable validity and reliability should be used. Previous studies have mainly shown low reliability. It is important that clinical tests not be rejected because of low reliability caused by differences between examiners in performance of the examination and in their definition of normal results. Two examiners, either two physiotherapists or two physicians, independently examined patients with low back pain. In approximately half of the clinical tests studied, an acceptable reliability was demonstrated. On the basis of the physiotherapists series, the reliability was acceptable for a number of clinical tests that are used in the evaluation of patients with low back pain. The results suggest that clinical tests should be standardized to a much higher degree than they are today.

Are Validity and Reliability "Relevant" in Qualitative Evaluation Research?

ERIC Educational Resources Information Center

Goodwin, Laura D.; Goodwin, William L.

1984-01-01

The views of prominant qualitative methodologists on the appropriateness of validity and reliability estimation for the measurement strategies employed in qualitative evaluations are summarized. A case is made for the relevance of validity and reliability estimation. Definitions of validity and reliability for qualitative measurement are presented…

Validity and reliability of self-reported arthritis: Georgia senior centers, 2000-2001.

PubMed

Bombard, Jennifer M; Powell, Kenneth E; Martin, Linda M; Helmick, Charles G; Wilson, William H

2005-04-01

Arthritis and other rheumatic conditions are a common cause of disability among adults in the United States. Telephone interviews of the state-based Behavioral Risk Factor Surveillance System (BRFSS) are used by states and territories to estimate the prevalence of arthritis. The purpose of this study was to assess the validity and reliability of the 1996-2001 BRFSS arthritis case definition in a senior center population. A total of 487 respondents at selected senior centers in Georgia were surveyed by telephone, evaluated 3 to 4 weeks later by board-certified rheumatologists, and completed a written survey in 2000 to 2001. Using the rheumatologists' summary assessment "Does this person have arthritis or a related condition" as the standard, the sensitivity and specificity of the BRFSS arthritis case definitions were calculated. Reliability for the BRFSS arthritis case definition was also calculated by comparing responses to the telephone survey with responses to a written survey. Sensitivity was 70.8% (95% confidence interval [CI]=65.9-75.6), and the specificity was 70.3% (95% CI=62.9-77.8). The agreement between the telephone and written responses indicating self-reported arthritis was high (kappa=0.68). Analyses were conducted in 2002 to 2004. Self-reported arthritis in the 1996-2001 BRFSS was highly reliable, and moderately sensitive and specific among these senior center participants.

Application of a framework to assess the usefulness of alternative sepsis criteria

PubMed Central

Seymour, Christopher W.; Coopersmith, Craig M.; Deutschman, Clifford S; Gesten, Foster; Klompas, Michael; Levy, Mitchell; Martin, Gregory S.; Osborn, Tiffany M.; Rhee, Chanu; Warren, David; Watson, R. Scott; Angus, Derek C.

2016-01-01

The current definition for sepsis is life-threatening, acute organ dysfunction secondary to a dysregulated host response to infection. Criteria to operationalize this definition can be judged by 6 domains of usefulness (reliability; content, construct and criterion validity, measurement burden, and timeliness). The relative importance of these 6 domains depends on the intended purpose for the criteria (clinical care, basic and clinical research, surveillance, or quality improvement (QI) and audit). For example, criteria for clinical care should have high content and construct validity, timeliness, and low measurement burden to facilitate prompt care. Criteria for surveillance or QI/audit place greater emphasis on reliability across individuals and sites and lower emphasis on timeliness. Criteria for clinical trials require timeliness to ensure prompt enrollment and reasonable reliability but can tolerate high measurement burden. Basic research also tolerates high measurement burden and may not need stability over time. In an illustrative case study, we compared examples of criteria designed for clinical care, surveillance and QI/audit among 396,241 patients admitted to 12 academic and community hospitals in an integrated health system. Case rates differed 4-fold and mortality 3-fold. Predictably, clinical care criteria, which emphasized timeliness and low burden and therefore used vital signs and routine laboratory tests, had the highest case identification with lowest mortality. QI /audit criteria, which emphasized reliability and criterion validity, used discharge information and had the lowest case identification with highest mortality. Using this framework to identify the purpose and apply domains of usefulness can help with the evaluation of existing sepsis diagnostic criteria and provide a roadmap for future work. PMID:26901560

Application of a Framework to Assess the Usefulness of Alternative Sepsis Criteria.

PubMed

Seymour, Christopher W; Coopersmith, Craig M; Deutschman, Clifford S; Gesten, Foster; Klompas, Michael; Levy, Mitchell; Martin, Gregory S; Osborn, Tiffany M; Rhee, Chanu; Warren, David K; Watson, R Scott; Angus, Derek C

2016-03-01

The current definition of sepsis is life-threatening, acute organ dysfunction secondary to a dysregulated host response to infection. Criteria to operationalize this definition can be judged by six domains of usefulness (reliability, content, construct and criterion validity, measurement burden, and timeliness). The relative importance of these six domains depends on the intended purpose for the criteria (clinical care, basic and clinical research, surveillance, or quality improvement [QI] and audit). For example, criteria for clinical care should have high content and construct validity, timeliness, and low measurement burden to facilitate prompt care. Criteria for surveillance or QI/audit place greater emphasis on reliability across individuals and sites and lower emphasis on timeliness. Criteria for clinical trials require timeliness to ensure prompt enrollment and reasonable reliability but can tolerate high measurement burden. Basic research also tolerates high measurement burden and may not need stability over time. In an illustrative case study, we compared examples of criteria designed for clinical care, surveillance and QI/audit among 396,241 patients admitted to 12 academic and community hospitals in an integrated health system. Case rates differed four-fold and mortality three-fold. Predictably, clinical care criteria, which emphasized timeliness and low burden and therefore used vital signs and routine laboratory tests, had the greater case identification with lowest mortality. QI/audit criteria, which emphasized reliability and criterion validity, used discharge information and had the lowest case identification with highest mortality. Using this framework to identify the purpose and apply domains of usefulness can help with the evaluation of existing sepsis diagnostic criteria and provide a roadmap for future work.

Scoping study on trends in the economic value of electricity reliability to the U.S. economy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eto, Joseph; Koomey, Jonathan; Lehman, Bryan

During the past three years, working with more than 150 organizations representing public and private stakeholders, EPRI has developed the Electricity Technology Roadmap. The Roadmap identifies several major strategic challenges that must be successfully addressed to ensure a sustainable future in which electricity continues to play an important role in economic growth. Articulation of these anticipated trends and challenges requires a detailed understanding of the role and importance of reliable electricity in different sectors of the economy. This report is intended to contribute to that understanding by analyzing key aspects of trends in the economic value of electricity reliability inmore » the U.S. economy. We first present a review of recent literature on electricity reliability costs. Next, we describe three distinct end-use approaches for tracking trends in reliability needs: (1) an analysis of the electricity-use requirements of office equipment in different commercial sectors; (2) an examination of the use of aggregate statistical indicators of industrial electricity use and economic activity to identify high reliability-requirement customer market segments; and (3) a case study of cleanrooms, which is a cross-cutting market segment known to have high reliability requirements. Finally, we present insurance industry perspectives on electricity reliability as an example of a financial tool for addressing customers' reliability needs.« less

A reliability and validity study of the Palliative Performance Scale

PubMed Central

Ho, Francis; Lau, Francis; Downing, Michael G; Lesperance, Mary

2008-01-01

Background The Palliative Performance Scale (PPS) was first introduced in1996 as a new tool for measurement of performance status in palliative care. PPS has been used in many countries and has been translated into other languages. Methods This study evaluated the reliability and validity of PPS. A web-based, case scenarios study with a test-retest format was used to determine reliability. Fifty-three participants were recruited and randomly divided into two groups, each evaluating 11 cases at two time points. The validity study was based on the content validation of 15 palliative care experts conducted over telephone interviews, with discussion on five themes: PPS as clinical assessment tool, the usefulness of PPS, PPS scores affecting decision making, the problems in using PPS, and the adequacy of PPS instruction. Results The intraclass correlation coefficients for absolute agreement were 0.959 and 0.964 for Group 1, at Time-1 and Time-2; 0.951 and 0.931 for Group 2, at Time-1 and Time-2 respectively. Results showed that the participants were consistent in their scoring over the two times, with a mean Cohen's kappa of 0.67 for Group 1 and 0.71 for Group 2. In the validity study, all experts agreed that PPS is a valuable clinical assessment tool in palliative care. Many of them have already incorporated PPS as part of their practice standard. Conclusion The results of the reliability study demonstrated that PPS is a reliable tool. The validity study found that most experts did not feel a need to further modify PPS and, only two experts requested that some performance status measures be defined more clearly. Areas of PPS use include prognostication, disease monitoring, care planning, hospital resource allocation, clinical teaching and research. PPS is also a good communication tool between palliative care workers. PMID:18680590

Detection of BRAF mutation in Chinese tumor patients using a highly sensitive antibody immunohistochemistry assay

NASA Astrophysics Data System (ADS)

Qiu, Tian; Lu, Haizhen; Guo, Lei; Huang, Wenting; Ling, Yun; Shan, Ling; Li, Wenbin; Ying, Jianming; Lv, Ning

2015-03-01

BRAF mutations can be found in various solid tumors. But accurate and reliable screening for BRAF mutation that is compatible for clinical application is not yet available. In this study, we used an automated immunohistochemistry (IHC) staining coupled with mouse monoclonal anti-BRAF V600E (VE1) primary antibody to screen the BRAF V600E mutation in 779 tumor cases, including 611 colorectal carcinomas (CRC), 127 papillary thyroid carcinomas (PTC) and 41 malignant melanomas. Among the 779 cases, 150 cases were positive for BRAF (V600E) staining, including 38 (of 611, 6%) CRCs, 102 (of 127, 80%) PTCs and 10 (of 41, 24%) malignant melanomas. Sanger sequencing and real-time PCR confirmed the sensitivity and specificity of IHC staining for the V600E mutation are 100% and 99%, respectively. Therefore, our study demonstrates that the fully automated IHC is a reliable tool to determine BRAF mutation status in CRC, PTC and melanoma and can be used for routine clinical screen.

Improving the Cost Efficiency and Readiness of MC-130 Aircrew Training: A Case Study

DTIC Science & Technology

2015-01-01

51 Jiang, Changbing, "A reliable solver of Euclidean traveling salesman problems with Microsoft excel add-in tools for small-size systems...DisplayPage.aspx?DocType=Reference&ItemId=+++1 343364&Pubabbrev=JAWA 124 Jiang, Changbing, "A Reliable Solver of Euclidean Traveling Salesman Problems with...49 Figure 4.5 Training Resources Locations Traveling Salesperson Problem In order to participate in training, aircrews must fly to the

Unique reliability characteristics of fully depleted silicon-on-insulator tunneling FET

NASA Astrophysics Data System (ADS)

Kang, Soo Cheol; Lim, Donghwan; Lim, Sung Kwan; Noh, Jinwoo; Kim, Seung-Mo; Lee, Sang Kyung; Choi, Changhwan; Lee, Byoung Hun

2018-04-01

This study investigated the unique reliability characteristics of tunneling field effect transistors (TFETs) by comparing the effects of positive bias temperature instability (PBTI) and hot carrier injection (HCI) stresses. In case of hot carrier injection (HCI) stress, the interface trap generation near a p/n+ region was the primary degradation mechanism. However, strong recovery after a high-pressure hydrogen annealing and weak degradation at low temperature indicates that the degradation mechanism of TFET under the HCI stress is different from the high-energy carrier stress induced permanent defect generation mechanism observed in MOSFETs. Further study is necessary to identify the exact location and defect species causing TFET degradation; however, a significant difference is evident between the dominant reliability mechanism of TFET and MOSFET.

Data Envelopment Analysis in the Presence of Measurement Error: Case Study from the National Database of Nursing Quality Indicators® (NDNQI®)

PubMed Central

Gajewski, Byron J.; Lee, Robert; Dunton, Nancy

2012-01-01

Data Envelopment Analysis (DEA) is the most commonly used approach for evaluating healthcare efficiency (Hollingsworth, 2008), but a long-standing concern is that DEA assumes that data are measured without error. This is quite unlikely, and DEA and other efficiency analysis techniques may yield biased efficiency estimates if it is not realized (Gajewski, Lee, Bott, Piamjariyakul and Taunton, 2009; Ruggiero, 2004). We propose to address measurement error systematically using a Bayesian method (Bayesian DEA). We will apply Bayesian DEA to data from the National Database of Nursing Quality Indicators® (NDNQI®) to estimate nursing units’ efficiency. Several external reliability studies inform the posterior distribution of the measurement error on the DEA variables. We will discuss the case of generalizing the approach to situations where an external reliability study is not feasible. PMID:23328796

Ultrasonographic assessment of tendon thickness, Doppler activity and bony spurs of the elbow in patients with lateral epicondylitis and healthy subjects: a reliability and agreement study.

PubMed

Krogh, T P; Fredberg, U; Christensen, R; Stengaard-Pedersen, K; Ellingsen, T

2013-10-01

Tennis elbow, also known as lateral epicondylitis (LE), is a common disorder often assessed by ultrasound. The aim of this study was to evaluate the ultrasonographic outcomes and methods used in LE research and clinical practice. This study was designed as an intra- and interobserver reliability and agreement study. Ultrasonographic examination of the common extensor tendon of the elbow was performed. The intraobserver study examined tendon thickness twice in 20 right elbows from 20 healthy individuals at an interval of 7 to 12 days. The interobserver study examined tendon thickness, color Doppler activity, and bony spurs in 18 right elbows in 9 healthy individuals and 9 patients with LE. Two trained rheumatologists performed the interobserver examinations with the same scanner on the same day. The main outcomes were intra- and interclass correlation (ICC) and agreement. In the intraobserver study, the ICC with regard to tendon thickness ranged from 0.76 to 0.81, depending on the measurement techniques used. The agreement ranged from 0.06 to 0.13 mm. In the interobserver study, the tendon thickness ICC ranged from 0.45 to 0.65 and the agreement ranged from -0.17 to 0.13 mm. The ICC for color Doppler activity was 0.93, with agreement in 14/18 (78 %) of the cases. A perfect reliability was demonstrated for bony spurs, with an ICC of 1 and exact agreement in 18/18 (100 %) of the cases. Good to excellent reliability was obtained for all measurements. The ultrasonographic techniques evaluated in this trial can be recommended for use in both research and clinical practice. © Georg Thieme Verlag KG Stuttgart · New York.

Big data analytics for the Future Circular Collider reliability and availability studies

NASA Astrophysics Data System (ADS)

Begy, Volodimir; Apollonio, Andrea; Gutleber, Johannes; Martin-Marquez, Manuel; Niemi, Arto; Penttinen, Jussi-Pekka; Rogova, Elena; Romero-Marin, Antonio; Sollander, Peter

2017-10-01

Responding to the European Strategy for Particle Physics update 2013, the Future Circular Collider study explores scenarios of circular frontier colliders for the post-LHC era. One branch of the study assesses industrial approaches to model and simulate the reliability and availability of the entire particle collider complex based on the continuous monitoring of CERN’s accelerator complex operation. The modelling is based on an in-depth study of the CERN injector chain and LHC, and is carried out as a cooperative effort with the HL-LHC project. The work so far has revealed that a major challenge is obtaining accelerator monitoring and operational data with sufficient quality, to automate the data quality annotation and calculation of reliability distribution functions for systems, subsystems and components where needed. A flexible data management and analytics environment that permits integrating the heterogeneous data sources, the domain-specific data quality management algorithms and the reliability modelling and simulation suite is a key enabler to complete this accelerator operation study. This paper describes the Big Data infrastructure and analytics ecosystem that has been put in operation at CERN, serving as the foundation on which reliability and availability analysis and simulations can be built. This contribution focuses on data infrastructure and data management aspects and presents case studies chosen for its validation.

Rating the methodological quality of single-subject designs and n-of-1 trials: introducing the Single-Case Experimental Design (SCED) Scale.

PubMed

Tate, Robyn L; McDonald, Skye; Perdices, Michael; Togher, Leanne; Schultz, Regina; Savage, Sharon

2008-08-01

Rating scales that assess methodological quality of clinical trials provide a means to critically appraise the literature. Scales are currently available to rate randomised and non-randomised controlled trials, but there are none that assess single-subject designs. The Single-Case Experimental Design (SCED) Scale was developed for this purpose and evaluated for reliability. Six clinical researchers who were trained and experienced in rating methodological quality of clinical trials developed the scale and participated in reliability studies. The SCED Scale is an 11-item rating scale for single-subject designs, of which 10 items are used to assess methodological quality and use of statistical analysis. The scale was developed and refined over a 3-year period. Content validity was addressed by identifying items to reduce the main sources of bias in single-case methodology as stipulated by authorities in the field, which were empirically tested against 85 published reports. Inter-rater reliability was assessed using a random sample of 20/312 single-subject reports archived in the Psychological Database of Brain Impairment Treatment Efficacy (PsycBITE). Inter-rater reliability for the total score was excellent, both for individual raters (overall ICC = 0.84; 95% confidence interval 0.73-0.92) and for consensus ratings between pairs of raters (overall ICC = 0.88; 95% confidence interval 0.78-0.95). Item reliability was fair to excellent for consensus ratings between pairs of raters (range k = 0.48 to 1.00). The results were replicated with two independent novice raters who were trained in the use of the scale (ICC = 0.88, 95% confidence interval 0.73-0.95). The SCED Scale thus provides a brief and valid evaluation of methodological quality of single-subject designs, with the total score demonstrating excellent inter-rater reliability using both individual and consensus ratings. Items from the scale can also be used as a checklist in the design, reporting and critical appraisal of single-subject designs, thereby assisting to improve standards of single-case methodology.

The validity and reliability of diagnoses of work-related mental ill-health.

PubMed

O'Neill, E; McNamee, R; Agius, R; Gittins, M; Hussey, L; Turner, S

2008-11-01

To establish the reliability and validity of work-related mental ill-health diagnoses. A UK-based surveillance scheme for work-related ill-health involving occupational physicians (OPs) reporting suggests that mental ill-health incidence is increasing by around 13% per year, with anxiety, depression and "other work-related stress" being the most common diagnoses. There have been no studies of the validity and reliability of such diagnoses. Given the existence of a large network of psychiatrists (PSYs) also involved in surveillance of work-related ill-health, an opportunity arose to measure the concurrent validity and reliability of work-related mental ill-health diagnoses. 100 anonymised summaries of cases previously reported by OPs or PSYs were collected; each was sent to 5 PSYs and 5 OPs, who assigned a diagnosis and judged whether the case was work-related. Concurrent validity of the ill-health aspect of the diagnoses, and of the opinion as to work-relatedness, was assessed by comparing the overall classifications of cases by OPs and PSYs. Reliability of the diagnostic classification was measured by kappa matrices. Diagnostic proportions for PSYs and OPs demonstrated good agreement for anxiety, depression, anxiety plus depression and "stress" (11%, 34%, 27%, 14%) and (14%, 30%, 27%, 17%), respectively. In both groups, kappa coefficients were high for a psychotic diagnosis (0.78, 95% CI: 0.74 to 0.83), but not as high for anxiety (0.27, 95% CI: 0.23 to 0.32), depression (0.34, 95% CI: 0.29 to 0.38) and "stress" (0.15, 95% CI: 0.10 to 0.19). The odds ratio of classifying a case as work-related among PSYs compared to OPs was 2.39 (95% CI: 1.68 to 3.38), p<0.001. The overall agreement between OPs and PSYs on mental ill-health diagnoses suggests that OP diagnoses are valid for epidemiological purposes. However, the within-group reliability of the diagnosis "stress" is low. Given differences in judgements about work-relatedness, further research is needed to investigate this aspect of a diagnosis.

Validity of Criteria-Based Content Analysis (CBCA) at Trial in Free-Narrative Interviews

ERIC Educational Resources Information Center

Roma, Paolo; San Martini, Pietro; Sabatello, Ugo; Tatarelli, Roberto; Ferracuti, Stefano

2011-01-01

Objective: The reliability of child witness testimony in sexual abuse cases is often controversial, and few tools are available. Criteria-Based Content Analysis (CBCA) is a widely used instrument for evaluating psychological credibility in cases of suspected child sexual abuse. Only few studies have evaluated CBCA scores in children suspected of…

Alpha-fetoprotein and its value for predicting pregnancy outcomes – a re-evaluation

PubMed Central

Darouich, Ayham Alhaj; Liehr, Thomas; Weise, Anja; Schlembach, Dietmar; Schleußner, Ekkehart; Kiehntopf, Michael; Schreyer, Isolde

2015-01-01

Introduction Alpha-fetoprotein (AFP) concentrations can be determined framing others from invasively acquired amnion fluid (AF-AFP). While the biological role of AFP remains unclear it is well known that AFP-levels can be altered in connection with specific clinical and/or genetic alterations of the fetus. Materials and Method here a retrospective study based on 3,119 singleton and 56 twin pregnancies is presented. The standard levels of amnion fluid derived alpha-fetoprotein level (AF-AFP) between 12th and 36th weeks of gestation were determined. Additionally, acetylcholinesterase (AChE) test results for 63 cases, ultrasonography results for 32 cases and abnormal karyotypic findings for 100 cases were available for selected cases. Results and Discussion according to the present data the AF-AFP test is reliable and provides expected test results in terms of population studies. However, individual AF-AFP test results can be subject to high individual variations. In this study AF-AFP multiple of medians (MoM) over 1.7 were indicative for neuronal tube defects and/or omphalocele in only 6.3% of the cases, while such AF-AFP values were hints on severe sonographic signs in 62% of the cases. Also, altered AF-AFP concentrations were present in 82% of cytogenetically abnormal cases. Overall, even though predicative value of the AF-AFP-test is matter of discussion it continues to be widely applied in invasive prenatal diagnostics. This study indicates that it only can be applied reliably in combination with other tests like banding cytogenetics, ultrasonography and all embedded in well-established genetic counseling. PMID:27358693

An improved spanning tree approach for the reliability analysis of supply chain collaborative network

NASA Astrophysics Data System (ADS)

Lam, C. Y.; Ip, W. H.

2012-11-01

A higher degree of reliability in the collaborative network can increase the competitiveness and performance of an entire supply chain. As supply chain networks grow more complex, the consequences of unreliable behaviour become increasingly severe in terms of cost, effort and time. Moreover, it is computationally difficult to calculate the network reliability of a Non-deterministic Polynomial-time hard (NP-hard) all-terminal network using state enumeration, as this may require a huge number of iterations for topology optimisation. Therefore, this paper proposes an alternative approach of an improved spanning tree for reliability analysis to help effectively evaluate and analyse the reliability of collaborative networks in supply chains and reduce the comparative computational complexity of algorithms. Set theory is employed to evaluate and model the all-terminal reliability of the improved spanning tree algorithm and present a case study of a supply chain used in lamp production to illustrate the application of the proposed approach.

Development and assessment of a digital X-ray software tool to determine vertebral rotation in adolescent idiopathic scoliosis.

PubMed

Eijgenraam, Susanne M; Boselie, Toon F M; Sieben, Judith M; Bastiaenen, Caroline H G; Willems, Paul C; Arts, Jacobus J; Lataster, Arno

2017-02-01

The amount of vertebral rotation in the axial plane is of key importance in the prognosis and treatment of adolescent idiopathic scoliosis (AIS). Current methods to determine vertebral rotation are either designed for use in analogue plain radiographs and not useful in digital images, or lack measurement precision and are therefore less suitable for the follow-up of rotation in AIS patients. This study aimed to develop a digital X-ray software tool with high measurement precision to determine vertebral rotation in AIS, and to assess its (concurrent) validity and reliability. In this study a combination of basic science and reliability methodology applied in both laboratory and clinical settings was used. Software was developed using the algorithm of the Perdriolle torsion meter for analogue AP plain radiographs of the spine. Software was then assessed for (1) concurrent validity and (2) intra- and interobserver reliability. Plain radiographs of both human cadaver vertebrae and outpatient AIS patients were used. Concurrent validity was measured by two independent observers, both experienced in the assessment of plain radiographs. Reliability-measurements were performed by three independent spine surgeons. Pearson correlation of the software compared with the analogue Perdriolle torsion meter for mid-thoracic vertebrae was 0.98, for low-thoracic vertebrae 0.97 and for lumbar vertebrae 0.97. Measurement exactness of the software was within 5° in 62% of cases and within 10° in 97% of cases. Intraclass correlation coefficient (ICC) for inter-observer reliability was 0.92 (0.91-0.95), ICC for intra-observer reliability was 0.96 (0.94-0.97). We developed a digital X-ray software tool to determine vertebral rotation in AIS with a substantial concurrent validity and reliability, which may be useful for the follow-up of vertebral rotation in AIS patients. Copyright © 2015 Elsevier Inc. All rights reserved.

Verification and Validation in a Rapid Software Development Process

NASA Technical Reports Server (NTRS)

Callahan, John R.; Easterbrook, Steve M.

1997-01-01

The high cost of software production is driving development organizations to adopt more automated design and analysis methods such as rapid prototyping, computer-aided software engineering (CASE) tools, and high-level code generators. Even developers of safety-critical software system have adopted many of these new methods while striving to achieve high levels Of quality and reliability. While these new methods may enhance productivity and quality in many cases, we examine some of the risks involved in the use of new methods in safety-critical contexts. We examine a case study involving the use of a CASE tool that automatically generates code from high-level system designs. We show that while high-level testing on the system structure is highly desirable, significant risks exist in the automatically generated code and in re-validating releases of the generated code after subsequent design changes. We identify these risks and suggest process improvements that retain the advantages of rapid, automated development methods within the quality and reliability contexts of safety-critical projects.

Case Studies in Continuous Process Improvement

NASA Technical Reports Server (NTRS)

Mehta, A.

1997-01-01

This study focuses on improving the SMT assembly process in a low-volume, high-reliability environment with emphasis on fine pitch and BGA packages. Before a process improvement is carried out, it is important to evaluate where the process stands in terms of process capability.

CrossTalk: The Journal of Defense Software Engineering. Volume 21, Number 2

DTIC Science & Technology

2008-02-01

data systems are select- ed as tools to provide the data. For example, the Air Force decided to initiate a Reliability Pathfinder to study and define...small projects, and someone just sitting will certainly be noticed more readily. Providing tools for communication such as white boards and open space...community may have to pay for both. In the case of DRILS, we saw that it could potentially interface with the Reliability and Maintainability Infor- mation

Fatigue Reliability of Gas Turbine Engine Structures

NASA Technical Reports Server (NTRS)

Cruse, Thomas A.; Mahadevan, Sankaran; Tryon, Robert G.

1997-01-01

The results of an investigation are described for fatigue reliability in engine structures. The description consists of two parts. Part 1 is for method development. Part 2 is a specific case study. In Part 1, the essential concepts and practical approaches to damage tolerance design in the gas turbine industry are summarized. These have evolved over the years in response to flight safety certification requirements. The effect of Non-Destructive Evaluation (NDE) methods on these methods is also reviewed. Assessment methods based on probabilistic fracture mechanics, with regard to both crack initiation and crack growth, are outlined. Limit state modeling techniques from structural reliability theory are shown to be appropriate for application to this problem, for both individual failure mode and system-level assessment. In Part 2, the results of a case study for the high pressure turbine of a turboprop engine are described. The response surface approach is used to construct a fatigue performance function. This performance function is used with the First Order Reliability Method (FORM) to determine the probability of failure and the sensitivity of the fatigue life to the engine parameters for the first stage disk rim of the two stage turbine. A hybrid combination of regression and Monte Carlo simulation is to use incorporate time dependent random variables. System reliability is used to determine the system probability of failure, and the sensitivity of the system fatigue life to the engine parameters of the high pressure turbine. 'ne variation in the primary hot gas and secondary cooling air, the uncertainty of the complex mission loading, and the scatter in the material data are considered.

Classification of instability after reverse shoulder arthroplasty guides surgical management and outcomes.

PubMed

Abdelfattah, Adham; Otto, Randall J; Simon, Peter; Christmas, Kaitlyn N; Tanner, Gregory; LaMartina, Joey; Levy, Jonathan C; Cuff, Derek J; Mighell, Mark A; Frankle, Mark A

2018-04-01

Revision of unstable reverse shoulder arthroplasty (RSA) remains a significant challenge. The purpose of this study was to determine the reliability of a new treatment-guiding classification for instability after RSA, to describe the clinical outcomes of patients stabilized operatively, and to identify those with higher risk of recurrence. All patients undergoing revision for instability after RSA were identified at our institution. Demographic, clinical, radiographic, and intraoperative data were collected. A classification was developed using all identified causes of instability after RSA and allocating them to 1 of 3 defined treatment-guiding categories. Eight surgeons reviewed all data and applied the classification scheme to each case. Interobserver and intraobserver reliability was used to evaluate the classification scheme. Preoperative clinical outcomes were compared with final follow-up in stabilized shoulders. Forty-three revision cases in 34 patients met the inclusion for study. Five patients remained unstable after revision. Persistent instability most commonly occurred in persistent deltoid dysfunction and postoperative acromial fractures but also in 1 case of soft tissue impingement. Twenty-one patients remained stable at minimum 2 years of follow-up and had significant improvement of clinical outcome scores and range of motion. Reliability of the classification scheme showed substantial and almost perfect interobserver and intraobserver agreement among all the participants (κ = 0.699 and κ = 0.851, respectively). Instability after RSA can be successfully treated with revision surgery using the reliable treatment-guiding classification scheme presented herein. However, more understanding is needed for patients with greater risk of recurrent instability after revision surgery. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Reliability, Validity, and Usability of Data Extraction Programs for Single-Case Research Designs.

PubMed

Moeyaert, Mariola; Maggin, Daniel; Verkuilen, Jay

2016-11-01

Single-case experimental designs (SCEDs) have been increasingly used in recent years to inform the development and validation of effective interventions in the behavioral sciences. An important aspect of this work has been the extension of meta-analytic and other statistical innovations to SCED data. Standard practice within SCED methods is to display data graphically, which requires subsequent users to extract the data, either manually or using data extraction programs. Previous research has examined issues of reliability and validity of data extraction programs in the past, but typically at an aggregate level. Little is known, however, about the coding of individual data points. We focused on four different software programs that can be used for this purpose (i.e., Ungraph, DataThief, WebPlotDigitizer, and XYit), and examined the reliability of numeric coding, the validity compared with real data, and overall program usability. This study indicates that the reliability and validity of the retrieved data are independent of the specific software program, but are dependent on the individual single-case study graphs. Differences were found in program usability in terms of user friendliness, data retrieval time, and license costs. Ungraph and WebPlotDigitizer received the highest usability scores. DataThief was perceived as unacceptable and the time needed to retrieve the data was double that of the other three programs. WebPlotDigitizer was the only program free to use. As a consequence, WebPlotDigitizer turned out to be the best option in terms of usability, time to retrieve the data, and costs, although the usability scores of Ungraph were also strong. © The Author(s) 2016.

Electronic synoptic operative reporting: assessing the reliability and completeness of synoptic reports for pancreatic resection.

PubMed

Park, Jason; Pillarisetty, Venu G; Brennan, Murray F; Jarnagin, William R; D'Angelica, Michael I; Dematteo, Ronald P; G Coit, Daniel; Janakos, Maria; Allen, Peter J

2010-09-01

Electronic synoptic operative reports (E-SORs) have replaced dictated reports at many institutions, but whether E-SORs adequately document the components and findings of an operation has received limited study. This study assessed the reliability and completeness of E-SORs for pancreatic surgery developed at our institution. An attending surgeon and surgical fellow prospectively and independently completed an E-SOR after each of 112 major pancreatic resections (78 proximal, 29 distal, and 5 central) over a 10-month period (September 2008 to June 2009). Reliability was assessed by calculating the interobserver agreement between attending physician and fellow reports. Completeness was assessed by comparing E-SORs to a case-matched (surgeon and procedure) historical control of dictated reports, using a 39-item checklist developed through an internal and external query of 13 high-volume pancreatic surgeons. Interobserver agreement between attending and fellow was moderate to very good for individual categorical E-SOR items (kappa = 0.65 to 1.00, p < 0.001 for all items). Compared with dictated reports, E-SORs had significantly higher completeness checklist scores (mean 88.8 +/- 5.4 vs 59.6 +/- 9.2 [maximum possible score, 100], p < 0.01) and were available in patients' electronic records in a significantly shorter interval of time (median 0.5 vs 5.8 days from case end, p < 0.01). The mean time taken to complete E-SORs was 4.0 +/- 1.6 minutes per case. E-SORs for pancreatic surgery are reliable, complete in data collected, and rapidly available, all of which support their clinical implementation. The inherent strengths of E-SORs offer real promise of a new standard for operative reporting and health communication. Copyright 2010 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

An interrater reliability study of the Braden scale in two nursing homes.

PubMed

Kottner, Jan; Dassen, Theo

2008-10-01

Adequate risk assessment is essential in pressure ulcer prevention. Assessment scales were designed to support practitioners in identifying persons at pressure ulcer risk. The Braden scale is one of the most extensively studied risk assessment instruments, although the majority of studies focused on validity rather than reliability. The first aim was to measure the interrater reliability of the Braden scale and its individual items. The second aim was to study different statistical approaches regarding interrater reliability estimation. An interrater reliability study was conducted in two German nursing homes. Residents (n = 152) from 8 units were assessed twice. The raters were trained nurses with a work experience ranging from 0.5 to 30 years. Data were analysed using an overall percentage of agreement, weighted and unweighted kappa and the intraclass correlation coefficient. Differences between nurses rating the overall Braden score ranged from 0 up to 9 points. Interrater reliability expressed by the intraclass correlation coefficient ranged from 0.73 (95% CI 0.26 - 0.91) to 0.95 (95% CI 0.87 - 0.98). Calculated intraclass correlation coefficients for individual items ranged from 0.06 (95% CI -0.31 to 0.48) to 0.97 (95% CI 0.93-0.99) with the lowest values being measured for the items "sensory perception" and "nutrition". There was no association between work experience and the level of interrater reliability. With two exceptions, simple kappa-values were always lower than weighted kappa-values and intraclass correlation coefficients. Although the calculated interrater reliability coefficients for the total Braden score were high in some cases, several clinically relevant differences occurred between the nurses. Due to interrater reliability being very low for the items "sensory perception" and "nutrition", it is doubtful if their assessment contributes to any valid results. The calculation of weighted kappa or intraclass correlation coefficients is the most appropriate interrater reliability estimates.

Deformation of Cases in High Capacitance Value Wet Tantalum Capacitors under Environmental Stresses

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2016-01-01

Internal gas pressure in hermetic wet tantalum capacitors is created by air, electrolyte vapor, and gas generated by electrochemical reactions at the electrodes. This pressure increases substantially with temperature and time of operation due to excessive leakage currents. Deformation of the case occurs when the internal pressure exceeds pressure of the environments and can raise significantly when a part operates in space. Contrary to the cylinder case wet tantalum capacitors that have external sealing by welding and internal sealing provided by the Teflon bushing and crimping of the case, no reliable internal sealing exists in the button case capacitors. Single seal design capacitors are used for high capacitance value wet tantalum capacitors manufactured per DLA L&M drawings #04003, 04005, and 10011, and require additional analysis to assure their reliable application in space systems. In this work, leakage currents and case deformation of button case capacitors were measured during different environmental test conditions. Recommendations for derating, screening and qualification testing are given. This work is a continuation of a series of NEPP reports related to quality and reliability of wet tantalum capacitors.

Reliability Practice at NASA Goddard Space Flight Center

NASA Technical Reports Server (NTRS)

Pruessner, Paula S.; Li, Ming

2008-01-01

This paper describes in brief the Reliability and Maintainability (R&M) Programs performed directly by the reliability branch at Goddard Space Flight Center (GSFC). The mission assurance requirements flow down is explained. GSFC practices for PRA, reliability prediction/fault tree analysis/reliability block diagram, FMEA, part stress and derating analysis, worst case analysis, trend analysis, limit life items are presented. Lessons learned are summarized and recommendations on improvement are identified.

The cleanroom case study in the Software Engineering Laboratory: Project description and early analysis

NASA Technical Reports Server (NTRS)

Green, Scott; Kouchakdjian, Ara; Basili, Victor; Weidow, David

1990-01-01

This case study analyzes the application of the cleanroom software development methodology to the development of production software at the NASA/Goddard Space Flight Center. The cleanroom methodology emphasizes human discipline in program verification to produce reliable software products that are right the first time. Preliminary analysis of the cleanroom case study shows that the method can be applied successfully in the FDD environment and may increase staff productivity and product quality. Compared to typical Software Engineering Laboratory (SEL) activities, there is evidence of lower failure rates, a more complete and consistent set of inline code documentation, a different distribution of phase effort activity, and a different growth profile in terms of lines of code developed. The major goals of the study were to: (1) assess the process used in the SEL cleanroom model with respect to team structure, team activities, and effort distribution; (2) analyze the products of the SEL cleanroom model and determine the impact on measures of interest, including reliability, productivity, overall life-cycle cost, and software quality; and (3) analyze the residual products in the application of the SEL cleanroom model, such as fault distribution, error characteristics, system growth, and computer usage.

The reliability of the pass/fail decision for assessments comprised of multiple components.

PubMed

Möltner, Andreas; Tımbıl, Sevgi; Jünger, Jana

2015-01-01

The decision having the most serious consequences for a student taking an assessment is the one to pass or fail that student. For this reason, the reliability of the pass/fail decision must be determined for high quality assessments, just as the measurement reliability of the point values. Assessments in a particular subject (graded course credit) are often composed of multiple components that must be passed independently of each other. When "conjunctively" combining separate pass/fail decisions, as with other complex decision rules for passing, adequate methods of analysis are necessary for estimating the accuracy and consistency of these classifications. To date, very few papers have addressed this issue; a generally applicable procedure was published by Douglas and Mislevy in 2010. Using the example of an assessment comprised of several parts that must be passed separately, this study analyzes the reliability underlying the decision to pass or fail students and discusses the impact of an improved method for identifying those who do not fulfill the minimum requirements. The accuracy and consistency of the decision to pass or fail an examinee in the subject cluster Internal Medicine/General Medicine/Clinical Chemistry at the University of Heidelberg's Faculty of Medicine was investigated. This cluster requires students to separately pass three components (two written exams and an OSCE), whereby students may reattempt to pass each component twice. Our analysis was carried out using the method described by Douglas and Mislevy. Frequently, when complex logical connections exist between the individual pass/fail decisions in the case of low failure rates, only a very low reliability for the overall decision to grant graded course credit can be achieved, even if high reliabilities exist for the various components. For the example analyzed here, the classification accuracy and consistency when conjunctively combining the three individual parts is relatively low with κ=0.49 or κ=0.47, despite the good reliability of over 0.75 for each of the three components. The option to repeat each component twice leads to a situation in which only about half of the candidates who do not satisfy the minimum requirements would fail the overall assessment, while the other half is able to continue their studies despite having deficient knowledge and skills. The method put forth by Douglas and Mislevy allows the analysis of the decision accuracy and consistency for complex combinations of scores from different components. Even in the case of highly reliable components, it is not necessarily so that a reliable pass/fail decision has been reached - for instance in the case of low failure rates. Assessments must be administered with the explicit goal of identifying examinees that do not fulfill the minimum requirements.

The reliability of the pass/fail decision for assessments comprised of multiple components

PubMed Central

Möltner, Andreas; Tımbıl, Sevgi; Jünger, Jana

2015-01-01

Objective: The decision having the most serious consequences for a student taking an assessment is the one to pass or fail that student. For this reason, the reliability of the pass/fail decision must be determined for high quality assessments, just as the measurement reliability of the point values. Assessments in a particular subject (graded course credit) are often composed of multiple components that must be passed independently of each other. When “conjunctively” combining separate pass/fail decisions, as with other complex decision rules for passing, adequate methods of analysis are necessary for estimating the accuracy and consistency of these classifications. To date, very few papers have addressed this issue; a generally applicable procedure was published by Douglas and Mislevy in 2010. Using the example of an assessment comprised of several parts that must be passed separately, this study analyzes the reliability underlying the decision to pass or fail students and discusses the impact of an improved method for identifying those who do not fulfill the minimum requirements. Method: The accuracy and consistency of the decision to pass or fail an examinee in the subject cluster Internal Medicine/General Medicine/Clinical Chemistry at the University of Heidelberg’s Faculty of Medicine was investigated. This cluster requires students to separately pass three components (two written exams and an OSCE), whereby students may reattempt to pass each component twice. Our analysis was carried out using the method described by Douglas and Mislevy. Results: Frequently, when complex logical connections exist between the individual pass/fail decisions in the case of low failure rates, only a very low reliability for the overall decision to grant graded course credit can be achieved, even if high reliabilities exist for the various components. For the example analyzed here, the classification accuracy and consistency when conjunctively combining the three individual parts is relatively low with κ=0.49 or κ=0.47, despite the good reliability of over 0.75 for each of the three components. The option to repeat each component twice leads to a situation in which only about half of the candidates who do not satisfy the minimum requirements would fail the overall assessment, while the other half is able to continue their studies despite having deficient knowledge and skills. Conclusion: The method put forth by Douglas and Mislevy allows the analysis of the decision accuracy and consistency for complex combinations of scores from different components. Even in the case of highly reliable components, it is not necessarily so that a reliable pass/fail decision has been reached – for instance in the case of low failure rates. Assessments must be administered with the explicit goal of identifying examinees that do not fulfill the minimum requirements. PMID:26483855

Inter-rater reliability of twelve diagnostic systems of schizophrenia.

PubMed

Helmes, E; Landmark, J; Kazarian, S S

1983-05-01

The present and past symptomatology of 31 chronic schizophrenics was rated by four independent judges, two experienced clinical psychiatrists and two psychiatric residents, in a context more representative of actual clinical practice than most research studies. Ratings were made on 64 symptoms derived from 12 diagnostic systems, based on either live or videotaped interviews for present symptomatology and case records for past symptomatology. Inter-rater reliabilities were higher for present than for past symptoms, and in general did not approach those reported for highly trained raters. There were no differences between live and videotaped interviews. Diagnostic systems differed widely in rater agreement. The most consistent across both past and present symptomatology were the systems of Langfeldt, Schneider, and DSM-III, for which the level of reliability was consistent with other studies.

Alcohol, caffeine, and nicotine consumption in adolescents: hair analysis versus self-report.

PubMed

Bertol, Elisabetta; Vaiano, Fabio; Boscolo-Berto, Rafael; Fioravanti, Alessia; Palumbo, Diego; Catalani, Valeria; Mari, Francesco; Patussi, Valentino; Serpelloni, Giovanni

2017-05-01

Clinical reliability of self-reported data for alcohol, caffeine, and nicotine consumptions is lacking, particularly in adolescents. To compare a self-report questionnaire and hair analysis to assess the reliability and effectiveness of the self-report. A cross-sectional study on 14-15-year-old Italian students (n = 874, 38% males, 62% females) was performed comparing self-reported data to hair analysis. The latter quantified hair concentrations of caffeine, nicotine, cotinine, ethyl glucuronide (EtG), and fatty acid ethyl esters (FAEEs) using mass spectrometry. Concordance between self-report and hair testing ranged from good to poor across substances and levels of use: poor for heavy alcohol intake (EtG: k = 0.36, 20 positive cases by hair analysis, false negative by self-report, 2.3% of total sample; FAEE k = 0.31, 25 positive cases, 2.9% of total sample); fair to poor for active smokers (k = 0.40, 125 positive cases, 14.3% of total sample); and moderate for caffeine (k = 0.57, 56 positive cases, 6.4% of total sample). Epidemiological studies on alcohol, caffeine, and nicotine consumption in adolescents may benefit from the inclusion of toxicological analysis on hair samples to overcome the under-reporting phenomenon of questionnaires and detect more cases of problematic substance use.

Measurement of inter- and intra-annual variability of landscape fire activity at a continental scale: The Australian case

Treesearch

Grant J. Williamson; Lynda D. Prior; Matt Jolly; Mark A. Cochrane; Brett P. Murphy; David M. J. S. Bowman

2016-01-01

Climate dynamics at diurnal, seasonal and inter-annual scales shape global fire activity, although difficulties of assembling reliable fire and meteorological data with sufficient spatio-temporal resolution have frustrated quantification of this variability. Using Australia as a case study, we combine data from 4760 meteorological stations with 12 years of satellite-...

A histomorphological study of sarcoptic acariasis in the dog: 19 cases.

PubMed

Morris, D O; Dunstan, R W

1996-01-01

Nineteen cases of canine sarcoptic acariasis (Sarcoptes scabiei var. canis) were diagnosed histologically by identifying sarcoptic mites present in the stratum corneum. The inflammatory responses to these mites could be staged as early, fully developed, or late lesions. No histomorphological features were identified that could serve as reliable markers of infestation in the absence of a sectioned mite.

Numerical simulations of atmospheric dispersion of iodine-131 by different models.

PubMed

Leelőssy, Ádám; Mészáros, Róbert; Kovács, Attila; Lagzi, István; Kovács, Tibor

2017-01-01

Nowadays, several dispersion models are available to simulate the transport processes of air pollutants and toxic substances including radionuclides in the atmosphere. Reliability of atmospheric transport models has been demonstrated in several recent cases from local to global scale; however, very few actual emission data are available to evaluate model results in real-life cases. In this study, the atmospheric dispersion of 131I emitted to the atmosphere during an industrial process was simulated with different models, namely the WRF-Chem Eulerian online coupled model and the HYSPLIT and the RAPTOR Lagrangian models. Although only limited data of 131I detections has been available, the accuracy of modeled plume direction could be evaluated in complex late autumn weather situations. For the studied cases, the general reliability of models has been demonstrated. However, serious uncertainties arise related to low level inversions, above all in case of an emission event on 4 November 2011, when an important wind shear caused a significant difference between simulated and real transport directions. Results underline the importance of prudent interpretation of dispersion model results and the identification of weather conditions with a potential to cause large model errors.

Numerical simulations of atmospheric dispersion of iodine-131 by different models

PubMed Central

Leelőssy, Ádám; Mészáros, Róbert; Kovács, Attila; Lagzi, István; Kovács, Tibor

2017-01-01

Nowadays, several dispersion models are available to simulate the transport processes of air pollutants and toxic substances including radionuclides in the atmosphere. Reliability of atmospheric transport models has been demonstrated in several recent cases from local to global scale; however, very few actual emission data are available to evaluate model results in real-life cases. In this study, the atmospheric dispersion of 131I emitted to the atmosphere during an industrial process was simulated with different models, namely the WRF-Chem Eulerian online coupled model and the HYSPLIT and the RAPTOR Lagrangian models. Although only limited data of 131I detections has been available, the accuracy of modeled plume direction could be evaluated in complex late autumn weather situations. For the studied cases, the general reliability of models has been demonstrated. However, serious uncertainties arise related to low level inversions, above all in case of an emission event on 4 November 2011, when an important wind shear caused a significant difference between simulated and real transport directions. Results underline the importance of prudent interpretation of dispersion model results and the identification of weather conditions with a potential to cause large model errors. PMID:28207853

Validation of the Italian Version of the Caregiver Abuse Screen among Family Caregivers of Older People with Alzheimer's Disease.

PubMed

Melchiorre, Maria Gabriella; Di Rosa, Mirko; Barbabella, Francesco; Barbini, Norma; Lattanzio, Fabrizia; Chiatti, Carlos

2017-01-01

Introduction . Elder abuse is often a hidden phenomenon and, in many cases, screening practices are difficult to implement among older people with dementia. The Caregiver Abuse Screen (CASE) is a useful tool which is administered to family caregivers for detecting their potential abusive behavior. Objectives . To validate the Italian version of the CASE tool in the context of family caregiving of older people with Alzheimer's disease (AD) and to identify risk factors for elder abuse in Italy. Methods . The CASE test was administered to 438 caregivers, recruited in the Up-Tech study. Validity and reliability were evaluated using Spearman's correlation coefficients, principal-component analysis, and Cronbach's alphas. The association between the CASE and other variables potentially associated with elder abuse was also analyzed. Results . The factor analysis suggested the presence of a single factor, with a strong internal consistency (Cronbach's alpha = 0.86). CASE score was strongly correlated with well-known risk factors of abuse. At multivariate level, main factors associated with CASE total score were caregiver burden and AD-related behavioral disturbances. Conclusions . The Italian version of the CASE is a reliable and consistent screening tool for tackling the risk of being or becoming perpetrators of abuse by family caregivers of people with AD.

Validation of the Italian Version of the Caregiver Abuse Screen among Family Caregivers of Older People with Alzheimer's Disease

PubMed Central

Di Rosa, Mirko; Barbabella, Francesco; Barbini, Norma; Chiatti, Carlos

2017-01-01

Introduction. Elder abuse is often a hidden phenomenon and, in many cases, screening practices are difficult to implement among older people with dementia. The Caregiver Abuse Screen (CASE) is a useful tool which is administered to family caregivers for detecting their potential abusive behavior. Objectives. To validate the Italian version of the CASE tool in the context of family caregiving of older people with Alzheimer's disease (AD) and to identify risk factors for elder abuse in Italy. Methods. The CASE test was administered to 438 caregivers, recruited in the Up-Tech study. Validity and reliability were evaluated using Spearman's correlation coefficients, principal-component analysis, and Cronbach's alphas. The association between the CASE and other variables potentially associated with elder abuse was also analyzed. Results. The factor analysis suggested the presence of a single factor, with a strong internal consistency (Cronbach's alpha = 0.86). CASE score was strongly correlated with well-known risk factors of abuse. At multivariate level, main factors associated with CASE total score were caregiver burden and AD-related behavioral disturbances. Conclusions. The Italian version of the CASE is a reliable and consistent screening tool for tackling the risk of being or becoming perpetrators of abuse by family caregivers of people with AD. PMID:28265571

Human Reliability Analysis in Support of Risk Assessment for Positive Train Control

DOT National Transportation Integrated Search

2003-06-01

This report describes an approach to evaluating the reliability of human actions that are modeled in a probabilistic risk assessment : (PRA) of train control operations. This approach to human reliability analysis (HRA) has been applied in the case o...

Assessing the surgical skills of trainees in the operating theatre: a prospective observational study of the methodology.

PubMed

Beard, J D; Marriott, J; Purdie, H; Crossley, J

2011-01-01

To compare user satisfaction and acceptability, reliability and validity of three different methods of assessing the surgical skills of trainees by direct observation in the operating theatre across a range of different surgical specialties and index procedures. A 2-year prospective, observational study in the operating theatres of three teaching hospitals in Sheffield. The assessment methods were procedure-based assessment (PBA), Objective Structured Assessment of Technical Skills (OSATS) and Non-technical Skills for Surgeons (NOTSS). The specialties were obstetrics and gynaecology (O&G) and upper gastrointestinal, colorectal, cardiac, vascular and orthopaedic surgery. Two to four typical index procedures were selected from each specialty. Surgical trainees were directly observed performing typical index procedures and assessed using a combination of two of the three methods (OSATS or PBA and NOTSS for O&G, PBA and NOTSS for the other specialties) by the consultant clinical supervisor for the case and the anaesthetist and/or scrub nurse, as well as one or more independent assessors from the research team. Information on user satisfaction and acceptability of each assessment method from both assessor and trainee perspectives was obtained from structured questionnaires. The reliability of each method was measured using generalisability theory. Aspects of validity included the internal structure of each tool and correlation between tools, construct validity, predictive validity, interprocedural differences, the effect of assessor designation and the effect of assessment on performance. Of the 558 patients who were consented, a total of 437 (78%) cases were included in the study: 51 consultant clinical supervisors, 56 anaesthetists, 39 nurses, 2 surgical care practitioners and 4 independent assessors provided 1635 assessments on 85 trainees undertaking the 437 cases. A total of 749 PBAs, 695 NOTSS and 191 OSATSs were performed. Non-O&G clinical supervisors and trainees provided mixed, but predominantly positive, responses about a range of applications of PBA. Most felt that PBA was important in surgical education, and would use it again in the future and did not feel that it added time to the operating list. The overall satisfaction of O&G clinical supervisors and trainees with OSATS was not as high, and a majority of those who used both preferred PBA. A majority of anaesthetists and nurses felt that NOTSS allowed them to rate interpersonal skills (communication, teamwork and leadership) more easily than cognitive skills (situation awareness and decision-making), that it had formative value and that it was a valuable adjunct to the assessment of technical skills. PBA demonstrated high reliability (G > 0.8 for only three assessor judgements on the same index procedure). OSATS had lower reliability (G > 0.8 for five assessor judgements on the same index procedure). Both were less reliable on a mix of procedures because of strong procedure-specific factors. A direct comparison of PBA between O&G and non-O&G cases showed a striking difference in reliability. Within O&G, a good level of reliability (G > 0.8) could not be obtained using a feasible number of assessments. Conversely, the reliability within non-O&G cases was exceptionally high, with only two assessor judgements being required. The reasons for this difference probably include the more summative purpose of assessment in O&G and the much higher proportion of O&G trainees in this study with training concerns (42% vs 4%). The reliability of NOTSS was lower than that for PBA. Reliability for the same procedure (G > 0.8) required six assessor judgements. However, as procedure-specific factors exerted a lesser influence on NOTSS, reliability on a mix of procedures could be achieved using only eight assessor judgements. NOTSS also demonstrated a valid internal structure. The strongest correlations between NOTSS and PBA or OSATS were in the 'decision-making' domain. PBA and NOTSS showed better construct validity than OSATS, the year of training and the number of recent index procedures performed being significant independent predictors of performance. There was little variation in scoring between different procedures or different designations of assessor. The results suggest that PBA is a reliable and acceptable method of assessing surgical skills, with good construct validity. Specialties that use OSATS may wish to consider changing the design or switching to PBA. Whatever workplace-based assessment method is used, the purpose, timing and frequency of assessment require detailed guidance. NOTSS is a promising tool for the assessment of non-technical skills, and surgical specialties may wish to consider its inclusion in their assessment framework. Further research is required into the use of health-care professionals other than consultant surgeons to assess trainees, the relationship between performance and experience, the educational impact of assessment and the additional value of video recording.

[Mathematic analysis of risk factors influence on occupational respiratory diseases development].

PubMed

Budkar', L N; Bugaeva, I V; Obukhova, T Iu; Tereshina, L G; Karpova, E A; Shmonina, O G

2010-01-01

Analysis covered 1348 case histories of workers exposed to industrial dust in Urals region. The analysis applied mathematical processing of survival theory and correlation analysis. The authors studied influence of various factors: dust concentration, connective tissue dysplasia, smoking habits--on duration for diseases caused by dust to appear. Findings are that occupational diseases develop reliably faster with higher ambient dust concentrations and with connective tissue dysplasia syndrome. Smoking habits do not alter duration of pneumoconiosis development, but reliably increases development of occupational dust bronchitis.

How informative are case studies of spider bites in the medical literature?

PubMed

Stuber, Marielle; Nentwig, Wolfgang

2016-05-01

We analyzed the reliability and information content of 134 medical case studies on spider bites, published in 91 journal articles. Overall, we found that only 22% of these studies fulfilled the criteria for a verified spider bite. This means that the majority of such case studies cannot be attributed to a given spider species and usually not even to a spider. Their scientific value is negligible, moreover, such publications are even dangerous because they suggest incorrect conclusions. Secondly, we found that such case studies usually do not follow an obvious structure and many details on the development of symptoms, therapy and healing process are widely lacking. So even for verified spider bites, the comparability of case studies is limited. We discuss the obvious failure of a reviewing process for case studies and give recommendations how to increase the currently low information content of medical case studies on spider bites. Copyright © 2016 Elsevier Ltd. All rights reserved.

M-OSCE as a method to measure dental hygiene students' critical thinking: a pilot study.

PubMed

McComas, Martha J; Wright, Rebecca A; Mann, Nancy K; Cooper, Mary D; Jacks, Mary E

2013-04-01

Educators in all academic disciplines have been encouraged to utilize assessment strategies to evaluate students' critical thinking. The purpose of this study was to assess the viability of the modified objective structured clinical examination (m-OSCE) to evaluate critical thinking in dental hygiene education. This evaluation utilized a convenience sample of senior dental hygiene students. Students participated in the m-OSCE in which portions of a patient case were revealed at four stations. The exam consisted of multiple-choice questions intended to measure students' ability to utilize critical thinking skills. Additionally, there was one fill-in-the-blank question and a treatment plan that was completed at the fifth station. The results of this study revealed that the m-OSCE did not reliably measure dental hygiene students' critical thinking. Statistical analysis found no satisfactory reliability within the multiple-choice questions and moderately reliable results within the treatment planning portion of the examination. In addition, the item analysis found gaps in students' abilities to transfer clinical evidence/data to basic biomedical knowledge as demonstrated through the multiple-choice questioning results. This outcome warrants further investigation of the utility of the m-OSCE, with a focus on modifications to the evaluation questions, grading rubric, and patient case.

Improved reliability in skeletal age assessment using a pediatric hand MR scanner with a 0.3T permanent magnet.

PubMed

Terada, Yasuhiko; Kono, Saki; Uchiumi, Tomomi; Kose, Katsumi; Miyagi, Ryo; Yamabe, Eiko; Fujinaga, Yasunari; Yoshioka, Hiroshi

2014-01-01

The purpose of this study was to improve the reliability and validity of skeletal age assessment using an open and compact pediatric hand magnetic resonance (MR) imaging scanner. We used such a scanner with 0.3-tesla permanent magnet to image the left hands of 88 healthy children (aged 3.4 to 15.7 years, mean 8.8 years), and 3 raters (2 orthopedic specialists and a radiologist) assessed skeletal age using those images. We measured the strength of agreement in ratings by values of weighted Cohen's κ and the proportion of cases excluded from rating because of motion artifact and inappropriate positioning. We compared the current results with those of a previous study in which 93 healthy children (aged 4.1 to 16.4 years, mean 9.7 years) were examined with an adult hand scanner. The κ values between raters exceeded 0.80, which indicates almost perfect agreement, and most were higher than those of the previous study. The proportion of cases excluded from rating because of motion artifact or inappropriate positioning was also reduced. The results indicate that use of the compact pediatric hand scanner improved the reliability and validity of skeletal age assessments.

Management of reliability and maintainability; a disciplined approach to fleet readiness

NASA Technical Reports Server (NTRS)

Willoughby, W. J., Jr.

1981-01-01

Material acquisition fundamentals were reviewed and include: mission profile definition, stress analysis, derating criteria, circuit reliability, failure modes, and worst case analysis. Military system reliability was examined with emphasis on the sparing of equipment. The Navy's organizational strategy for 1980 is presented.

Research on Novel Algorithms for Smart Grid Reliability Assessment and Economic Dispatch

NASA Astrophysics Data System (ADS)

Luo, Wenjin

In this dissertation, several studies of electric power system reliability and economy assessment methods are presented. To be more precise, several algorithms in evaluating power system reliability and economy are studied. Furthermore, two novel algorithms are applied to this field and their simulation results are compared with conventional results. As the electrical power system develops towards extra high voltage, remote distance, large capacity and regional networking, the application of a number of new technique equipments and the electric market system have be gradually established, and the results caused by power cut has become more and more serious. The electrical power system needs the highest possible reliability due to its complication and security. In this dissertation the Boolean logic Driven Markov Process (BDMP) method is studied and applied to evaluate power system reliability. This approach has several benefits. It allows complex dynamic models to be defined, while maintaining its easy readability as conventional methods. This method has been applied to evaluate IEEE reliability test system. The simulation results obtained are close to IEEE experimental data which means that it could be used for future study of the system reliability. Besides reliability, modern power system is expected to be more economic. This dissertation presents a novel evolutionary algorithm named as quantum evolutionary membrane algorithm (QEPS), which combines the concept and theory of quantum-inspired evolutionary algorithm and membrane computation, to solve the economic dispatch problem in renewable power system with on land and offshore wind farms. The case derived from real data is used for simulation tests. Another conventional evolutionary algorithm is also used to solve the same problem for comparison. The experimental results show that the proposed method is quick and accurate to obtain the optimal solution which is the minimum cost for electricity supplied by wind farm system.

Characterizing Treatable Causes of Small-Fiber Polyneuropathy in Gulf War Veterans

DTIC Science & Technology

2017-10-01

this study Global experts participated in additional rounds of a Delphi process to determine the most reliable markers for SFPN ( Case Definition). We...We supplemented the pertinent information on SFPN and added a link to this study as a recruitment tool. The public portion of the website may be...propose as part of the Case Definition. The database currently contains data on 3,495 subjects consisting of 3,087 patients and 408 healthy controls

Reliable harvest of a dorsal scapular artery perforator flap by augmenting its perfusion.

PubMed

Kim, So-Young; Lee, Kyeong-Tae; Mun, Goo-Hyun

2016-02-01

Despite confirmation of a reliable perforasome in the dorsal scapular artery in an anatomic study, a true perforator flap has not been recommended in previous clinical studies because of concerns regarding insufficient perfusion in the distal region. In this report, we present two cases of reconstruction for occipital defects caused by tumor extirpation using pedicled dorsal scapular artery perforator flaps without a muscle component. To secure the perfusion of the dorsal scapular artery perforator flap, inclusion of an additional perforator was attempted for perfusion augmentation. The second dorsal scapular artery perforator was harvested in one case. In an additional case, the sixth dorsal intercostal artery perforator with a branch that directly connected with the dorsal scapular artery within the trapezius muscle was additionally harvested. The flaps survived without any perfusion-related complications, including tip necrosis, and no donor site morbidities were observed. We suggest that a perfusion augmented dorsal scapular artery perforator flap by harvesting multiple perforators could be a safe and useful alternative for reconstructive surgery of head and neck defects. © 2014 Wiley Periodicals, Inc.

Reporting of occupational injury and illness in the semiconductor manufacturing industry.

PubMed

McCurdy, S A; Schenker, M B; Samuels, S J

1991-01-01

In the United States, occupational illness and injury cases meeting specific reporting criteria are recorded on company Occupational Safety and Health Administration (OSHA) 200 logs; case description data are submitted to participating state agencies for coding and entry in the national Supplementary Data System (SDS). We evaluated completeness of reporting (the percentage of reportable cases that were recorded in the company OSHA 200 log) in the semiconductor manufacturing industry by reviewing company health clinic records for 1984 of 10 manufacturing sites of member companies of a national semiconductor manufacturing industry trade association. Of 416 randomly selected work-related cases, 101 met OSHA reporting criteria. Reporting completeness was 60 percent and was lowest for occupational illnesses (44 percent). Case-description data from 150 reported cases were submitted twice to state coding personnel to evaluate coding reliability. Reliability was high (kappa 0.82-0.93) for "nature," "affected body part," "source," and "type" variables. Coding for the SDS appears reliable; reporting completeness may be improved by use of a stepwise approach by company personnel responsible for reporting decisions.

Postmortem time estimation using body temperature and a finite-element computer model.

PubMed

den Hartog, Emiel A; Lotens, Wouter A

2004-09-01

In the Netherlands most murder victims are found 2-24 h after the crime. During this period, body temperature decrease is the most reliable method to estimate the postmortem time (PMT). Recently, two murder cases were analysed in which currently available methods did not provide a sufficiently reliable estimate of the PMT. In both cases a study was performed to verify the statements of suspects. For this purpose a finite-element computer model was developed that simulates a human torso and its clothing. With this model, changes to the body and the environment can also be modelled; this was very relevant in one of the cases, as the body had been in the presence of a small fire. In both cases it was possible to falsify the statements of the suspects by improving the accuracy of the PMT estimate. The estimated PMT in both cases was within the range of Henssge's model. The standard deviation of the PMT estimate was 35 min in the first case and 45 min in the second case, compared to 168 min (2.8 h) in Henssge's model. In conclusion, the model as presented here can have additional value for improving the accuracy of the PMT estimate. In contrast to the simple model of Henssge, the current model allows for increased accuracy when more detailed information is available. Moreover, the sensitivity of the predicted PMT for uncertainty in the circumstances can be studied, which is crucial to the confidence of the judge in the results.

Reliability of a Malay-translated questionnaire for use in a hand-arm vibration syndrome study in Malaysia.

PubMed

Su, T A; Hoe, V C W

2008-12-01

Validity and reliability of the information relating to hand-transmitted vibration exposure and vibration-related health outcome are very important for case finding in hand-arm vibration syndrome (HAVS) studies. In a local HAVS study among a group of construction workers in Kuala Lumpur, Malaysia, a questionnaire translated into Malay was created based on the Hand-transmitted Vibration Health Surveillance--Initial Questionnaire and Clinical Assessment, from Vibration Injury Network. This study was conducted to determine the reliability of standardised questions in the questionnaire used in the study. 15 subjects were selected randomly from the sampling frame of the HAVS study. Test-retest reliability was conducted on all items contained in parts 1-6 of the questionnaire and clinical assessment form, with an interval of 13-14 days between the first and second administration. Kappa coefficient and percentage agreement were calculated for all standardised questions. The kappa coefficient and percentage agreement for all standardised questions varied from -0.174 to 1.000 and 66.7 to 100.0 percent, respectively. The kappa coefficient for important questions related to current vibratory tool usage, tingling, numbness and hand grip weakness were 0.714, 0.432, -0.077 and -0.120, respectively, while the percentage agreement for current vibratory tool usage, finger colour change, tingling, numbness and hand grip weakness were 85.7 percent, 92.8 percent, 79.5 percent, 85.7 percent and 71.4 percent, respectively. Intra-rater reliability on the extent of vibration exposure was good, with the intra-class correlation coefficient (95 percent confidence interval) ranging from 0.786 (0.334-0.931) to 0.975 (0.923-0.992). Critical questions on vascular, neurological and musculoskeletal symptoms of HAVS were found to be reliable. The history on the extent of vibration exposure revealed good reliability when explored by the investigator alone. This questionnaire is considered reliable to be used in the study of HAVS among construction workers working in a construction site.

Bridge reliability assessment based on the PDF of long-term monitored extreme strains

NASA Astrophysics Data System (ADS)

Jiao, Meiju; Sun, Limin

2011-04-01

Structural health monitoring (SHM) systems can provide valuable information for the evaluation of bridge performance. As the development and implementation of SHM technology in recent years, the data mining and use has received increasingly attention and interests in civil engineering. Based on the principle of probabilistic and statistics, a reliability approach provides a rational basis for analysis of the randomness in loads and their effects on structures. A novel approach combined SHM systems with reliability method to evaluate the reliability of a cable-stayed bridge instrumented with SHM systems was presented in this paper. In this study, the reliability of the steel girder of the cable-stayed bridge was denoted by failure probability directly instead of reliability index as commonly used. Under the assumption that the probability distributions of the resistance are independent to the responses of structures, a formulation of failure probability was deduced. Then, as a main factor in the formulation, the probability density function (PDF) of the strain at sensor locations based on the monitoring data was evaluated and verified. That Donghai Bridge was taken as an example for the application of the proposed approach followed. In the case study, 4 years' monitoring data since the operation of the SHM systems was processed, and the reliability assessment results were discussed. Finally, the sensitivity and accuracy of the novel approach compared with FORM was discussed.

The Clinical Interview Schedule-Revised (CIS-R)-Malay Version, Clinical Validation.

PubMed

Subramaniam, Kavitha; Krishnaswamy, Saroja; Jemain, Abdul Aziz; Hamid, Abdul; Patel, Vikram

2006-01-01

Use of instruments or questionnaires in different cultural settings without proper validation can result in inaccurate results. Issues like reliability, validity, feasibility and acceptability should be considered in the use of an instrument. The study aims to determine the usefulness of the CIS-R Malay version in detecting common mental health problems specifically to establish the validity. The CIS-R instrument (PROQSY* format) was translated through the back translation process into Malay. Inter rater reliability was established for raters who were medical students. Cases and controls for the study were psychiatric in patients, out patient and relatives or friends accompanying the patients to the clinic or visiting the inpatients. The Malay version of CIS-R was administered to all cases and controls. All cases and controls involved in the study were rated by psychiatrists for psychiatric morbidity using the SCID as a guideline. Specificity and sensitivity of the CIS-R to the assessment by the psychiatrist were determined. The Malay version of CIS-R showed 100% sensitivity and 96.15% specificity at a cut off score of 9. The CIS-R can be a useful instrument for clinical and research use in the Malaysian population for diagnosing common mental disorders like depression and anxiety.

On-time reliability impacts of advanced traveler information services (ATIS) : Washington, DC case study

DOT National Transportation Integrated Search

1998-09-01

Emissions Management Using ITS Technology report summarizes and interprets the results of three Intelligent Transportation Systems (ITS) Field Operational Tests (FOTs) that evaluated the use of emerging technologies to help authorities measure emissi...

Differential reliability : probabilistic engineering applied to wood members in bending-tension

Treesearch

Stanley K. Suddarth; Frank E. Woeste; William L. Galligan

1978-01-01

Reliability analysis is a mathematical technique for appraising the design and materials of engineered structures to provide a quantitative estimate of probability of failure. Two or more cases which are similar in all respects but one may be analyzed by this method; the contrast between the probabilities of failure for these cases allows strong analytical focus on the...

Inter-rater and test-retest reliability of quality assessments by novice student raters using the Jadad and Newcastle-Ottawa Scales.

PubMed

Oremus, Mark; Oremus, Carolina; Hall, Geoffrey B C; McKinnon, Margaret C

2012-01-01

Quality assessment of included studies is an important component of systematic reviews. The authors investigated inter-rater and test-retest reliability for quality assessments conducted by inexperienced student raters. Student raters received a training session on quality assessment using the Jadad Scale for randomised controlled trials and the Newcastle-Ottawa Scale (NOS) for observational studies. Raters were randomly assigned into five pairs and they each independently rated the quality of 13-20 articles. These articles were drawn from a pool of 78 papers examining cognitive impairment following electroconvulsive therapy to treat major depressive disorder. The articles were randomly distributed to the raters. Two months later, each rater re-assessed the quality of half of their assigned articles. McMaster Integrative Neuroscience Discovery and Study Program. 10 students taking McMaster Integrative Neuroscience Discovery and Study Program courses. The authors measured inter-rater reliability using κ and the intraclass correlation coefficient type 2,1 or ICC(2,1). The authors measured test-retest reliability using ICC(2,1). Inter-rater reliability varied by scale question. For the six-item Jadad Scale, question-specific κs ranged from 0.13 (95% CI -0.11 to 0.37) to 0.56 (95% CI 0.29 to 0.83). The ranges were -0.14 (95% CI -0.28 to 0.00) to 0.39 (95% CI -0.02 to 0.81) for the NOS cohort and -0.20 (95% CI -0.49 to 0.09) to 1.00 (95% CI 1.00 to 1.00) for the NOS case-control. For overall scores on the six-item Jadad Scale, ICC(2,1)s for inter-rater and test-retest reliability (accounting for systematic differences between raters) were 0.32 (95% CI 0.08 to 0.52) and 0.55 (95% CI 0.41 to 0.67), respectively. Corresponding ICC(2,1)s for the NOS cohort were -0.19 (95% CI -0.67 to 0.35) and 0.62 (95% CI 0.25 to 0.83), and for the NOS case-control, the ICC(2,1)s were 0.46 (95% CI -0.13 to 0.92) and 0.83 (95% CI 0.48 to 0.95). Inter-rater reliability was generally poor to fair and test-retest reliability was fair to excellent. A pilot rating phase following rater training may be one way to improve agreement.

Harmonization Process and Reliability Assessment of Anthropometric Measurements in the Elderly EXERNET Multi-Centre Study

PubMed Central

Gómez-Cabello, Alba; Vicente-Rodríguez, Germán; Albers, Ulrike; Mata, Esmeralda; Rodriguez-Marroyo, Jose A.; Olivares, Pedro R.; Gusi, Narcis; Villa, Gerardo; Aznar, Susana; Gonzalez-Gross, Marcela; Casajús, Jose A.; Ara, Ignacio

2012-01-01

Background The elderly EXERNET multi-centre study aims to collect normative anthropometric data for old functionally independent adults living in Spain. Purpose To describe the standardization process and reliability of the anthropometric measurements carried out in the pilot study and during the final workshop, examining both intra- and inter-rater errors for measurements. Materials and Methods A total of 98 elderly from five different regions participated in the intra-rater error assessment, and 10 different seniors living in the city of Toledo (Spain) participated in the inter-rater assessment. We examined both intra- and inter-rater errors for heights and circumferences. Results For height, intra-rater technical errors of measurement (TEMs) were smaller than 0.25 cm. For circumferences and knee height, TEMs were smaller than 1 cm, except for waist circumference in the city of Cáceres. Reliability for heights and circumferences was greater than 98% in all cases. Inter-rater TEMs were 0.61 cm for height, 0.75 cm for knee-height and ranged between 2.70 and 3.09 cm for the circumferences measured. Inter-rater reliabilities for anthropometric measurements were always higher than 90%. Conclusion The harmonization process, including the workshop and pilot study, guarantee the quality of the anthropometric measurements in the elderly EXERNET multi-centre study. High reliability and low TEM may be expected when assessing anthropometry in elderly population. PMID:22860013

The Role of Psychometrics in Individual Differences Research in Cognition: A Case Study of the AX-CPT

PubMed Central

Cooper, Shelly R.; Gonthier, Corentin; Barch, Deanna M.; Braver, Todd S.

2017-01-01

Investigating individual differences in cognition requires addressing questions not often thought about in standard experimental designs, especially regarding the psychometric properties of the task. Using the AX-CPT cognitive control task as a case study example, we address four concerns that one may encounter when researching the topic of individual differences in cognition. First, we demonstrate the importance of variability in task scores, which in turn directly impacts reliability, particularly when comparing correlations in different populations. Second, we demonstrate the importance of variability and reliability for evaluating potential failures to replicate predicted correlations, even within the same population. Third, we demonstrate how researchers can turn to evaluating psychometric properties as a way of evaluating the feasibility of utilizing the task in new settings (e.g., online administration). Lastly, we show how the examination of psychometric properties can help researchers make informed decisions when designing a study, such as determining the appropriate number of trials for a task. PMID:28928690

A Study of Sustainable Assessment Theory in Higher Education Tutorials

ERIC Educational Resources Information Center

Beck, Robert J.; Skinner, William F.; Schwabrow, Lynsey A.

2013-01-01

A study of sustainable assessment theory in nine tutorial courses at four colleges demonstrated that three long-term learning outcomes improved: Independence, Intellectual Maturity and Creativity. Eight of 10 traits associated with these outcomes were validated through internal reliability, faculty and student rubrics, and faculty case studies…

Parametric Mass Reliability Study

NASA Technical Reports Server (NTRS)

Holt, James P.

2014-01-01

The International Space Station (ISS) systems are designed based upon having redundant systems with replaceable orbital replacement units (ORUs). These ORUs are designed to be swapped out fairly quickly, but some are very large, and some are made up of many components. When an ORU fails, it is replaced on orbit with a spare; the failed unit is sometimes returned to Earth to be serviced and re-launched. Such a system is not feasible for a 500+ day long-duration mission beyond low Earth orbit. The components that make up these ORUs have mixed reliabilities. Components that make up the most mass-such as computer housings, pump casings, and the silicon board of PCBs-typically are the most reliable. Meanwhile components that tend to fail the earliest-such as seals or gaskets-typically have a small mass. To better understand the problem, my project is to create a parametric model that relates both the mass of ORUs to reliability, as well as the mass of ORU subcomponents to reliability.

A GA based penalty function technique for solving constrained redundancy allocation problem of series system with interval valued reliability of components

NASA Astrophysics Data System (ADS)

Gupta, R. K.; Bhunia, A. K.; Roy, D.

2009-10-01

In this paper, we have considered the problem of constrained redundancy allocation of series system with interval valued reliability of components. For maximizing the overall system reliability under limited resource constraints, the problem is formulated as an unconstrained integer programming problem with interval coefficients by penalty function technique and solved by an advanced GA for integer variables with interval fitness function, tournament selection, uniform crossover, uniform mutation and elitism. As a special case, considering the lower and upper bounds of the interval valued reliabilities of the components to be the same, the corresponding problem has been solved. The model has been illustrated with some numerical examples and the results of the series redundancy allocation problem with fixed value of reliability of the components have been compared with the existing results available in the literature. Finally, sensitivity analyses have been shown graphically to study the stability of our developed GA with respect to the different GA parameters.

Optimizing preventive maintenance policy: A data-driven application for a light rail braking system.

PubMed

Corman, Francesco; Kraijema, Sander; Godjevac, Milinko; Lodewijks, Gabriel

2017-10-01

This article presents a case study determining the optimal preventive maintenance policy for a light rail rolling stock system in terms of reliability, availability, and maintenance costs. The maintenance policy defines one of the three predefined preventive maintenance actions at fixed time-based intervals for each of the subsystems of the braking system. Based on work, maintenance, and failure data, we model the reliability degradation of the system and its subsystems under the current maintenance policy by a Weibull distribution. We then analytically determine the relation between reliability, availability, and maintenance costs. We validate the model against recorded reliability and availability and get further insights by a dedicated sensitivity analysis. The model is then used in a sequential optimization framework determining preventive maintenance intervals to improve on the key performance indicators. We show the potential of data-driven modelling to determine optimal maintenance policy: same system availability and reliability can be achieved with 30% maintenance cost reduction, by prolonging the intervals and re-grouping maintenance actions.

Optimizing preventive maintenance policy: A data-driven application for a light rail braking system

PubMed Central

Corman, Francesco; Kraijema, Sander; Godjevac, Milinko; Lodewijks, Gabriel

2017-01-01

This article presents a case study determining the optimal preventive maintenance policy for a light rail rolling stock system in terms of reliability, availability, and maintenance costs. The maintenance policy defines one of the three predefined preventive maintenance actions at fixed time-based intervals for each of the subsystems of the braking system. Based on work, maintenance, and failure data, we model the reliability degradation of the system and its subsystems under the current maintenance policy by a Weibull distribution. We then analytically determine the relation between reliability, availability, and maintenance costs. We validate the model against recorded reliability and availability and get further insights by a dedicated sensitivity analysis. The model is then used in a sequential optimization framework determining preventive maintenance intervals to improve on the key performance indicators. We show the potential of data-driven modelling to determine optimal maintenance policy: same system availability and reliability can be achieved with 30% maintenance cost reduction, by prolonging the intervals and re-grouping maintenance actions. PMID:29278245

A proposal to study the experience of female scientists in Mexico: Physicists as a case study

NASA Astrophysics Data System (ADS)

Martínez, Amalia; Blázquez, Norma; Gómez, Yolanda; Vales, Caridad; Meza-Montes, Lilia

2013-03-01

Although the design of public policies to support and improve the status and opportunities for female scientists requires reliable data, studies of this type have not been done in Mexico. We present a proposal to conduct such a study at the national level, with physicists as a test group.

Occupational exposure to respirable crystalline silica and chronic non-malignant renal disease: systematic review and meta-analysis.

PubMed

Möhner, Matthias; Pohrt, Anne; Gellissen, Johannes

2017-10-01

While occupational exposure to respirable silica is known to lead to lung disease, most notably silicosis, its association with chronic kidney disease is unclear. This review explores the association between occupational exposure to respirable silica and chronic non-malignant renal disease such as glomerulonephritis. The evidence has been collected and compiled. Possible sources of bias are thoroughly discussed. Cohort studies with silica exposure and case-control studies of renal disease were searched in PubMed until January 2015. Two authors independently abstracted data; any disagreement was resolved by consulting a third reviewer. A meta-analysis was performed to evaluate the association to silica exposure. A total of 23 cohort and four case-control studies were included in the analysis. The meta-analysis of cohort studies yielded elevated overall SMRs for renal disease. Some studies, however, included dose-response analyses, most of which did not show a positive trend. The approaches and results of the case-control studies were very heterogeneous. While the studies of cohorts exposed to silica found elevated SMRs for renal disease, no clear evidence of a dose-response relationship emerged. The elevated risk may be attributed to diagnostic and methodological issues. In order to permit a reliable estimation of a possible causal link, exposed cohorts should be monitored for renal disease, as the information from mortality studies is hardly reliable in this field.

Does a web-based feedback training program result in improved reliability in clinicians' ratings of the Global Assessment of Functioning (GAF) Scale?

PubMed

Støre-Valen, Jakob; Ryum, Truls; Pedersen, Geir A F; Pripp, Are H; Jose, Paul E; Karterud, Sigmund

2015-09-01

The Global Assessment of Functioning (GAF) Scale is used in routine clinical practice and research to estimate symptom and functional severity and longitudinal change. Concerns about poor interrater reliability have been raised, and the present study evaluated the effect of a Web-based GAF training program designed to improve interrater reliability in routine clinical practice. Clinicians rated up to 20 vignettes online, and received deviation scores as immediate feedback (i.e., own scores compared with expert raters) after each rating. Growth curves of absolute SD scores across the vignettes were modeled. A linear mixed effects model, using the clinician's deviation scores from expert raters as the dependent variable, indicated an improvement in reliability during training. Moderation by content of scale (symptoms; functioning), scale range (average; extreme), previous experience with GAF rating, profession, and postgraduate training were assessed. Training reduced deviation scores for inexperienced GAF raters, for individuals in clinical professions other than nursing and medicine, and for individuals with no postgraduate specialization. In addition, training was most beneficial for cases with average severity of symptoms compared with cases with extreme severity. The results support the use of Web-based training with feedback routines as a means to improve the reliability of GAF ratings performed by clinicians in mental health practice. These results especially pertain to clinicians in mental health practice who do not have a masters or doctoral degree. (c) 2015 APA, all rights reserved.

Assessment of a spectral domain OCT segmentation software in a retrospective cohort study of exudative AMD patients.

PubMed

Tilleul, Julien; Querques, Giuseppe; Canoui-Poitrine, Florence; Leveziel, Nicolas; Souied, Eric H

2013-01-01

To assess the ability of the Spectralis optical coherence tomography (OCT) segmentation software to identify the inner limiting membrane and Bruch's membrane in exudative age-related macular degeneration (AMD) patients. Thirty-eight eyes of 38 naive exudative AMD patients were retrospectively included. They all had a complete ophthalmologic examination including Spectralis OCT at baseline, at month 1 and 2. Reliability of the segmentation software was assessed by 2 ophthalmologists. Reliability of the segmentation software was defined as good if both inner limiting membrane and Bruch's membrane were correctly drawn. A total of 38 patients charts were reviewed (114 scans). The inner limiting membrane was correctly drawn by the segmentation software in 114/114 spectral domain OCT scans (100%). Conversely, Bruch's membrane was correctly drawn in 59/114 scans (51.8%). The software was less reliable in locating Bruch's membrane in case of pigment epithelium detachment (PED) than without PED (42.5 vs. 73.5%, respectively; p = 0.049), but its reliability was not associated with SRF or CME (p = 0.55 and p = 0.10, respectively). Segmentation of the inner limiting membrane was constantly trustworthy but Bruch's membrane segmentation was poorly reliable using the automatic Spectralis segmentation software. Based on this software, evaluation of retinal thickness may be incorrect, particularly in case of PED. PED is effectively an important parameter which is not included when measuring retinal thickness. Copyright © 2012 S. Karger AG, Basel.

Reliability Correction for Functional Connectivity: Theory and Implementation

PubMed Central

Mueller, Sophia; Wang, Danhong; Fox, Michael D.; Pan, Ruiqi; Lu, Jie; Li, Kuncheng; Sun, Wei; Buckner, Randy L.; Liu, Hesheng

2016-01-01

Network properties can be estimated using functional connectivity MRI (fcMRI). However, regional variation of the fMRI signal causes systematic biases in network estimates including correlation attenuation in regions of low measurement reliability. Here we computed the spatial distribution of fcMRI reliability using longitudinal fcMRI datasets and demonstrated how pre-estimated reliability maps can correct for correlation attenuation. As a test case of reliability-based attenuation correction we estimated properties of the default network, where reliability was significantly lower than average in the medial temporal lobe and higher in the posterior medial cortex, heterogeneity that impacts estimation of the network. Accounting for this bias using attenuation correction revealed that the medial temporal lobe’s contribution to the default network is typically underestimated. To render this approach useful to a greater number of datasets, we demonstrate that test-retest reliability maps derived from repeated runs within a single scanning session can be used as a surrogate for multi-session reliability mapping. Using data segments with different scan lengths between 1 and 30 min, we found that test-retest reliability of connectivity estimates increases with scan length while the spatial distribution of reliability is relatively stable even at short scan lengths. Finally, analyses of tertiary data revealed that reliability distribution is influenced by age, neuropsychiatric status and scanner type, suggesting that reliability correction may be especially important when studying between-group differences. Collectively, these results illustrate that reliability-based attenuation correction is an easily implemented strategy that mitigates certain features of fMRI signal nonuniformity. PMID:26493163

Best Practices for Evaluating the Capability of Nondestructive Evaluation (NDE) and Structural Health Monitoring (SHM) Techniques for Damage Characterization (Post-Print)

DTIC Science & Technology

2016-02-10

a wide range of part, environmental and damage conditions. Best practices of using models are presented for both an eddy current NDE sizing and...to assess the reliability of NDE and SHM characterization capability. Best practices of using models are presented for both an eddy current NDE... EDDY CURRENT NDE CASE STUDY An eddy current crack sizing case study is presented to highlight examples of some of these complex characteristics of

Uncovertebral joint injury in cervical facet dislocation: the headphones sign.

PubMed

Palmieri, Francesco; Cassar-Pullicino, Victor N; Dell'Atti, Claudia; Lalam, Radhesh K; Tins, Bernhard J; Tyrrell, Prudencia N M; McCall, Iain W

2006-06-01

The purpose of our study is to demonstrate the uncovertebral mal-alignment as a reliable indirect sign of cervical facet joint dislocation. We examined the uncovertebral axial plane alignment of 12 patients with unilateral and bilateral cervical facet joint dislocation (UCFJD and BCFJD, respectively), comparing its frequency to the reverse hamburger bun sign on CT and MR axial images. Of the seven cases with BCFJD, five clearly demonstrated the diagnostic reverse facet joint hamburger bun sign on CT and MR images, but in two cases this sign was not detectable. In the five cases with UCFJD, four demonstrated the reverse hamburger bun sign on both CT and MRI. In one case the reverse hamburger bun sign was not seen adequately with either image modality, but the facet dislocation was identified on sagittal imaging. The uncovertebral mal-alignment was detected in all 12 cases. Normally, the two components of the uncovertebral joint enjoy a concentric relationship that in the axial plane is reminiscent of the relationship of headphones with the wearer's head. We name this appearance the 'headphones' sign. Radiologists should be aware of the headphones sign as a reliable indicator of facet joint dislocation on axial imaging used in the assessment of cervical spine injuries.

Study of structural reliability of existing concrete structures

NASA Astrophysics Data System (ADS)

Druķis, P.; Gaile, L.; Valtere, K.; Pakrastiņš, L.; Goremikins, V.

2017-10-01

Structural reliability of buildings has become an important issue after the collapse of a shopping center in Riga 21.11.2013, caused the death of 54 people. The reliability of a building is the practice of designing, constructing, operating, maintaining and removing buildings in ways that ensure maintained health, ward suffered injuries or death due to use of the building. Evaluation and improvement of existing buildings is becoming more and more important. For a large part of existing buildings, the design life has been reached or will be reached in the near future. The structures of these buildings need to be reassessed in order to find out whether the safety requirements are met. The safety requirements provided by the Eurocodes are a starting point for the assessment of safety. However, it would be uneconomical to require all existing buildings and structures to comply fully with these new codes and corresponding safety levels, therefore the assessment of existing buildings differs with each design situation. This case study describes the simple and practical procedure of determination of minimal reliability index β of existing concrete structures designed by different codes than Eurocodes and allows to reassess the actual reliability level of different structural elements of existing buildings under design load.

Approximate Bayesian algorithm to estimate the basic reproduction number in an influenza pandemic using arrival times of imported cases.

PubMed

Chong, Ka Chun; Zee, Benny Chung Ying; Wang, Maggie Haitian

2018-04-10

In an influenza pandemic, arrival times of cases are a proxy of the epidemic size and disease transmissibility. Because of intense surveillance of travelers from infected countries, detection is more rapid and complete than on local surveillance. Travel information can provide a more reliable estimation of transmission parameters. We developed an Approximate Bayesian Computation algorithm to estimate the basic reproduction number (R 0 ) in addition to the reporting rate and unobserved epidemic start time, utilizing travel, and routine surveillance data in an influenza pandemic. A simulation was conducted to assess the sampling uncertainty. The estimation approach was further applied to the 2009 influenza A/H1N1 pandemic in Mexico as a case study. In the simulations, we showed that the estimation approach was valid and reliable in different simulation settings. We also found estimates of R 0 and the reporting rate to be 1.37 (95% Credible Interval [CI]: 1.26-1.42) and 4.9% (95% CI: 0.1%-18%), respectively, in the 2009 influenza pandemic in Mexico, which were robust to variations in the fixed parameters. The estimated R 0 was consistent with that in the literature. This method is useful for officials to obtain reliable estimates of disease transmissibility for strategic planning. We suggest that improvements to the flow of reporting for confirmed cases among patients arriving at different countries are required. Copyright © 2018 Elsevier Ltd. All rights reserved.

Assessing Reliability of Medical Record Reviews for the Detection of Hospital Adverse Events.

PubMed

Ock, Minsu; Lee, Sang-il; Jo, Min-Woo; Lee, Jin Yong; Kim, Seon-Ha

2015-09-01

The purpose of this study was to assess the inter-rater reliability and intra-rater reliability of medical record review for the detection of hospital adverse events. We conducted two stages retrospective medical records review of a random sample of 96 patients from one acute-care general hospital. The first stage was an explicit patient record review by two nurses to detect the presence of 41 screening criteria (SC). The second stage was an implicit structured review by two physicians to identify the occurrence of adverse events from the positive cases on the SC. The inter-rater reliability of two nurses and that of two physicians were assessed. The intra-rater reliability was also evaluated by using test-retest method at approximately two weeks later. In 84.2% of the patient medical records, the nurses agreed as to the necessity for the second stage review (kappa, 0.68; 95% confidence interval [CI], 0.54 to 0.83). In 93.0% of the patient medical records screened by nurses, the physicians agreed about the absence or presence of adverse events (kappa, 0.71; 95% CI, 0.44 to 0.97). When assessing intra-rater reliability, the kappa indices of two nurses were 0.54 (95% CI, 0.31 to 0.77) and 0.67 (95% CI, 0.47 to 0.87), whereas those of two physicians were 0.87 (95% CI, 0.62 to 1.00) and 0.37 (95% CI, -0.16 to 0.89). In this study, the medical record review for detecting adverse events showed intermediate to good level of inter-rater and intra-rater reliability. Well organized training program for reviewers and clearly defining SC are required to get more reliable results in the hospital adverse event study.

Reliability of the ADI-R for the Single Case-Part II: Clinical versus Statistical Significance

ERIC Educational Resources Information Center

Cicchetti, Domenic V.; Lord, Catherine; Koenig, Kathy; Klin, Ami; Volkmar, Fred R.

2014-01-01

In an earlier investigation, the authors assessed the reliability of the ADI-R when multiple clinicians evaluated a single case, here a female 3 year old toddler suspected of having an autism spectrum disorder (Cicchetti et al. in "J Autism Dev Disord" 38:764-770, 2008). Applying the clinical criteria of Cicchetti and Sparrow ("Am J…

Clinical and Prognostic Features of Erionite-Induced Malignant Mesothelioma

PubMed Central

Demirer, Ersin; Ghattas, Christian F.; Radwan, Mohamed O.

2015-01-01

This review analytically examines the published data for erionite-related malignant pleural mesothelioma (E-MPM) and any data to support a genetically predisposed mechanism to erionite fiber carcinogenesis. Adult patients of age ≥18 years with erionite-related pleural diseases and genetically predisposed mechanisms to erionite carcinogenesis were included, while exclusion criteria included asbestos- or tremolite-related pleural diseases. The search was limited to human studies though not limited to a specific timeframe. A total of 33 studies (31042 patients) including 22 retrospective studies, 6 prospective studies, and 5 case reports were reviewed. E-MPM developed in some subjects with high exposures to erionite, though not all. Chest CT was more reliable in detecting various pleural changes in E-MPM than chest X-ray, and pleural effusion was the most common finding in E-MPM cases, by both tests. Bronchoalveolar lavage remains a reliable and relatively less invasive technique. Chemotherapy with cisplatin and mitomycin can be administered either alone or following surgery. Erionite has been the culprit of numerous malignant mesothelioma cases in Europe and even in North America. Erionite has a higher degree of carcinogenicity with possible genetic transmission of erionite susceptibility in an autosomal dominant fashion. Therapeutic management for E-MPM remains very limited, and cure of the disease is extremely rare. PMID:25683976

Reproducibility of African giant pouched rats detecting Mycobacterium tuberculosis.

PubMed

Ellis, Haylee; Mulder, Christiaan; Valverde, Emilio; Poling, Alan; Edwards, Timothy

2017-04-24

African pouched rats sniffing sputum samples provided by local clinics have significantly increased tuberculosis case findings in Tanzania and Mozambique. The objective of this study was to determine the reproducibility of rat results. Over an 18-month period 11,869 samples were examined by the rats. Intra-rater reliability was assessed through Yule's Q. Inter-rater reliability was assessed with Krippendorff's alpha. Intra-rater reliability was high, with a mean Yule's Q of 0.9. Inter-rater agreement was fair, with Krippendorf's alpha ranging from 0.15 to 0.45. Both Intra- and Inter-rater reliability was independent of the sex of the animals, but they were positively correlated with age. Both intra- and inter-rater agreement was lowest for samples designated as smear-negative by the clinics. Overall, the reproducibility of tuberculosis detection rat results was fair and diagnostic results were therefore independent of the rats used.

Modelling utility-scale wind power plants. Part 2: Capacity credit

NASA Astrophysics Data System (ADS)

Milligan, Michael R.

2000-10-01

As the worldwide use of wind turbine generators in utility-scale applications continues to increase, it will become increasingly important to assess the economic and reliability impact of these intermittent resources. Although the utility industry appears to be moving towards a restructured environment, basic economic and reliability issues will continue to be relevant to companies involved with electricity generation. This article is the second in a two-part series that addresses modelling approaches and results that were obtained in several case studies and research projects at the National Renewable Energy Laboratory (NREL). This second article focuses on wind plant capacity credit as measured with power system reliability indices. Reliability-based methods of measuring capacity credit are compared with wind plant capacity factor. The relationship between capacity credit and accurate wind forecasting is also explored. Published in 2000 by John Wiley & Sons, Ltd.

Fault-tolerant building-block computer study

NASA Technical Reports Server (NTRS)

Rennels, D. A.

1978-01-01

Ultra-reliable core computers are required for improving the reliability of complex military systems. Such computers can provide reliable fault diagnosis, failure circumvention, and, in some cases serve as an automated repairman for their host systems. A small set of building-block circuits which can be implemented as single very large integration devices, and which can be used with off-the-shelf microprocessors and memories to build self checking computer modules (SCCM) is described. Each SCCM is a microcomputer which is capable of detecting its own faults during normal operation and is described to communicate with other identical modules over one or more Mil Standard 1553A buses. Several SCCMs can be connected into a network with backup spares to provide fault-tolerant operation, i.e. automated recovery from faults. Alternative fault-tolerant SCCM configurations are discussed along with the cost and reliability associated with their implementation.

The reliability of cause-of-death coding in The Netherlands.

PubMed

Harteloh, Peter; de Bruin, Kim; Kardaun, Jan

2010-08-01

Cause-of-death statistics are a major source of information for epidemiological research or policy decisions. Information on the reliability of these statistics is important for interpreting trends in time or differences between populations. Variations in coding the underlying cause of death could hinder the attribution of observed differences to determinants of health. Therefore we studied the reliability of cause-of-death statistics in The Netherlands. We performed a double coding study. Death certificates from the month of May 2005 were coded again in 2007. Each death certificate was coded manually by four coders. Reliability was measured by calculating agreement between coders (intercoder agreement) and by calculating the consistency of each individual coder in time (intracoder agreement). Our analysis covered an amount of 10,833 death certificates. The intercoder agreement of four coders on the underlying cause of death was 78%. In 2.2% of the cases coders agreed on a change of the code assigned in 2005. The (mean) intracoder agreement of four coders was 89%. Agreement was associated with the specificity of the ICD-10 code (chapter, three digits, four digits), the age of the deceased, the number of coders and the number of diseases reported on the death certificate. The reliability of cause-of-death statistics turned out to be high (>90%) for major causes of death such as cancers and acute myocardial infarction. For chronic diseases, such as diabetes and renal insufficiency, reliability was low (<70%). The reliability of cause-of-death statistics varies by ICD-10 code/chapter. A statistical office should provide coders with (additional) rules for coding diseases with a low reliability and evaluate these rules regularly. Users of cause-of-death statistics should exercise caution when interpreting causes of death with a low reliability. Studies of reliability should take into account the number of coders involved and the number of codes on a death certificate.

Probabilistic simulation of the human factor in structural reliability

NASA Astrophysics Data System (ADS)

Chamis, Christos C.; Singhal, Surendra N.

1994-09-01

The formal approach described herein computationally simulates the probable ranges of uncertainties for the human factor in probabilistic assessments of structural reliability. Human factors such as marital status, professional status, home life, job satisfaction, work load, and health are studied by using a multifactor interaction equation (MFIE) model to demonstrate the approach. Parametric studies in conjunction with judgment are used to select reasonable values for the participating factors (primitive variables). Subsequently performed probabilistic sensitivity studies assess the suitability of the MFIE as well as the validity of the whole approach. Results show that uncertainties range from 5 to 30 percent for the most optimistic case, assuming 100 percent for no error (perfect performance).

Probabilistic Simulation of the Human Factor in Structural Reliability

NASA Technical Reports Server (NTRS)

Chamis, Christos C.; Singhal, Surendra N.

1994-01-01

The formal approach described herein computationally simulates the probable ranges of uncertainties for the human factor in probabilistic assessments of structural reliability. Human factors such as marital status, professional status, home life, job satisfaction, work load, and health are studied by using a multifactor interaction equation (MFIE) model to demonstrate the approach. Parametric studies in conjunction with judgment are used to select reasonable values for the participating factors (primitive variables). Subsequently performed probabilistic sensitivity studies assess the suitability of the MFIE as well as the validity of the whole approach. Results show that uncertainties range from 5 to 30 percent for the most optimistic case, assuming 100 percent for no error (perfect performance).

Forecasting malaria cases using climatic factors in delhi, India: a time series analysis.

PubMed

Kumar, Varun; Mangal, Abha; Panesar, Sanjeet; Yadav, Geeta; Talwar, Richa; Raut, Deepak; Singh, Saudan

2014-01-01

Background. Malaria still remains a public health problem in developing countries and changing environmental and climatic factors pose the biggest challenge in fighting against the scourge of malaria. Therefore, the study was designed to forecast malaria cases using climatic factors as predictors in Delhi, India. Methods. The total number of monthly cases of malaria slide positives occurring from January 2006 to December 2013 was taken from the register maintained at the malaria clinic at Rural Health Training Centre (RHTC), Najafgarh, Delhi. Climatic data of monthly mean rainfall, relative humidity, and mean maximum temperature were taken from Regional Meteorological Centre, Delhi. Expert modeler of SPSS ver. 21 was used for analyzing the time series data. Results. Autoregressive integrated moving average, ARIMA (0,1,1) (0,1,0)(12), was the best fit model and it could explain 72.5% variability in the time series data. Rainfall (P value = 0.004) and relative humidity (P value = 0.001) were found to be significant predictors for malaria transmission in the study area. Seasonal adjusted factor (SAF) for malaria cases shows peak during the months of August and September. Conclusion. ARIMA models of time series analysis is a simple and reliable tool for producing reliable forecasts for malaria in Delhi, India.

High-resolution chromosomal microarrays in prenatal diagnosis significantly increase diagnostic power.

PubMed

Oneda, Beatrice; Baldinger, Rosa; Reissmann, Regina; Reshetnikova, Irina; Krejci, Pavel; Masood, Rahim; Ochsenbein-Kölble, Nicole; Bartholdi, Deborah; Steindl, Katharina; Morotti, Denise; Faranda, Marzia; Baumer, Alessandra; Asadollahi, Reza; Joset, Pascal; Niedrist, Dunja; Breymann, Christian; Hebisch, Gundula; Hüsler, Margaret; Mueller, René; Prentl, Elke; Wisser, Josef; Zimmermann, Roland; Rauch, Anita

2014-06-01

The objective of this study was to determine for the first time the reliability and the diagnostic power of high-resolution microarray testing in routine prenatal diagnostics. We applied high-resolution chromosomal microarray testing in 464 cytogenetically normal prenatal samples with any indication for invasive testing. High-resolution testing revealed a diagnostic yield of 6.9% and 1.6% in cases of fetal ultrasound anomalies and cases of advanced maternal age (AMA), respectively, which is similar to previous studies using low-resolution microarrays. In three (0.6%) additional cases with an indication of AMA, an aberration in susceptibility risk loci was detected. Moreover, one case (0.2%) showed an X-linked aberration in a female fetus, a finding relevant for future family planning. We found the rate of cases, in which the parents had to be tested for interpretation of unreported copy number variants (3.7%), and the rate of remaining variants of unknown significance (0.4%) acceptably low. Of note, these findings did not cause termination of pregnancy after expert genetic counseling. The 0.4% rate of confined placental mosaicism was similar to that observed by conventional karyotyping and notably involved a case of placental microdeletion. High-resolution prenatal microarray testing is a reliable technique that increases diagnostic yield by at least 17.3% when compared with conventional karyotyping, without an increase in the frequency of variants of uncertain significance. © 2014 John Wiley & Sons, Ltd.

A behaviourally anchored rating scale for evaluating the use of the WHO surgical safety checklist: development and initial evaluation of the WHOBARS.

PubMed

Devcich, Daniel A; Weller, Jennifer; Mitchell, Simon J; McLaughlin, Scott; Barker, Lauren; Rudolph, Jenny W; Raemer, Daniel B; Zammert, Martin; Singer, Sara J; Torrie, Jane; Frampton, Chris Ma; Merry, Alan F

2016-10-01

Realising the full potential of the WHO Surgical Safety Checklist (SSC) to reduce perioperative harm requires the constructive engagement of all operating room (OR) team members during its administration. To facilitate research on SSC implementation, a valid and reliable instrument is needed for measuring OR team behaviours during its administration. We developed a behaviourally anchored rating scale (BARS) for this purpose. We used a modified Delphi process, involving 16 subject matter experts, to compile a BARS with behavioural domains applicable to all three phases of the SSC. We evaluated the instrument in 80 adult OR cases and 30 simulated cases using two medical student raters and seven expert raters, respectively. Intraclass correlation coefficients were calculated to assess inter-rater reliability. Internal consistency and instrument discrimination were explored. Sample size estimates for potential study designs using the instrument were calculated. The Delphi process resulted in a BARS instrument (the WHOBARS) with five behavioural domains. Intraclass correlation coefficients calculated from the OR cases exceeded 0.80 for 80% of the instrument's domains across the SSC phases. The WHOBARS showed high internal consistency across the three phases of the SSC and ability to discriminate among surgical cases in both clinical and simulated settings. Fewer than 20 cases per group would be required to show a difference of 1 point between groups in studies of the SSC, where α=0.05 and β=0.8. We have developed a generic instrument for comprehensively rating the administration of the SSC and informing initiatives to realise its full potential. We have provided data supporting its capacity for discrimination, internal consistency and inter-rater reliability. Further psychometric evaluation is warranted. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

40 CFR 57.405 - Formulation, approval, and implementation of requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... study shall be submitted after the end of the worst case three-month period as a part of the next semi... study demonstrating that the SCS will prevent violations of the NAAQS in the smelter's DLA at all times. The reliability study shall include a comprehensive analysis of the system's operation during one or...

Studies of advanced glycation end products and oxidation biomarkers for type 2 diabetes.

PubMed

Chiu, Chung-Jung; Rabbani, Naila; Rowan, Sheldon; Chang, Min-Lee; Sawyer, Sherilyn; Hu, Frank B; Willett, Walter; Thornalley, Paul J; Anwar, Attia; Bar, Liliana; Kang, Jae H; Taylor, Allen

2018-05-02

Advanced glycation end products (AGEs) are formed upon nonenzymatic reactions of sugars or their metabolites with proteins and other cellular constituents. Many AGEs are long lived. Recent findings suggest that AGEs may predict diabetes and its complications and thus may warrant further study. The objective of this study was to assess the validity of our experimental procedures for measuring AGEs in stored blood sample and to conduct a pilot study for developing AGE biomarkers for diabetes and/or age-related changes of glucose metabolism. We conducted a reliability study of the samples and methods using liquid chromatography-tandem mass spectrometry (LC-MS)/MS assays for 10 AGEs (including methylglyoxal-derived hydroimidazolone (MG-H1), glucosepane (GSP) and two oxidation measures, in stored repository blood samples from the Nurses' Health Study and the Health Professionals Follow-up Study. We also analyzed data relating blood GSP levels to type 2 diabetes status in a case-control study (25 cases and 15 controls). Among the AGEs, GSP, and MG-H1 showed the highest reliability across the various measures: reliability in duplicate samples and stability with delayed processing and storage over 1-2 year period. Furthermore, plasma GSP was associated with older age (P = 0.04) and type 2 diabetes status (age-adjusted P = 0.0475). Our findings suggest that analysis of these AGEs may be developed as biomarkers for diabetes and/or age-related changes of glucose metabolism. © 2018 BioFactors, 2018. © 2018 International Union of Biochemistry and Molecular Biology.

Probabilistic Solar Energetic Particle Models

NASA Technical Reports Server (NTRS)

Adams, James H., Jr.; Dietrich, William F.; Xapsos, Michael A.

2011-01-01

To plan and design safe and reliable space missions, it is necessary to take into account the effects of the space radiation environment. This is done by setting the goal of achieving safety and reliability with some desired level of confidence. To achieve this goal, a worst-case space radiation environment at the required confidence level must be obtained. Planning and designing then proceeds, taking into account the effects of this worst-case environment. The result will be a mission that is reliable against the effects of the space radiation environment at the desired confidence level. In this paper we will describe progress toward developing a model that provides worst-case space radiation environments at user-specified confidence levels. We will present a model for worst-case event-integrated solar proton environments that provide the worst-case differential proton spectrum. This model is based on data from IMP-8 and GOES spacecraft that provide a data base extending from 1974 to the present. We will discuss extending this work to create worst-case models for peak flux and mission-integrated fluence for protons. We will also describe plans for similar models for helium and heavier ions.

Self-reinforced bioresorbable poly-L/DL-lactide [SR-P(L/DL)LA] 70/30 miniplates and miniscrews are reliable for fixation of anterior mandibular fractures: a pilot study.

PubMed

Ylikontiola, Leena; Sundqvuist, Kai; Sàndor, George K B; Törmälä, Pertti; Ashammakhi, Nureddin

2004-03-01

Bioresorbable osteofixation devices are being increasingly used in orthognathic surgery and in cases of trauma to avoid problems associated with conventional metal osteofixation devices. The aim of this clinical study was to assess the reliability and efficacy of bioresorbable self-reinforced poly-L/DL-lactide (SR-P(L/DL)LA 70/30) plates and screws in the fixation of mandibular fractures in adults. Ten patients (20 to 49 years old) with isolated anterior mandibular parasymphyseal fractures were treated by means of open reduction and internal fixation using SR-P(L/DL)LA 70/30 bioresorbable plates and screws. During the minimum of 6 months of follow-up, no problems were encountered except for 1 case where a plate became exposed intraorally and infected. This required debridement and later excision of the exposed part of the plate. Despite this setback the fractured bone healed well. SR-P(L/DL)LA 70/30 plates and screws are reliable for internal fixation of anterior mandibular fractures in adults. Proper soft tissue coverage should be ensured to avoid plate exposure. Should implant exposure occur, it might be necessary to excise the exposed part after fracture healing (6-8 weeks postoperatively).

School Principals in Southern Thailand: Exploring Trust with Community Leaders during Conflict

ERIC Educational Resources Information Center

Brooks, Melanie C.

2015-01-01

This article reports findings from a case study of school principals in Southern Thailand who work in areas targeted by Muslim separatist groups. Data were gathered and analyzed using a conceptual framework that conceived of trust as five interrelated constructs: benevolence, honesty, openness, reliability, and competence. This study builds on…

Actual innocence: is death different?

PubMed

Acker, James R

2009-01-01

Supreme Court jurisprudence relies heavily on the premise that "death is different" from other criminal sanctions, and that capital cases entail commensurately demanding standards of reliability. Although invoked most frequently with respect to sentencing, both precedent and logic suggest that heightened reliability applies as well to guilt determination in capital trials. Nevertheless, recurrent and highly visible wrongful convictions in capital cases have affected public opinion, contributed to a precipitous decline in new death sentences, and led to calls for reforms designed to guard against the risk of executing innocent persons. This article examines the implications of the "death is different" doctrine for the problem of wrongful convictions in both capital and non-capital cases. It argues that innovations designed to enhance reliability in the special context of death-penalty prosecutions are important in their own right, but relevant new safeguards also should extend to criminal cases generally, where innocent people are similarly at risk and wrongful convictions are far more prevalent. (c) 2009 John Wiley & Sons, Ltd.

Fiber Access Networks: Reliability Analysis and Swedish Broadband Market

NASA Astrophysics Data System (ADS)

Wosinska, Lena; Chen, Jiajia; Larsen, Claus Popp

Fiber access network architectures such as active optical networks (AONs) and passive optical networks (PONs) have been developed to support the growing bandwidth demand. Whereas particularly Swedish operators prefer AON, this may not be the case for operators in other countries. The choice depends on a combination of technical requirements, practical constraints, business models, and cost. Due to the increasing importance of reliable access to the network services, connection availability is becoming one of the most crucial issues for access networks, which should be reflected in the network owner's architecture decision. In many cases protection against failures is realized by adding backup resources. However, there is a trade off between the cost of protection and the level of service reliability since improving reliability performance by duplication of network resources (and capital expenditures CAPEX) may be too expensive. In this paper we present the evolution of fiber access networks and compare reliability performance in relation to investment and management cost for some representative cases. We consider both standard and novel architectures for deployment in both sparsely and densely populated areas. While some recent works focused on PON protection schemes with reduced CAPEX the current and future effort should be put on minimizing the operational expenditures (OPEX) during the access network lifetime.

14 CFR 13.223 - Standard of proof.

Code of Federal Regulations, 2011 CFR

2011-01-01

... only if the decision or ruling is supported by, and in accordance with, the reliable, probative, and... prove the party's case or defense by a preponderance of reliable, probative, and substantial evidence. ...

14 CFR 13.223 - Standard of proof.

Code of Federal Regulations, 2010 CFR

2010-01-01

... only if the decision or ruling is supported by, and in accordance with, the reliable, probative, and... prove the party's case or defense by a preponderance of reliable, probative, and substantial evidence. ...

Predicting What Will Happen When You Intervene.

PubMed

Cartwright, Nancy; Hardie, Jeremy

2017-01-01

This paper offers some rules of thumb that practicing social workers can use for case studies that aim to construct, albeit not fully and never entirely reliably, models designed to help predict what will happen if they intervene in specific ways to help this particular client, here and now. We call these 'ex ante case-specific causal models'. 'Ex ante' because they are for before-the-fact prediction of what the likely effects of proposed actions are. 'Case-specific' because we are not concerned with studies that provide evidence for some general conclusion but rather with using what general and local knowledge one can get to predict what will happen to a specific client in the real settings in which they live. 'Causal' because this kind of case study aims to trace out as best possible the web of causal processes that will be responsible for what happens. In this sense our case studies resemble post facto realist evaluations.

Interrelation Between Safety Factors and Reliability

NASA Technical Reports Server (NTRS)

Elishakoff, Isaac; Chamis, Christos C. (Technical Monitor)

2001-01-01

An evaluation was performed to establish relationships between safety factors and reliability relationships. Results obtained show that the use of the safety factor is not contradictory to the employment of the probabilistic methods. In many cases the safety factors can be directly expressed by the required reliability levels. However, there is a major difference that must be emphasized: whereas the safety factors are allocated in an ad hoc manner, the probabilistic approach offers a unified mathematical framework. The establishment of the interrelation between the concepts opens an avenue to specify safety factors based on reliability. In cases where there are several forms of failure, then the allocation of safety factors should he based on having the same reliability associated with each failure mode. This immediately suggests that by the probabilistic methods the existing over-design or under-design can be eliminated. The report includes three parts: Part 1-Random Actual Stress and Deterministic Yield Stress; Part 2-Deterministic Actual Stress and Random Yield Stress; Part 3-Both Actual Stress and Yield Stress Are Random.

Multi-mode reliability-based design of horizontal curves.

PubMed

Essa, Mohamed; Sayed, Tarek; Hussein, Mohamed

2016-08-01

Recently, reliability analysis has been advocated as an effective approach to account for uncertainty in the geometric design process and to evaluate the risk associated with a particular design. In this approach, a risk measure (e.g. probability of noncompliance) is calculated to represent the probability that a specific design would not meet standard requirements. The majority of previous applications of reliability analysis in geometric design focused on evaluating the probability of noncompliance for only one mode of noncompliance such as insufficient sight distance. However, in many design situations, more than one mode of noncompliance may be present (e.g. insufficient sight distance and vehicle skidding at horizontal curves). In these situations, utilizing a multi-mode reliability approach that considers more than one failure (noncompliance) mode is required. The main objective of this paper is to demonstrate the application of multi-mode (system) reliability analysis to the design of horizontal curves. The process is demonstrated by a case study of Sea-to-Sky Highway located between Vancouver and Whistler, in southern British Columbia, Canada. Two noncompliance modes were considered: insufficient sight distance and vehicle skidding. The results show the importance of accounting for several noncompliance modes in the reliability model. The system reliability concept could be used in future studies to calibrate the design of various design elements in order to achieve consistent safety levels based on all possible modes of noncompliance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Overview of the SAE G-11 RMSL (Reliability, Maintainability, Supportability, and Logistics) Division Activities and Technical Projects

NASA Technical Reports Server (NTRS)

Singhal, Surendra N.

2003-01-01

The SAE G-11 RMSL (Reliability, Maintainability, Supportability, and Logistics) Division activities include identification and fulfillment of joint industry, government, and academia needs for development and implementation of RMSL technologies. Four Projects in the Probabilistic Methods area and two in the area of RMSL have been identified. These are: (1) Evaluation of Probabilistic Technology - progress has been made toward the selection of probabilistic application cases. Future effort will focus on assessment of multiple probabilistic softwares in solving selected engineering problems using probabilistic methods. Relevance to Industry & Government - Case studies of typical problems encountering uncertainties, results of solutions to these problems run by different codes, and recommendations on which code is applicable for what problems; (2) Probabilistic Input Preparation - progress has been made in identifying problem cases such as those with no data, little data and sufficient data. Future effort will focus on developing guidelines for preparing input for probabilistic analysis, especially with no or little data. Relevance to Industry & Government - Too often, we get bogged down thinking we need a lot of data before we can quantify uncertainties. Not True. There are ways to do credible probabilistic analysis with little data; (3) Probabilistic Reliability - probabilistic reliability literature search has been completed along with what differentiates it from statistical reliability. Work on computation of reliability based on quantification of uncertainties in primitive variables is in progress. Relevance to Industry & Government - Correct reliability computations both at the component and system level are needed so one can design an item based on its expected usage and life span; (4) Real World Applications of Probabilistic Methods (PM) - A draft of volume 1 comprising aerospace applications has been released. Volume 2, a compilation of real world applications of probabilistic methods with essential information demonstrating application type and timehost savings by the use of probabilistic methods for generic applications is in progress. Relevance to Industry & Government - Too often, we say, 'The Proof is in the Pudding'. With help from many contributors, we hope to produce such a document. Problem is - not too many people are coming forward due to proprietary nature. So, we are asking to document only minimum information including problem description, what method used, did it result in any savings, and how much?; (5) Software Reliability - software reliability concept, program, implementation, guidelines, and standards are being documented. Relevance to Industry & Government - software reliability is a complex issue that must be understood & addressed in all facets of business in industry, government, and other institutions. We address issues, concepts, ways to implement solutions, and guidelines for maximizing software reliability; (6) Maintainability Standards - maintainability/serviceability industry standard/guidelines and industry best practices and methodologies used in performing maintainability/ serviceability tasks are being documented. Relevance to Industry & Government - Any industry or government process, project, and/or tool must be maintained and serviced to realize the life and performance it was designed for. We address issues and develop guidelines for optimum performance & life.

Translation, adaptation and inter-rater reliability of the administration manual for the Fugl-Meyer assessment.

PubMed

Michaelsen, Stella M; Rocha, André S; Knabben, Rodrigo J; Rodrigues, Luciano P; Fernandes, Claudia G C

2011-01-01

Recently, the reliability of the Brazilian version of the Fugl-Meyer Assessment (FMA) was assessed through the scoring given according to observations made by a single evaluator who applied the test. When different raters apply the scale, the reliability may depend on the interpretation given to the assessment sheet. In such cases, a clear administration manual is essential for ensuring homogeneity of application. To translate and adapt the French Canadian version of the FMA administration manual into Brazilian Portuguese and to evaluate the inter-rater reliability when different evaluators apply the FMA on the basis of the information contained in the manual. Eighteen adults (59±10 years) with chronic hemiparesis (38±35 months after a stroke) took part in this study. Eight patients participated in the first part of the study and 10 in the second part. Based on analyzing the results from part 1, an adapted version was developed, in which information and photos were added to illustrate the positions of the patient and evaluator. The inter-rater reliability was assessed using the intraclass correlation coefficient (ICC). The reliability of the FMA based on the adapted version of the manual was excellent for the total motor scores for the upper limbs (ICC=0.98) and lower limbs (ICC=0.90), as well as for movement sense (ICC=0.98) and upper and lower-limb passive range of motion (ICC=0.84 and 0.90, respectively). The reliability was moderate for tactile sensitivity (0.75). The joint pain assessment presented low reliability. The results showed that, except for pain assessment, application of the FMA based on the adapted version of the application manual for Brazilian Portuguese presented adequate inter-rater reliability.

Intraoperative use of indocyanine green angiography for selecting the more reliable perforator of the anterolateral thigh flap: A comparison study.

PubMed

La Padula, Simone; Hersant, Barbara; Meningaud, Jean Paul

2018-03-30

Anatomical variability of anterolateral thigh flap (ALT) perforators has been reported. The aim of this study is to assess if the use of intraoperative indocyanine green angiography (iICGA) can help surgeons to choose the ALT flap best perforator to be preserved. A retrospective study was conducted in 28 patients with open tibial fracture, following a road traffic crash, who had undergone ALT flap. Patients were classified into two groups: ICGA group (iICGA was used to select the more reliable perforator) and control group. The mean tissue loss size of the ICGA group (n = 13, 11 men and 2 women, mean age: 52 ± 6 years) was of 16.6 cm × 12.2 cm. The mean defect size of the control group (n = 15, 14 men and 1 women, mean age: 50 ± 5.52 years) was of 15.3 cm × 11.1 cm. Statistical analysis was performed to analyze and compare the results. ICGA allowed preserving only the most functional perforator, that provided the best ALT flap perfusion in 10 out of the 13 cases (77%). ICGA allowed a significant operative time reduction (160 ± 23 vs. 202 ± 48 minutes; P < .001). One case of distal necrosis was observed in the ICGA group (mean follow-up 12.3 months), while partial skin necrosis occurred in three cases of the control group (mean follow-up 13.1 months); P = .35. No additional coverage was required and a successful bone healing was observed in both groups. These findings suggest that iICGA is an effective method that allows to select the most reliable ALT flap perforators and to reduce operative time. © 2018 Wiley Periodicals, Inc.

Evaluation of previously embolized intracranial aneurysms: inter-and intra-rater reliability among neurosurgeons and interventional neuroradiologists.

PubMed

Zuckerman, Scott L; Lakomkin, Nikita; Magarik, Jordan A; Vargas, Jan; Stephens, Marcus; Akinpelu, Babatunde; Spiotta, Alejandro M; Ahmed, Azam; Arthur, Adam S; Fiorella, David; Hanel, Ricardo; Hirsch, Joshua A; Hui, Ferdinand K; James, Robert F; Kallmes, David F; Meyers, Philip M; Niemann, David B; Rasmussen, Peter; Turner, Raymond D; Welch, Babu G; Mocco, J

2018-05-01

The angiographic evaluation of previously coiled aneurysms can be difficult yet remains critical for determining re-treatment. The main objective of this study was to determine the inter-rater reliability for both the Raymond Scale and per cent embolization among a group of neurointerventionalists evaluating previously embolized aneurysms. A panel of 15 neurointerventionalists examined 92 distinct cases of immediate post-coil embolization and 1 year post-embolization angiographs. Each case was presented four times throughout the study, along with alterations in demographics in order to evaluate intra-rater reliability. All respondents were asked to provide the per cent embolization (0-100%) and Raymond Scale grade (1-3) for each aneurysm. Inter-rater reliability was evaluated by computing weighted kappa values (for the Raymond Scale) and intraclass correlation coefficients (ICC) for per cent embolization. 10 neurosurgeons and 5 interventional neuroradiologists evaluated 368 simulated cases. The agreement among all readers employing the Raymond Scale was fair (κ=0.35) while concordance in per cent embolization was good (ICC=0.64). Clinicians with fewer than 10 years of experience demonstrated a significantly greater level of agreement than the group with greater than 10 years (κ=0.39 and ICC=0.70 vs κ=0.28 and ICC=0.58). When the same aneurysm was presented multiple times, clinicians demonstrated excellent consistency when assessing per cent embolization (ICC=0.82), but moderate agreement when employing the Raymond classification (κ=0.58). Identifying the per cent embolization in previously coiled aneurysms resulted in good inter- and intra-rater agreement, regardless of years of experience. The strong agreement among providers employing per cent embolization may make it a valuable tool for embolization assessment in this patient population. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Failure-Time Distribution Of An m-Out-of-n System

NASA Technical Reports Server (NTRS)

Scheuer, Ernest M.

1988-01-01

Formulas for reliability extended to more general cases. Useful in analyses of reliabilities of practical systems and structures, especially of redundant systems of identical components, among which operating loads distributed equally.

Event-based internet biosurveillance: relation to epidemiological observation

PubMed Central

2012-01-01

Background The World Health Organization (WHO) collects and publishes surveillance data and statistics for select diseases, but traditional methods of gathering such data are time and labor intensive. Event-based biosurveillance, which utilizes a variety of Internet sources, complements traditional surveillance. In this study we assess the reliability of Internet biosurveillance and evaluate disease-specific alert criteria against epidemiological data. Methods We reviewed and compared WHO epidemiological data and Argus biosurveillance system data for pandemic (H1N1) 2009 (April 2009 – January 2010) from 8 regions and 122 countries to: identify reliable alert criteria among 15 Argus-defined categories; determine the degree of data correlation for disease progression; and assess timeliness of Internet information. Results Argus generated a total of 1,580 unique alerts; 5 alert categories generated statistically significant (p < 0.05) correlations with WHO case count data; the sum of these 5 categories was highly correlated with WHO case data (r = 0.81, p < 0.0001), with expected differences observed among the 8 regions. Argus reported first confirmed cases on the same day as WHO for 21 of the first 64 countries reporting cases, and 1 to 16 days (average 1.5 days) ahead of WHO for 42 of those countries. Conclusion Confirmed pandemic (H1N1) 2009 cases collected by Argus and WHO methods returned consistent results and confirmed the reliability and timeliness of Internet information. Disease-specific alert criteria provide situational awareness and may serve as proxy indicators to event progression and escalation in lieu of traditional surveillance data; alerts may identify early-warning indicators to another pandemic, preparing the public health community for disease events. PMID:22709988

Infant polysomnography: reliability and validity of infant arousal assessment.

PubMed

Crowell, David H; Kulp, Thomas D; Kapuniai, Linda E; Hunt, Carl E; Brooks, Lee J; Weese-Mayer, Debra E; Silvestri, Jean; Ward, Sally Davidson; Corwin, Michael; Tinsley, Larry; Peucker, Mark

2002-10-01

Infant arousal scoring based on the Atlas Task Force definition of transient EEG arousal was evaluated to determine (1). whether transient arousals can be identified and assessed reliably in infants and (2). whether arousal and no-arousal epochs scored previously by trained raters can be validated reliably by independent sleep experts. Phase I for inter- and intrarater reliability scoring was based on two datasets of sleep epochs selected randomly from nocturnal polysomnograms of healthy full-term, preterm, idiopathic apparent life-threatening event cases, and siblings of Sudden Infant Death Syndrome infants of 35 to 64 weeks postconceptional age. After training, test set 1 reliability was assessed and discrepancies identified. After retraining, test set 2 was scored by the same raters to determine interrater reliability. Later, three raters from the trained group rescored test set 2 to assess inter- and intrarater reliabilities. Interrater and intrarater reliability kappa's, with 95% confidence intervals, ranged from substantial to almost perfect levels of agreement. Interrater reliabilities for spontaneous arousals were initially moderate and then substantial. During the validation phase, 315 previously scored epochs were presented to four sleep experts to rate as containing arousal or no-arousal events. Interrater expert agreements were diverse and considered as noninterpretable. Concordance in sleep experts' agreements, based on identification of the previously sampled arousal and no-arousal epochs, was used as a secondary evaluative technique. Results showed agreement by two or more experts on 86% of the Collaborative Home Infant Monitoring Evaluation Study arousal scored events. Conversely, only 1% of the Collaborative Home Infant Monitoring Evaluation Study-scored no-arousal epochs were rated as an arousal. In summary, this study presents an empirically tested model with procedures and criteria for attaining improved reliability in transient EEG arousal assessments in infants using the modified Atlas Task Force standards. With training based on specific criteria, substantial inter- and intrarater agreement in identifying infant arousals was demonstrated. Corroborative validation results were too disparate for meaningful interpretation. Alternate evaluation based on concordance agreements supports reliance on infant EEG criteria for assessment. Results mandate additional confirmatory validation studies with specific training on infant EEG arousal assessment criteria.

Reliability analysis of the objective structured clinical examination using generalizability theory.

PubMed

Trejo-Mejía, Juan Andrés; Sánchez-Mendiola, Melchor; Méndez-Ramírez, Ignacio; Martínez-González, Adrián

2016-01-01

The objective structured clinical examination (OSCE) is a widely used method for assessing clinical competence in health sciences education. Studies using this method have shown evidence of validity and reliability. There are no published studies of OSCE reliability measurement with generalizability theory (G-theory) in Latin America. The aims of this study were to assess the reliability of an OSCE in medical students using G-theory and explore its usefulness for quality improvement. An observational cross-sectional study was conducted at National Autonomous University of Mexico (UNAM) Faculty of Medicine in Mexico City. A total of 278 fifth-year medical students were assessed with an 18-station OSCE in a summative end-of-career final examination. There were four exam versions. G-theory with a crossover random effects design was used to identify the main sources of variance. Examiners, standardized patients, and cases were considered as a single facet of analysis. The exam was applied to 278 medical students. The OSCE had a generalizability coefficient of 0.93. The major components of variance were stations, students, and residual error. The sites and the versions of the tests had minimum variance. Our study achieved a G coefficient similar to that found in other reports, which is acceptable for summative tests. G-theory allows the estimation of the magnitude of multiple sources of error and helps decision makers to determine the number of stations, test versions, and examiners needed to obtain reliable measurements.

Reliability analysis of the objective structured clinical examination using generalizability theory.

PubMed

Trejo-Mejía, Juan Andrés; Sánchez-Mendiola, Melchor; Méndez-Ramírez, Ignacio; Martínez-González, Adrián

2016-01-01

Background The objective structured clinical examination (OSCE) is a widely used method for assessing clinical competence in health sciences education. Studies using this method have shown evidence of validity and reliability. There are no published studies of OSCE reliability measurement with generalizability theory (G-theory) in Latin America. The aims of this study were to assess the reliability of an OSCE in medical students using G-theory and explore its usefulness for quality improvement. Methods An observational cross-sectional study was conducted at National Autonomous University of Mexico (UNAM) Faculty of Medicine in Mexico City. A total of 278 fifth-year medical students were assessed with an 18-station OSCE in a summative end-of-career final examination. There were four exam versions. G-theory with a crossover random effects design was used to identify the main sources of variance. Examiners, standardized patients, and cases were considered as a single facet of analysis. Results The exam was applied to 278 medical students. The OSCE had a generalizability coefficient of 0.93. The major components of variance were stations, students, and residual error. The sites and the versions of the tests had minimum variance. Conclusions Our study achieved a G coefficient similar to that found in other reports, which is acceptable for summative tests. G-theory allows the estimation of the magnitude of multiple sources of error and helps decision makers to determine the number of stations, test versions, and examiners needed to obtain reliable measurements.

[Significance of roentgen cinematography in the diagnosis of functional disorders of the pharyngo-esophageal junction].

PubMed

Augustiny, N; wolfensberger, M; Brühlmann, W

1984-12-01

Dysfunction of the pharyngo-oesophageal sphincter may escape detection by clinical examination, endoscopy, and routine barium studies. Cineradiographic examination of 300 patients with unexplained dysphagia revealed 57 cases of pharyngo-oesophageal dysfunction. In 25 cases an underlying disorder could be found, and 32 cases were considered idiopathic. Radiologically 3 types of dysfunction may be distinguished, namely late opening, incomplete relaxation, and early contraction of the pharyngo-oesophageal sphincter. Cineradiography was found to be an easy and reliable method of detecting pharyngo-oesophageal sphincter dysfunction.

Time to competency, reliability of flexible transnasal laryngoscopy by training level: a pilot study.

PubMed

Brook, Christopher D; Platt, Michael P; Russell, Kimberly; Grillone, Gregory A; Aliphas, Avner; Noordzij, J Pieter

2015-05-01

To determine the progression of flexible transnasal laryngoscopy reliability and competency in otolaryngology residency training. Prospective case control study. Academic otolaryngology department. Medical students, otolaryngology residents, and otolaryngology attending physicians. Fourteen otolaryngology residents from PGY-1 to PGY-5 and 3 attending otolaryngologists viewed 25 selected and digitally recorded flexible transnasal laryngoscopies. The evaluators were asked to rate 13 items relating to abnormalities in the oropharynx, hypopharynx, larynx, and subglottis. The level of concern and level of comfort with the diagnosis were assessed. Intraclass correlations were calculated for each topic and by level of training to determine reliability within each class and compare competency versus attending interpretations. Intraclass correlation of residents compared to attending physicians demonstrated significant improvements by year for left and right vocal fold immobility, subglottic stenosis, laryngeal mass, left and right vocal cord abnormalities, and level of concern. Additionally, pooled vocal cord mobility and pooled results in categories with good attending reliability demonstrated stepwise improvement as well. For these categories, resident reliability was found to be statistically similar to attending physicians in all categories by PGY-3. There were no trends for base of tongue abnormalities, pharyngeal abnormalities, and pharyngeal and hypopharyngeal masses. Resident competency for flexible transnasal laryngoscopy progresses during residency to reliability with attending otolaryngologists by the PGY-3 year over key facets of the examination. © American Academy of Otolaryngology-Head and Neck Surgery Foundation 2015.

Dedifferentiated liposarcoma of the oral floor: A case study and literature review of 50 cases of head and neck neoplasm.

PubMed

Nimura, Fumikazu; Nakasone, Toshiyuki; Matsumoto, Hirofumi; Maruyama, Tessho; Matayoshi, Akira; Maruyama, Nobuyuki; Yoshimi, Naoki; Arasaki, Akira; Nishihara, Kazuhide

2018-05-01

Dedifferentiated liposarcoma (DDLS) has a relatively poor prognosis, however this neoplasm rarely occurs in the head and neck. To date, no definite protocol has been established for the diagnosis and treatment of head and neck DDLS. The present study reports the case of a 69-year-old male patient with DDLS of the oral floor. To the best of our knowledge, this is the first documented case of oral floor DDLS. In addition, this is the first reported case with the development of a second primary malignancy following the treatment of head and neck DDLS. A literature review of 50 cases of head and neck DDLS revealed that preoperative biopsy is not reliable for the diagnosis of these tumors and an accurate pathological diagnosis with total resection is preferred.

Dedifferentiated liposarcoma of the oral floor: A case study and literature review of 50 cases of head and neck neoplasm

PubMed Central

Nimura, Fumikazu; Nakasone, Toshiyuki; Matsumoto, Hirofumi; Maruyama, Tessho; Matayoshi, Akira; Maruyama, Nobuyuki; Yoshimi, Naoki; Arasaki, Akira; Nishihara, Kazuhide

2018-01-01

Dedifferentiated liposarcoma (DDLS) has a relatively poor prognosis, however this neoplasm rarely occurs in the head and neck. To date, no definite protocol has been established for the diagnosis and treatment of head and neck DDLS. The present study reports the case of a 69-year-old male patient with DDLS of the oral floor. To the best of our knowledge, this is the first documented case of oral floor DDLS. In addition, this is the first reported case with the development of a second primary malignancy following the treatment of head and neck DDLS. A literature review of 50 cases of head and neck DDLS revealed that preoperative biopsy is not reliable for the diagnosis of these tumors and an accurate pathological diagnosis with total resection is preferred. PMID:29740489

Development and validation of a novel questionnaire for self-determination of the range of motion of wrist and elbow.

PubMed

Schnetzke, Marc; Schüler, Svenja; Keil, Holger; Aytac, Sara; Studier-Fischer, Stefan; Grützner, Paul-Alfred; Guehring, Thorsten

2016-07-26

The aim of this study was to develop and validate a novel self-administered questionnaire for assessing the patient's own range of motion (ROM) of the wrist and the elbow. In a prospective clinical study from January 2015 to June 2015, 101 consecutive patients were evaluated with a novel, self-administered, diagram-based, wrist motion assessment score (W-MAS) and elbow motion assessment score (E-MAS). The questionnaire was statistically evaluated for test-retest reliability, patient-physician agreement, comparison with healthy population, and influence of covariates (age, gender, affected side and involvement in workers' compensation cases). Assessment of patient-physician agreement demonstrated almost perfect agreement (k > 0.80) with regard to six out of eight items. There was substantial agreement with regard to two items: elbow extension (k = 0.76) and pronation (k = 0.75). The assessment of the test-retest reliability revealed at least substantial agreement (k = 0.70). The questionnaire revealed a high discriminative power when comparing the healthy population with the study group (p = 0.007 or lower for every item). Age, gender, affected side and involvement in workers' compensation cases did not in general significantly influence the patient-physician agreement for the questionnaire. The W-MAS and E-MAS are valid and reliable self-administered questionnaires that provide a high level of patient-physician agreement for the assessments of wrist and elbow ROM. Diagnostic study, Level II.

Clinico-radiological diagnosis and grading of rapidly progressive osteoarthritis of the hip.

PubMed

Zazgyva, Ancuţa; Gurzu, Simona; Gergely, István; Jung, Ioan; Roman, Ciprian O; Pop, Tudor S

2017-03-01

Due to the current lack of standard definitions for rapidly progressive osteoarthritis of the hip (RPOH) in the literature, this observational study aimed to describe new diagnostic criteria and a grading system for the disease.From a consecutive series of patients undergoing total hip replacement, 2 groups were selected: 1 with RPOH and 1 with primary hip osteoarthritis (POH), and their clinical, paraclinical, and demographic data were compared. The newly proposed clinico-radiological diagnostic criteria are based on characteristics of pain, joint mobility, and radiological assessment. The radiological grading system's inter- and intraobserver reliability was assessed through serial evaluations by 2 blinded reviewers.From the total 863 cases, 82 cases (9.5%) of RPOH were identified and compared with 107 cases of POH. Mean age and disease bilaterality were similar, with a predominance of female patients in the RPOH group (P = 0.03). There were significant differences between the 2 groups in disease onset and aggravation, and intraoperative blood loss. The grading system showed significant inter- and intraobserver agreement (weighted kappa 0.93, and 0.89).Our study presents distinctive, easily recognizable clinico-radiological characteristics of RPOH and confirmed the inter- and intraobserver reliability of the newly proposed grading system.

Monitoring and validation of decentralised water and wastewater systems for increased uptake.

PubMed

Sharma, A K; Cook, S; Chong, M N

2013-01-01

Decentralised water and wastewater systems are being implemented to meet growing demand for municipal services either in combination with centralised systems or as standalone systems. In Australia, there has been increased investment in decentralised water and wastewater systems in response to the capacity constraints of existing centralised systems, an extended period of below average rainfall, uncertainly in traditional water sources due to potential climate change impacts, and the need to reduce the environmental impact of urban development. The implementation of decentralised water systems as a mainstream practice at different development scales is impeded by the knowledge gaps on their actual performance in a range of development types and settings. As the wide-spread uptake of these approaches in modern cities is relatively new compared to centralised approaches, there is limited information available on their planning, design, implementation, reliability and robustness. This paper presents a number of case studies where monitoring studies are under way to validate the performance of decentralised water and wastewater systems. The results from these case studies show the yield and reliability of these decentralised systems, as well as the associated energy demand and ecological footprint. The outputs from these case studies, and other monitoring studies, are important in improving decentralised system design guidelines and developing industry wide management norms for the operation and maintenance of decentralised systems.

On-time reliability impacts of advanced traveler information services (ATIS) : Washington, DC case study, executive summary

DOT National Transportation Integrated Search

1999-05-01

This report documents the development and testing of a Surveillance and Delay Advisory System (SDAS) for application in congested rural areas. SDAS included several techniques that could be used on rural highways to give travelers advance information...

Improving precision of forage yield trials: A case study

USDA-ARS?s Scientific Manuscript database

Field-based agronomic and genetic research relies heavily on the data generated from field evaluations. Therefore, it is imperative to optimize the precision of yield estimates in cultivar evaluation trials to make reliable selections. Experimental error in yield trials is sensitive to several facto...

Inter-rater reliability of the German version of the Nurses' Global Assessment of Suicide Risk scale.

PubMed

Kozel, Bernd; Grieser, Manuela; Abderhalden, Christoph; Cutcliffe, John R

2016-10-01

In comparison to the general population, the suicide rates of psychiatric inpatient populations in Germany and Switzerland are very high. An important preventive contribution to the lowering of the suicide rates in mental health care is to ensure that the risk of suicide of psychiatric inpatients is assessed as accurately as possible. While risk-assessment instruments can serve an important function in determining such risk, very few have been translated to German. Therefore, in the present study, we reported on the German version of Nurses' Global Assessment of Suicide Risk (NGASR) scale. After translating the original instrument into German and pretesting the German version, we tested the inter-rater reliability of the instrument. Twelve video case studies were evaluated by 13 raters with the NGASR scale in a 'laboratory' trial. In each case, the observer's agreement was calculated for the single items, the overall scale, the risk levels, and the sum scores. The statistical data analysis was conducted with kappa and AC1 statistics for dichotomous (items, scale) scales. A high-to-very high observers' agreement (AC1: 0.62-1.00, kappa: 0.00-1.00) was determined for 16 items of the German version of the NGASR scale. We conclude that the German version of the NGASR scale is a reliable instrument for evaluating risk factors for suicide. A reliable application in the clinical practise appears to be enhanced by training in the use of the instrument and the right implementation instructions. © 2016 Australian College of Mental Health Nurses Inc.

Transcriptomic resources for environmental risk assessment: a case study in the Venice lagoon.

PubMed

Milan, M; Pauletto, M; Boffo, L; Carrer, C; Sorrentino, F; Ferrari, G; Pavan, L; Patarnello, T; Bargelloni, L

2015-02-01

The development of new resources to evaluate the environmental status is becoming increasingly important representing a key challenge for ocean and coastal management. Recently, the employment of transcriptomics in aquatic toxicology has led to increasing initiatives proposing to integrate eco-toxicogenomics in the evaluation of marine ecosystem health. However, several technical issues need to be addressed before introducing genomics as a reliable tool in regulatory ecotoxicology. The Venice lagoon constitutes an excellent case, in which the assessment of environmental risks derived from the nearby industrial activities represents a crucial task. In this context, the potential role of genomics to assist environmental monitoring was investigated through the definition of reliable gene expression markers associated to chemical contamination in Manila clams, and their subsequent employment for the classification of Venice lagoon areas. Overall, the present study addresses key issues to evaluate the future outlooks of genomics in the environmental monitoring and risk assessment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Transponders as permanent identification markers for domestic ferrets, black-footed ferrets, and other wildlife

USGS Publications Warehouse

Fagerstone, Kathleen A.; Johns, Brad E.

1987-01-01

A 0.05-g transponder implanted subcutaneously was tested to see if it provided a reliable identification method. In laboratory tests 20 domestic ferrets (Mustela putorius furo) received transponders and were monitored for a minimum of 6 months. None showed signs of inflammation, and necropsies conducted at the end of the study showed no scar tissue or transponder migration. Seven of 23 transponders failed during the test because of leakage through the plastic case, and a glass case is now being manufactured that does not have the leakage problem. During mark-recapture studies in September and October 1985, transponders were implanted in 20 black-footed ferrets (M. nigripes), 11 of which were subsequently recaptured and 9 of which were brought into captivity; none showed signs of inflammation. Transponders provide a reliable new method for identifying hard-to-mark wildlife with a unique, permanent number than can be read with the animal in-hand or by remote equipment.

DJ-1 is a reliable serum biomarker for discriminating high-risk endometrial cancer.

PubMed

Di Cello, Annalisa; Di Sanzo, Maddalena; Perrone, Francesca Marta; Santamaria, Gianluca; Rania, Erika; Angotti, Elvira; Venturella, Roberta; Mancuso, Serafina; Zullo, Fulvio; Cuda, Giovanni; Costanzo, Francesco

2017-06-01

New reliable approaches to stratify patients with endometrial cancer into risk categories are highly needed. We have recently demonstrated that DJ-1 is overexpressed in endometrial cancer, showing significantly higher levels both in serum and tissue of patients with high-risk endometrial cancer compared with low-risk endometrial cancer. In this experimental study, we further extended our observation, evaluating the role of DJ-1 as an accurate serum biomarker for high-risk endometrial cancer. A total of 101 endometrial cancer patients and 44 healthy subjects were prospectively recruited. DJ-1 serum levels were evaluated comparing cases and controls and, among endometrial cancer patients, between high- and low-risk patients. The results demonstrate that DJ-1 levels are significantly higher in cases versus controls and in high- versus low-risk patients. The receiver operating characteristic curve analysis shows that DJ-1 has a very good diagnostic accuracy in discriminating endometrial cancer patients versus controls and an excellent accuracy in distinguishing, among endometrial cancer patients, low- from high-risk cases. DJ-1 sensitivity and specificity are the highest when high- and low-risk patients are compared, reaching the value of 95% and 99%, respectively. Moreover, DJ-1 serum levels seem to be correlated with worsening of the endometrial cancer grade and histotype, making it a reliable tool in the preoperative decision-making process.

Reliable fusion of control and sensing in intelligent machines. Thesis

NASA Technical Reports Server (NTRS)

Mcinroy, John E.

1991-01-01

Although robotics research has produced a wealth of sophisticated control and sensing algorithms, very little research has been aimed at reliably combining these control and sensing strategies so that a specific task can be executed. To improve the reliability of robotic systems, analytic techniques are developed for calculating the probability that a particular combination of control and sensing algorithms will satisfy the required specifications. The probability can then be used to assess the reliability of the design. An entropy formulation is first used to quickly eliminate designs not capable of meeting the specifications. Next, a framework for analyzing reliability based on the first order second moment methods of structural engineering is proposed. To ensure performance over an interval of time, lower bounds on the reliability of meeting a set of quadratic specifications with a Gaussian discrete time invariant control system are derived. A case study analyzing visual positioning in robotic system is considered. The reliability of meeting timing and positioning specifications in the presence of camera pixel truncation, forward and inverse kinematic errors, and Gaussian joint measurement noise is determined. This information is used to select a visual sensing strategy, a kinematic algorithm, and a discrete compensator capable of accomplishing the desired task. Simulation results using PUMA 560 kinematic and dynamic characteristics are presented.

Development of Airport Noise Mapping using Matlab Software (Case Study: Adi Soemarmo Airport - Boyolali, Indonesia)

NASA Astrophysics Data System (ADS)

Andarani, Pertiwi; Setiyo Huboyo, Haryono; Setyanti, Diny; Budiawan, Wiwik

2018-02-01

Noise is considered as one of the main environmental impact of Adi Soemarmo International Airport (ASIA), the second largest airport in Central Java Province, Indonesia. In order to manage the noise of airport, airport noise mapping is necessary. However, a model that requires simple input but still reliable was not available in ASIA. Therefore, the objective of this study are to develop model using Matlab software, to verify its reliability by measuring actual noise exposure, and to analyze the area of noise levels‥ The model was developed based on interpolation or extrapolation of identified Noise-Power-Distance (NPD) data. In accordance with Indonesian Government Ordinance No.40/2012, the noise metric used is WECPNL (Weighted Equivalent Continuous Perceived Noise Level). Based on this model simulation, there are residence area in the region of noise level II (1.912 km2) and III (1.16 km2) and 18 school buildings in the area of noise levels I, II, and III. These land-uses are actually prohibited unless noise insulation is equipped. The model using Matlab in the case of Adi Soemarmo International Airport is valid based on comparison of the field measurement (6 sampling points). However, it is important to validate the model again once the case study (the airport) is changed.

Etiologic Ischemic Stroke Phenotypes in the NINDS Stroke Genetics Network

PubMed Central

Ay, Hakan; Arsava, Ethem Murat; Andsberg, Gunnar; Benner, Thomas; Brown, Robert D.; Chapman, Sherita N.; Cole, John W.; Delavaran, Hossein; Dichgans, Martin; Engström, Gunnar; Giralt-Steinhauer, Eva; Grewal, Raji P.; Gwinn, Katrina; Jern, Christina; Jimenez-Conde, Jordi; Jood, Katarina; Katsnelson, Michael; Kissela, Brett; Kittner, Steven J.; Kleindorfer, Dawn O.; Labovitz, Daniel L.; Lanfranconi, Silvia; Lee, Jin-Moo; Lehm, Manuel; Lemmens, Robin; Levi, Chris; Li, Linxin; Lindgren, Arne; Markus, Hugh S.; McArdle, Patrick F.; Melander, Olle; Norrving, Bo; Peddareddygari, Leema Reddy; Pedersén, Annie; Pera, Joanna; Rannikmäe, Kristiina; Rexrode, Kathryn M.; Rhodes, David; Rich, Stephen S.; Roquer, Jaume; Rosand, Jonathan; Rothwell, Peter M.; Rundek, Tatjana; Sacco, Ralph L.; Schmidt, Reinhold; Schürks, Markus; Seiler, Stephan; Sharma, Pankaj; Slowik, Agnieszka; Sudlow, Cathie; Thijs, Vincent; Woodfield, Rebecca; Worrall, Bradford B.; Meschia, James F.

2014-01-01

Background and Purpose NINDS Stroke Genetics Network (SiGN) is an international consortium of ischemic stroke studies that aims to generate high quality phenotype data to identify the genetic basis of etiologic stroke subtypes. This analysis characterizes the etiopathogenetic basis of ischemic stroke and reliability of stroke classification in the consortium. Methods Fifty-two trained and certified adjudicators determined both phenotypic (abnormal test findings categorized in major etiologic groups without weighting towards the most likely cause) and causative ischemic stroke subtypes in 16,954 subjects with imaging-confirmed ischemic stroke from 12 US studies and 11 studies from 8 European countries using the web-based Causative Classification of Stroke System. Classification reliability was assessed with blinded re-adjudication of 1509 randomly selected cases. Results The distribution of etiologic categories varied by study, age, sex, and race (p<0.001 for each). Overall, only 40% to 54% of cases with a given major ischemic stroke etiology (phenotypic subtype) were classified into the same final causative category with high confidence. There was good agreement for both causative (kappa 0.72, 95%CI:0.69-0.75) and phenotypic classifications (kappa 0.73, 95%CI:0.70-0.75). Conclusions This study demonstrates that etiologic subtypes can be determined with good reliability in studies that include investigators with different expertise and background, institutions with different stroke evaluation protocols and geographic location, and patient populations with different epidemiological characteristics. The discordance between phenotypic and causative stroke subtypes highlights the fact that the presence of an abnormality in a stroke patient does not necessarily mean that it is the cause of stroke. PMID:25378430

The London field trial for hoarding disorder.

PubMed

Mataix-Cols, D; Billotti, D; Fernández de la Cruz, L; Nordsletten, A E

2013-04-01

A new diagnostic category, hoarding disorder (HD), has been proposed for inclusion in DSM-5. This study field-tested the validity, reliability and perceived acceptability of the proposed diagnostic criteria for HD. Method Fifty unselected individuals with prominent hoarding behavior and 20 unselected, self-defined 'collectors' participated in thorough psychiatric assessments, involving home visits whenever possible. A semi-structured interview based on the proposed diagnostic criteria for HD was administered and scored by two independent raters. 'True' diagnoses were made by consensus according to the best-estimate diagnosis procedure. The percentage of true positive HD cases (sensitivity) and true negative HD cases (specificity) was calculated, along with inter-rater reliability for the diagnosis and each criterion. Participants were asked about their perceptions of the acceptability, utility and stigma associated with the new diagnosis. Twenty-nine (58%) of the hoarding individuals and none of the collectors fulfilled diagnostic criteria for HD. The sensitivity, specificity and inter-rater reliability of the diagnosis, and of each individual criterion and the specifiers, were excellent. Most participants with HD (96%) felt that creating a new disorder would be very or somewhat acceptable, useful (96%) and not too stigmatizing (59%). The proposed HD criteria are valid, reliable and perceived as acceptable and useful by the sufferers. Crucially, they seem to be sufficiently conservative and unlikely to overpathologize normative behavior. Minor changes in the wording of the criteria are suggested.

Interrater reliability of the Australasian Triage Scale for mental health patients.

PubMed

Creaton, Anne; Liew, Don; Knott, Jonathan; Wright, Melissa

2008-12-01

To evaluate interrater reliability of the Australasian Triage Scale (ATS) for mental health patients in ED. In a prospective descriptive study, triage nurses were shown video vignettes of simulated scenarios of mental health presentations. Trieurs (raters) were asked to allocate an ATS category (rating) to each case. The primary outcome was the degree of interrater reliability for each simulated case. Also assessed were differences between raters or settings, grouped by level of ED activity, state of origin, hospital type and familiarity with appropriate guidelines. Chi-squared analysis was used for independent categorical variables; the Friedman test was used to compare the triage scores between busy and quiet ED scenarios. Ordinal data results were compared using opartchi. All 90 eligible participants were enrolled. The highest interrater concordance was 65.6% whereas the lowest interrater concordance was 53.3%. Significant association occurred between the distribution of triage ratings, ED activity level and the state of origin. A busy ED resulted in the assignment of a more urgent ATS category and decrease in concordance. There is a need to develop and implement a validated, standardized national triage tool for mental health patients. The ATS per se is insufficient to ensure acceptable interrater reliability, particularly during busy periods in the ED, and between states. Given the influence the ATS has on key outcomes, it is imperative for this tool to be robust.

Knowledge Sharing among University Students Facilitated with a Creative Commons Licensing Mechanism: A Case Study in a Programming Course

ERIC Educational Resources Information Center

Liu, Chen-Chung; Lin, Chia-Ching; Chang, Chun-Yi; Chao, Po-Yao

2014-01-01

Creative Commons (CC) mechanism has been suggested as a potential means to foster a reliable environment for online knowledge sharing activity. This study investigates the role of the CC mechanism in supporting knowledge sharing among a group of university students studying programming from the perspectives of social cognitive and social capital…

How the Adoption of the Big-Data Paradigm Affects the Key Factors That Influence the Effectiveness of an Information Assurance (IA) Framework: A Multiple-Case Study

ERIC Educational Resources Information Center

Apple, Benjamin G.

2017-01-01

This qualitative study identified those factors that influence the perceived effectiveness of traditional IA control frameworks. The key factors examined in this study are risk management, governance, access control, privacy protection, integrity, availability, reliability, and usability. The researcher endeavored to determine how the…

Technical Training Requirements of Middle Management in the Greek Textile and Clothing Industries.

ERIC Educational Resources Information Center

Fotinopoulou, K.; Manolopoulos, N.

A case study of 16 companies in the Greek textile and clothing industry elicited the training needs of the industry's middle managers. The study concentrated on large and medium-sized work units, using a lengthy questionnaire. The study found that middle managers increasingly need to solve problems and ensure the reliability of new equipment and…

Detection of early psychotic symptoms: Validation of the Spanish version of the "Symptom Onset in Schizophrenia (SOS) inventory".

PubMed

Mezquida, Gisela; Cabrera, Bibiana; Martínez-Arán, Anabel; Vieta, Eduard; Bernardo, Miguel

2018-03-01

The period of subclinical signs that precedes the onset of psychosis is referred to as the prodrome or high-risk mental state. The "Symptom Onset in Schizophrenia (SOS) inventory" is an instrument to characterize and date the initial symptoms of a psychotic illness. The present study aims to provide reliability and validity data for clinical and research use of the Spanish version of the SOS. Thirty-six participants with a first-episode of psychosis meeting DSM-IV criteria for schizophrenia/schizoaffective/schizophreniform disorder were administered the translated SOS and other clinical assessments. The internal validity, intrarater and interrater reliability were studied. We found strong interrater reliability. To detect the presence/absence of prodromal symptoms, Kappa coefficients ranged between 0.8 and 0.7. Similarly, the raters obtained an excellent level of agreement regarding the onset of each symptom and the duration of symptoms until first treatment (intraclass correlation coefficients between 0.9 and 1.0). Cronbach's alpha was 0.9-1.0 for all the items. The interrater reliability and concurrent validity were also excellent in both cases. This study provides robust psychometric properties of the Spanish version of the SOS. The translated version is adequate in terms of good internal validity, intrarater and interrater reliability, and is as time-efficient as the original version. Copyright © 2017 Elsevier B.V. All rights reserved.

Simulated Surgery-an exam for our time? Summary of the current status and development of the MRCGP Simulated Surgery module.

PubMed

Hawthorne, Kamila; Denney, Mei Ling; Bewick, Mike; Wakeford, Richard

2006-01-01

WHAT IS ALREADY KNOWN IN THIS AREA • The Simulated Surgery module of the MRCGP examination has been shown to be a valid and reliable assessment of clinical consulting skills. WHAT THIS WORK ADDS • This paper describes the further development of the methodology of the Simulated Surgery; showing the type of data analysis currently used to assure its quality and reliability. The measures taken to tighten up case quality are discussed. SUGGESTIONS FOR FUTURE RESEARCH The future development of clinical skills assessments in general practice is discussed. More work is needed on the effectiveness and reliability of lay assessors in complex integrated clinical cases. New methods to test areas that are difficult to reproduces in a simulated environment (such as acute emergencies and cases with the very young or very old) are also needed.

Reliability considerations of a fuel cell backup power system for telecom applications

NASA Astrophysics Data System (ADS)

Serincan, Mustafa Fazil

2016-03-01

A commercial fuel cell backup power unit is tested in real life operating conditions at a base station of a Turkish telecom operator. The fuel cell system responds to 256 of 260 electric power outages successfully, providing the required power to the base station. Reliability of the fuel cell backup power unit is found to be 98.5% at the system level. On the other hand, a qualitative reliability analysis at the component level is carried out. Implications of the power management algorithm on reliability is discussed. Moreover, integration of the backup power unit to the base station ecosystem is reviewed in the context of reliability. Impact of inverter design on the stability of the output power is outlined. Significant current harmonics are encountered when a generic inverter is used. However, ripples are attenuated significantly when a custom design inverter is used. Further, fault conditions are considered for real world case studies such as running out of hydrogen, a malfunction in the system, or an unprecedented operating scheme. Some design guidelines are suggested for hybridization of the backup power unit for an uninterrupted operation.

Effect of bow-type initial imperfection on reliability of minimum-weight, stiffened structural panels

NASA Technical Reports Server (NTRS)

Stroud, W. Jefferson; Krishnamurthy, Thiagaraja; Sykes, Nancy P.; Elishakoff, Isaac

1993-01-01

Computations were performed to determine the effect of an overall bow-type imperfection on the reliability of structural panels under combined compression and shear loadings. A panel's reliability is the probability that it will perform the intended function - in this case, carry a given load without buckling or exceeding in-plane strain allowables. For a panel loaded in compression, a small initial bow can cause large bending stresses that reduce both the buckling load and the load at which strain allowables are exceeded; hence, the bow reduces the reliability of the panel. In this report, analytical studies on two stiffened panels quantified that effect. The bow is in the shape of a half-sine wave along the length of the panel. The size e of the bow at panel midlength is taken to be the single random variable. Several probability density distributions for e are examined to determine the sensitivity of the reliability to details of the bow statistics. In addition, the effects of quality control are explored with truncated distributions.

Illustrated structural application of universal first-order reliability method

NASA Technical Reports Server (NTRS)

Verderaime, V.

1994-01-01

The general application of the proposed first-order reliability method was achieved through the universal normalization of engineering probability distribution data. The method superimposes prevailing deterministic techniques and practices on the first-order reliability method to surmount deficiencies of the deterministic method and provide benefits of reliability techniques and predictions. A reliability design factor is derived from the reliability criterion to satisfy a specified reliability and is analogous to the deterministic safety factor. Its application is numerically illustrated on several practical structural design and verification cases with interesting results and insights. Two concepts of reliability selection criteria are suggested. Though the method was developed to support affordable structures for access to space, the method should also be applicable for most high-performance air and surface transportation systems.

A rapid method to assess grape rust mites on leaves and observations from case studies in western Oregon vineyards

USDA-ARS?s Scientific Manuscript database

A rapid method for extracting eriophyoid mites was adapted from previous studies to provide growers and IPM consultants with a practical, efficient, and reliable tool to monitor for rust mites in vineyards. The rinse in bag (RIB) method allows quick extraction of mites from collected plant parts (sh...

Analysis Testing of Sociocultural Factors Influence on Human Reliability within Sociotechnical Systems: The Algerian Oil Companies.

PubMed

Laidoune, Abdelbaki; Rahal Gharbi, Med El Hadi

2016-09-01

The influence of sociocultural factors on human reliability within an open sociotechnical systems is highlighted. The design of such systems is enhanced by experience feedback. The study was focused on a survey related to the observation of working cases, and by processing of incident/accident statistics and semistructured interviews in the qualitative part. In order to consolidate the study approach, we considered a schedule for the purpose of standard statistical measurements. We tried to be unbiased by supporting an exhaustive list of all worker categories including age, sex, educational level, prescribed task, accountability level, etc. The survey was reinforced by a schedule distributed to 300 workers belonging to two oil companies. This schedule comprises 30 items related to six main factors that influence human reliability. Qualitative observations and schedule data processing had shown that the sociocultural factors can negatively and positively influence operator behaviors. The explored sociocultural factors influence the human reliability both in qualitative and quantitative manners. The proposed model shows how reliability can be enhanced by some measures such as experience feedback based on, for example, safety improvements, training, and information. With that is added the continuous systems improvements to improve sociocultural reality and to reduce negative behaviors.

Compliance of LC50 and NOEC data with Benford's Law: an indication of reliability?

PubMed

de Vries, Pepijn; Murk, Albertinka J

2013-12-01

Reliability of research data is essential, especially when potentially far-reaching conclusions will be based on them. This is also, amongst others, the case for ecotoxicological data used in risk assessment. Currently, several approaches are available to classify the reliability of ecotoxicological data. The process of classification, such as using the Klimisch score, is time-consuming and focuses on the application of standardised protocols and the documentation of the study. The presence of irregularities and the integrity of the performed work, however, are not addressed. The present study shows that Benford's Law, based on the occurrence of first digits following a logarithmic scale, can be applied to ecotoxicity test data for identifying irregularities. This approach is already successfully applied in accounting. Benford's Law can be used as reliability indicator, in addition to existing reliability classifications. The law can be used to efficiently trace irregularities in large data sets of interpolated (no) effect concentrations such as LC50s (possibly the result of data manipulation), without having to evaluate the source of each individual record. Application of the law to systems in which large amounts of toxicity data are registered (e.g., European Commission Regulation concerning the Registration, Evaluation, Authorisation and Restriction of Chemicals) can therefore be valuable. © 2013 Elsevier Inc. All rights reserved.

[Diagnosis of lung embolism. Prospective study].

PubMed

Melcher, G A; Frauchiger, B; Brunner, W; Nager, F

1987-01-31

In a prospective study over the years 1983-1985, 300 cases of acute pulmonary embolism were analyzed in relation to predisposing factors, clinical signs, arterial blood gas analysis and isotope perfusion scanning. Comparison of this prospective study with an earlier retrospective one showed similar results, with the exception of isotope scanning, an investigation which has gained increasing diagnostic reliability (highly suggestive results in 94% of patients with massive pulmonary embolism and in 64% with submassive pulmonary embolism). In two thirds of the cases the diagnosis was established during the first day after hospitalisation. In 10% of the patients pulmonary embolism occurred despite anticoagulant therapy.

Representing Geospatial Environment Observation Capability Information: A Case Study of Managing Flood Monitoring Sensors in the Jinsha River Basin

PubMed Central

Hu, Chuli; Guan, Qingfeng; Li, Jie; Wang, Ke; Chen, Nengcheng

2016-01-01

Sensor inquirers cannot understand comprehensive or accurate observation capability information because current observation capability modeling does not consider the union of multiple sensors nor the effect of geospatial environmental features on the observation capability of sensors. These limitations result in a failure to discover credible sensors or plan for their collaboration for environmental monitoring. The Geospatial Environmental Observation Capability (GEOC) is proposed in this study and can be used as an information basis for the reliable discovery and collaborative planning of multiple environmental sensors. A field-based GEOC (GEOCF) information representation model is built. Quintuple GEOCF feature components and two GEOCF operations are formulated based on the geospatial field conceptual framework. The proposed GEOCF markup language is used to formalize the proposed GEOCF. A prototype system called GEOCapabilityManager is developed, and a case study is conducted for flood observation in the lower reaches of the Jinsha River Basin. The applicability of the GEOCF is verified through the reliable discovery of flood monitoring sensors and planning for the collaboration of these sensors. PMID:27999247

Representing Geospatial Environment Observation Capability Information: A Case Study of Managing Flood Monitoring Sensors in the Jinsha River Basin.

PubMed

Hu, Chuli; Guan, Qingfeng; Li, Jie; Wang, Ke; Chen, Nengcheng

2016-12-16

Sensor inquirers cannot understand comprehensive or accurate observation capability information because current observation capability modeling does not consider the union of multiple sensors nor the effect of geospatial environmental features on the observation capability of sensors. These limitations result in a failure to discover credible sensors or plan for their collaboration for environmental monitoring. The Geospatial Environmental Observation Capability (GEOC) is proposed in this study and can be used as an information basis for the reliable discovery and collaborative planning of multiple environmental sensors. A field-based GEOC (GEOCF) information representation model is built. Quintuple GEOCF feature components and two GEOCF operations are formulated based on the geospatial field conceptual framework. The proposed GEOCF markup language is used to formalize the proposed GEOCF. A prototype system called GEOCapabilityManager is developed, and a case study is conducted for flood observation in the lower reaches of the Jinsha River Basin. The applicability of the GEOCF is verified through the reliable discovery of flood monitoring sensors and planning for the collaboration of these sensors.

[Risk epidemiology and child protection statistics in early childhood – a pilot study in southern Germany].

PubMed

Thurn, Leonore; Besier, Tanja; Ziegenhain, Ute; Jud, Andreas; Kindler, Heinz; Fischer, Dieter; Fegert, Jörg M; Künster, Anne Katrin

2017-07-01

In contrast to many other countries in Europe, Germany lacks sufficient empirical data on the incidence/prevalence of child maltreatment and its risk factors. This pilot study generated systematic data on the prevalence of child abuse and neglect and its risk factors in Germany. Using a newly developed questionnaire (ESM1 and ESM2) on child abuse and neglect as well as indicators for risk factors, we conducted a survey on 35 child daycare centers in a county in southern Germany, the goal being to generate reliable data. The questionnaire and the Strength and Difficulties Questionnaire (SDQ) was completed by daycare professionals for every child between 4 and under 7 years who was attending the participating daycare center (1,122 children). Child maltreatment was reported in 13.2 % of the cases, and risk factors for future child maltreatment were detected in 38.4 % cases. This study demonstrates that systematic data collection concerning child protection is feasible in child daycare centers. In the future, we recommend that local child protection networks be modified on the basis of reliable empirical data.

The long case and its modifications: a literature review.

PubMed

Ponnamperuma, Gominda G; Karunathilake, Indika M; McAleer, Sean; Davis, Margery H

2009-10-01

This review provides a summary of the published literature on the suitability of the long case and its modifications for high-stakes assessment. Databases related to medicine were searched for articles published from 2000 to 2008, using the keywords 'long case', 'clinical examinations' and 'clinical assessment'. Reference lists of review articles were hand-searched. Articles related to the objective structured clinical examination were eliminated. Research-based articles with hard data were given more emphasis in this review than those based on opinion. Eighteen articles were identified. The main disadvantage of the long case is its inability to sample the curriculum widely, resulting in low reliability. The main advantage of the long case is its ability to assess the candidate's overall (holistic) approach to the patient. Modifications to the long case attempt to: structure the format and the marking scheme; increase the number of examiners; observe the candidate's behaviour, and increase the number of cases. The long case is a traditional clinical examination format for the assessment of clinical competence and assessment at this level is important. The starting point for the majority of recent research on the long case has been an acceptance of its low reliability and modifications to the format have been proposed. Further evidence of the efficacy of these modifications is required, however, before they can be recommended for summative assessment. If further research is to be undertaken on the long case, it should focus on finding practicable ways of sampling the curriculum widely to increase reliability while maintaining the holistic approach towards the patient, which represents the attraction of the long case.

The incidence of tuberculosis in the armed forces: a good reflection of the whole population.

PubMed

Ciftci, F; Tozkoparan, E; Deniz, O; Bozkanat, E; Kibaroglu, E; Demirci, N

2004-08-01

Precise epidemiological data are essential to increase the efficiency of a tuberculosis (TB) control programme. In some countries significant numbers of TB cases go unrecorded or undetected. We aimed to investigate the incidence of TB in the Turkish Armed Forces (TAF), to obtain more reliable data on the entire population. In 2001, all soldiers with a new diagnosis of TB were enrolled in the study based on the official records of 14 military hospitals. The demographic data of the cases were evaluated. Six hundred and twenty-nine conscripts with TB were detected. Of these, 574 were aged between 20-24 years and 392 were smear-positive. The incidences of TB and smear-positive cases in TAF conscripts were calculated at respectively 76 and 47 per 100,000 population. When the age and sex distribution of the Turkish population and TB cases in Turkey were considered, the incidences of all TB and smear-positive TB in Turkey were estimated at respectively 33 and 17/100,000. These numbers are very close to those estimated by the World Health Organization. In countries where military service is compulsory and case detection rates are low, the TB incidence of the armed forces is a reliable reflection of the rate in the whole population.

The Validation of a Case-Based, Cumulative Assessment and Progressions Examination

PubMed Central

Coker, Adeola O.; Copeland, Jeffrey T.; Gottlieb, Helmut B.; Horlen, Cheryl; Smith, Helen E.; Urteaga, Elizabeth M.; Ramsinghani, Sushma; Zertuche, Alejandra; Maize, David

2016-01-01

Objective. To assess content and criterion validity, as well as reliability of an internally developed, case-based, cumulative, high-stakes third-year Annual Student Assessment and Progression Examination (P3 ASAP Exam). Methods. Content validity was assessed through the writing-reviewing process. Criterion validity was assessed by comparing student scores on the P3 ASAP Exam with the nationally validated Pharmacy Curriculum Outcomes Assessment (PCOA). Reliability was assessed with psychometric analysis comparing student performance over four years. Results. The P3 ASAP Exam showed content validity through representation of didactic courses and professional outcomes. Similar scores on the P3 ASAP Exam and PCOA with Pearson correlation coefficient established criterion validity. Consistent student performance using Kuder-Richardson coefficient (KR-20) since 2012 reflected reliability of the examination. Conclusion. Pharmacy schools can implement internally developed, high-stakes, cumulative progression examinations that are valid and reliable using a robust writing-reviewing process and psychometric analyses. PMID:26941435

Case conceptualization research in cognitive behavior therapy: A state of the science review.

PubMed

Easden, Michael H; Kazantzis, Nikolaos

2018-03-01

Prominent models of cognitive behavior therapy (CBT) assert that case conceptualization is crucial for tailoring interventions to adequately address the needs of the individual client. We aimed to review the research on case conceptualization in CBT. We conducted a systematic search of PsychINFO, MEDLINE, Psychology and Behavioral Science Collection, and CINAHL databases to February 2016. A total of 24 studies that met inclusion criteria were identified. It was notable that studies (a) focused on the assessment function of case conceptualization, (b) employed diverse methodologies, and, overall, (c) there remains a paucity of studies examining the in-session process of using case conceptualization or examining relations with outcome. Results from the existing studies suggest that experienced therapists can reliably construct some elements of case conceptualizations, but importance for the efficacy of case conceptualization in CBT has yet to be demonstrated. Research that involves direct observation of therapist competence in case conceptualization as a predictor of CBT outcomes is recommended as a focus for future hypothesis testing. © 2017 Wiley Periodicals, Inc.

Development of bus-stop time models in dense urban areas : a case study in Washington DC.

DOT National Transportation Integrated Search

2015-08-01

Bus transit reliability depends on several factors including the route of travel, traffic conditions, time of day, and conditions at : the bus stops along the route. The number of passengers alighting or boarding, fare payment method, dwell time (DT)...

Ahmad Mayyas | NREL

Science.gov Websites

University-International Center for Automotive Research (CU-ICAR) (2009-2012) Intern/Reliability Engineer selection for body-in-white." International Journal of Sustainable Manufacturing 2, no. 4 (August 2012 Structure Case Study." Accepted for publication in International Journal of Sustainable Engineering

Increasing rates of cerebral palsy across the severity spectrum in north-east England 1964-1993. The North of England Collaborative Cerebral Palsy Survey.

PubMed

Colver, A F; Gibson, M; Hey, E N; Jarvis, S N; Mackie, P C; Richmond, S

2000-07-01

To report epidemiological trends in cerebral palsy including analyses by severity. Descriptive longitudinal study in north-east England. Every child with suspected cerebral palsy was examined by a developmental paediatrician to confirm the diagnosis. Severity of impact of disability was derived from a parent completed questionnaire already developed and validated for this purpose. All children with cerebral palsy, not associated with any known postneonatal insult, born 1964-1993 to mothers resident at the time of birth in the study area. Cerebral palsy rates by year, birth weight, and severity. Severity of 30% and above defines the more reliably ascertained cases; children who died before assessment at around 6 years of age are included in the most severe group (70% and above). 584 cases of cerebral palsy were ascertained, yielding a rate that rose from 1.68 per 1000 neonatal survivors during 1964-1968 to 2.45 during 1989-1993 (rise = 0.77; 95% confidence interval 0.2-1.3). For the more reliably ascertained cases there was a twofold increase in rate from 0.98 to 1.96 (rise = 0.98; 95% confidence interval 0.5-1.4). By birth weight, increases in rates were from 29.8 to 74.2 per 1000 neonatal survivors < 1500 g and from 3.9 to 11.5 for those 1500-2499 g. Newborns < 2500 g now contribute one half of all cases of cerebral palsy and just over half of the most severe cases, whereas in the first decade of this study they contributed one third of all cases and only one sixth of the most severe (chi(2) and chi(2) for trend p < 0.001). The rate of cerebral palsy has risen in spite of falling perinatal and neonatal mortality rates, a rise that is even more pronounced when the mildest and least reliably ascertained are excluded. The effect of modern care seems to be that many babies < 2500 g who would have died in the perinatal period now survive with severe cerebral palsy. A global measure of severity should be included in registers of cerebral palsy to determine a minimum threshold for international comparisons of rates, and to monitor changes in the distribution of severity.

Reliability Analysis of the MSC System

NASA Astrophysics Data System (ADS)

Kim, Young-Soo; Lee, Do-Kyoung; Lee, Chang-Ho; Woo, Sun-Hee

2003-09-01

MSC (Multi-Spectral Camera) is the payload of KOMPSAT-2, which is being developed for earth imaging in optical and near-infrared region. The design of the MSC is completed and its reliability has been assessed from part level to the MSC system level. The reliability was analyzed in worst case and the analysis results showed that the value complies the required value of 0.9. In this paper, a calculation method of reliability for the MSC system is described, and assessment result is presented and discussed.

Is very early hearing assessment always reliable in selecting patients for cochlear implants? A case series study.

PubMed

Bovo, R; Trevisi, P; Ghiselli, S; Benatti, A; Martini, A

2015-05-01

This study concerns a case series of 23 infants with a diagnosis of severe-to-profound hearing loss at 3 months old, who significantly improved (even reaching a normal auditory threshold) within their first year of life. All infants were routinely followed up with audiological tests every 2 months after being fitted with hearing aids as necessary. A reliable consistency between the various test findings (DPOAE, ABR, behavioral responses, CAEP and ECoG) clearly emerged in most cases during the follow-up, albeit at different times after birth. The series of infants included 7 cases of severe prematurity, 6 of cerebral or complex syndromic malformations, 5 healthy infants, 2 with asymptomatic congenital CMV infection, and 1 case each of hyperbilirubinemia, hypoxia, and sepsis. All term-born infants showed a significant improvement over their initial hearing threshold by 6 months of age, while in most of those born prematurely the first signs of threshold amelioration occurred beyond 70 weeks of gestational age, and even beyond 85 weeks in one case. Cochlear implantation (CI) should only be considered after a period of auditory stimulation and follow-up with electrophysiological and behavioral tests, and an accurate analysis of their correlation. In our opinion, CI can be performed after a period of 8 months in all term-born infants with persistent severe-to-profound hearing loss without risk of diagnostic error, whereas the follow-up for severely preterm infants should extend to at least 80 weeks of gestational age. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Reliable semiclassical computations in QCD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dine, Michael; Department of Physics, Stanford University Stanford, California 94305-4060; Festuccia, Guido

We revisit the question of whether or not one can perform reliable semiclassical QCD computations at zero temperature. We study correlation functions with no perturbative contributions, and organize the problem by means of the operator product expansion, establishing a precise criterion for the validity of a semiclassical calculation. For N{sub f}>N, a systematic computation is possible; for N{sub f}

CNES reliability approach for the qualification of MEMS for space

NASA Astrophysics Data System (ADS)

Pressecq, Francis; Lafontan, Xavier; Perez, Guy; Fortea, Jean-Pierre

2001-10-01

This paper describes the reliability approach performs at CNES to evaluate MEMS for space application. After an introduction and a detailed state of the art on the space requirements and on the use of MEMS for space, different approaches for taking into account MEMS in the qualification phases are presented. CNES proposes improvement to theses approaches in term of failure mechanisms identification. Our approach is based on a design and test phase deeply linked with a technology study. This workflow is illustrated with an example: the case of a variable capacitance processed with MUMPS process is presented.

Reliability of dietary information from surrogate respondents.

PubMed

Hislop, T G; Coldman, A J; Zheng, Y Y; Ng, V T; Labo, T

1992-01-01

A self-administered food frequency questionnaire was included as part of a case-control study of breast cancer in 1980-82. In 1986-87, a second food frequency questionnaire was sent to surviving cases and husbands of deceased cases; 30 spouses (86% response rate) and 263 surviving cases (88% response rate) returned questionnaires. The dietary questions concerned consumption of specific food items by the case before diagnosis of breast cancer. Missing values were less common in the second questionnaire; there was no significant difference in missing values between surviving cases and spouses of deceased cases. Kappa statistics comparing responses in the first and second questionnaires were significantly lower for spouses of deceased cases than for surviving cases. Reported level of confidence by the husbands regarding knowledge about their wives' eating habits did not influence the kappa statistics or the frequencies of missing values. The lack of good agreement has important implications for the use of proxy interviews from husbands in retrospective dietary studies.

Reliability of windstorm predictions in the ECMWF ensemble prediction system

NASA Astrophysics Data System (ADS)

Becker, Nico; Ulbrich, Uwe

2016-04-01

Windstorms caused by extratropical cyclones are one of the most dangerous natural hazards in the European region. Therefore, reliable predictions of such storm events are needed. Case studies have shown that ensemble prediction systems (EPS) are able to provide useful information about windstorms between two and five days prior to the event. In this work, ensemble predictions with the European Centre for Medium-Range Weather Forecasts (ECMWF) EPS are evaluated in a four year period. Within the 50 ensemble members, which are initialized every 12 hours and are run for 10 days, windstorms are identified and tracked in time and space. By using a clustering approach, different predictions of the same storm are identified in the different ensemble members and compared to reanalysis data. The occurrence probability of the predicted storms is estimated by fitting a bivariate normal distribution to the storm track positions. Our results show, for example, that predicted storm clusters with occurrence probabilities of more than 50% have a matching observed storm in 80% of all cases at a lead time of two days. The predicted occurrence probabilities are reliable up to 3 days lead time. At longer lead times the occurrence probabilities are overestimated by the EPS.

Mining Available Data from the United States Environmental ...

EPA Pesticide Factsheets

Demands for quick and accurate life cycle assessments create a need for methods to rapidly generate reliable life cycle inventories (LCI). Data mining is a suitable tool for this purpose, especially given the large amount of available governmental data. These data are typically applied to LCIs on a case-by-case basis. As linked open data becomes more prevalent, it may be possible to automate LCI using data mining by establishing a reproducible approach for identifying, extracting, and processing the data. This work proposes a method for standardizing and eventually automating the discovery and use of publicly available data at the United States Environmental Protection Agency for chemical-manufacturing LCI. The method is developed using a case study of acetic acid. The data quality and gap analyses for the generated inventory found that the selected data sources can provide information with equal or better reliability and representativeness on air, water, hazardous waste, on-site energy usage, and production volumes but with key data gaps including material inputs, water usage, purchased electricity, and transportation requirements. A comparison of the generated LCI with existing data revealed that the data mining inventory is in reasonable agreement with existing data and may provide a more-comprehensive inventory of air emissions and water discharges. The case study highlighted challenges for current data management practices that must be overcome to successfu

Reliability of automatic biometric iris recognition after phacoemulsification or drug-induced pupil dilation.

PubMed

Seyeddain, Orang; Kraker, Hannes; Redlberger, Andreas; Dexl, Alois K; Grabner, Günther; Emesz, Martin

2014-01-01

To investigate the reliability of a biometric iris recognition system for personal authentication after cataract surgery or iatrogenic pupil dilation. This was a prospective, nonrandomized, single-center, cohort study for evaluating the performance of an iris recognition system 2-24 hours after phacoemulsification and intraocular lens implantation (group 1) and before and after iatrogenic pupil dilation (group 2). Of the 173 eyes that could be enrolled before cataract surgery, 164 (94.8%) were easily recognized postoperatively, whereas in 9 (5.2%) this was not possible. However, these 9 eyes could be reenrolled and afterwards recognized successfully. In group 2, of a total of 184 eyes that were enrolled in miosis, a total of 22 (11.9%) could not be recognized in mydriasis and therefore needed reenrollment. No single case of false-positive acceptance occurred in either group. The results of this trial indicate that standard cataract surgery seems not to be a limiting factor for iris recognition in the large majority of cases. Some patients (5.2% in this study) might need "reenrollment" after cataract surgery. Iris recognition was primarily successful in eyes with medically dilated pupils in nearly 9 out of 10 eyes. No single case of false-positive acceptance occurred in either group in this trial. It seems therefore that iris recognition is a valid biometric method in the majority of cases after cataract surgery or after pupil dilation.

Model-Based Assurance Case+ (MBAC+): Tutorial on Modeling Radiation Hardness Assurance Activities

NASA Technical Reports Server (NTRS)

Austin, Rebekah; Label, Ken A.; Sampson, Mike J.; Evans, John; Witulski, Art; Sierawski, Brian; Karsai, Gabor; Mahadevan, Nag; Schrimpf, Ron; Reed, Robert A.

2017-01-01

This presentation will cover why modeling is useful for radiation hardness assurance cases, and also provide information on Model-Based Assurance Case+ (MBAC+), NASAs Reliability Maintainability Template, and Fault Propagation Modeling.

How reliable are national surveillance data? Findings from an audit of Canadian methicillin-resistant Staphylococcus aureus surveillance data.

PubMed

Forrester, Leslie; Collet, Jun Chen; Mitchell, Robyn; Pelude, Linda; Henderson, Elizabeth; Vayalumkal, Joseph; Leduc, Stephanie; Ghahreman, Saeed; Weir, Christine; Gravel, Denise

2012-03-01

The Canadian Nosocomial Infection Surveillance Program (CNISP) has conducted surveillance for incident cases of methicillin-resistant Staphylococcus aureus (MRSA) in sentinel hospitals since 1995. In 2007, a reliability audit of the 2005 data was conducted. In 2005, 5,652 cases were submitted to the CNISP from 43 hospitals. A proportional sample of submitted forms (up to 25) from each site were randomly selected. Stratified random sampling was used to obtain the comparison data. The original data were compared with the reabstracted data for congruence on 7 preselected variables. Reabstracted data were received from 30 out of 43 hospitals (70%), providing 443 of the 598 case forms requested (74%). Of these, 397 (90%) had matching case identification numbers. Overall, the percentage of discordant responses was 7.0%, ranging from 3.5% for sex and up to 23.7% for less well-defined variables (eg, where MRSA was acquired). Our findings suggest that, in general, the 2005 MRSA data are reliable. However to improve reliability a data quality framework with quality assurance practices, including ongoing auditing should be integrated into the CNISP's surveillance programs. Providing training to data collectors and standard definitions with practical examples may help to improve data quality, especially for those variables that require clinical judgment. Crown Copyright © 2012. Published by Mosby, Inc. All rights reserved.

Impact of clinical history on chest radiograph interpretation.

PubMed

Test, Matthew; Shah, Samir S; Monuteaux, Michael; Ambroggio, Lilliam; Lee, Edward Y; Markowitz, Richard I; Bixby, Sarah; Diperna, Stephanie; Servaes, Sabah; Hellinger, Jeffrey C; Neuman, Mark I

2013-07-01

The inclusion of clinical information may have unrecognized influence in the interpretation of diagnostic testing. The objective of the study was to determine the impact of clinical history on chest radiograph interpretation in the diagnosis of pneumonia. Prospective case-based study. Radiologists interpreted 110 radiographs of children evaluated for suspicion of pneumonia. Clinical information was withheld during the first interpretation. After 6 months the radiographs were reviewed with clinical information. Radiologists reported on pneumonia indicators described by the World Health Organization (ie, any infiltrate, alveolar infiltrate, interstitial infiltrate, air bronchograms, hilar adenopathy, pleural effusion). Children's Hospital of Philadelphia and Boston Children's Hospital. Six board-certified radiologists. Inter- and inter-rater reliability were assessed using the kappa statistic. The addition of clinical history did not have a substantial impact on the inter-rater reliability in the identification of any infiltrate, alveolar infiltrate, interstitial infiltrate, pleural effusion, or hilar adenopathy. Inter-rater reliability in the identification of air bronchograms improved from fair (k = 0.32) to moderate (k = 0.53). Intra-rater reliability for the identification of alveolar infiltrate remained substantial to almost perfect for all 6 raters with and without clinical information. One rater had a decrease in inter-rater reliability from almost perfect (k = 1.0) to fair (k = 0.21) in the identification of interstitial infiltrate with the addition of clinical history. Alveolar infiltrate and pleural effusion are findings with high intra- and inter-rater reliability in the diagnosis of bacterial pneumonia. The addition of clinical information did not have a substantial impact on the reliability of these findings. © 2012 Society of Hospital Medicine.

Maximizing Statistical Power When Verifying Probabilistic Forecasts of Hydrometeorological Events

NASA Astrophysics Data System (ADS)

DeChant, C. M.; Moradkhani, H.

2014-12-01

Hydrometeorological events (i.e. floods, droughts, precipitation) are increasingly being forecasted probabilistically, owing to the uncertainties in the underlying causes of the phenomenon. In these forecasts, the probability of the event, over some lead time, is estimated based on some model simulations or predictive indicators. By issuing probabilistic forecasts, agencies may communicate the uncertainty in the event occurring. Assuming that the assigned probability of the event is correct, which is referred to as a reliable forecast, the end user may perform some risk management based on the potential damages resulting from the event. Alternatively, an unreliable forecast may give false impressions of the actual risk, leading to improper decision making when protecting resources from extreme events. Due to this requisite for reliable forecasts to perform effective risk management, this study takes a renewed look at reliability assessment in event forecasts. Illustrative experiments will be presented, showing deficiencies in the commonly available approaches (Brier Score, Reliability Diagram). Overall, it is shown that the conventional reliability assessment techniques do not maximize the ability to distinguish between a reliable and unreliable forecast. In this regard, a theoretical formulation of the probabilistic event forecast verification framework will be presented. From this analysis, hypothesis testing with the Poisson-Binomial distribution is the most exact model available for the verification framework, and therefore maximizes one's ability to distinguish between a reliable and unreliable forecast. Application of this verification system was also examined within a real forecasting case study, highlighting the additional statistical power provided with the use of the Poisson-Binomial distribution.

Development of a tissue engineered heart valve for pediatrics: a case study in bioengineering ethics.

PubMed

Merryman, W David

2008-03-01

The following hypothetical case study was developed for bioengineering students and is concerned with choosing between two devices used for development of a pediatric tissue engineered heart valve (TEHV). This case is intended to elicit assessment of the devices, possible future outcomes, and ramifications of the decision making. It is framed in light of two predominant ethical theories: utilitarianism and rights of persons. After the case was presented to bioengineering graduate students, they voted on which device should be released. The results revealed that these bioengineering students preferred the more reliable (and substantially more expensive) design, though this choice precludes the majority of the world from having access to this technology. This case is intended to examine and explore where the balance lies between design, cost, and adequate distribution of biomedical devices.

Data Applicability of Heritage and New Hardware for Launch Vehicle System Reliability Models

NASA Technical Reports Server (NTRS)

Al Hassan Mohammad; Novack, Steven

2015-01-01

Many launch vehicle systems are designed and developed using heritage and new hardware. In most cases, the heritage hardware undergoes modifications to fit new functional system requirements, impacting the failure rates and, ultimately, the reliability data. New hardware, which lacks historical data, is often compared to like systems when estimating failure rates. Some qualification of applicability for the data source to the current system should be made. Accurately characterizing the reliability data applicability and quality under these circumstances is crucial to developing model estimations that support confident decisions on design changes and trade studies. This presentation will demonstrate a data-source classification method that ranks reliability data according to applicability and quality criteria to a new launch vehicle. This method accounts for similarities/dissimilarities in source and applicability, as well as operating environments like vibrations, acoustic regime, and shock. This classification approach will be followed by uncertainty-importance routines to assess the need for additional data to reduce uncertainty.

Reliability of SNOMED-CT Coding by Three Physicians using Two Terminology Browsers

PubMed Central

Chiang, Michael F.; Hwang, John C.; Yu, Alexander C.; Casper, Daniel S.; Cimino, James J.; Starren, Justin

2006-01-01

SNOMED-CT has been promoted as a reference terminology for electronic health record (EHR) systems. Many important EHR functions are based on the assumption that medical concepts will be coded consistently by different users. This study is designed to measure agreement among three physicians using two SNOMED-CT terminology browsers to encode 242 concepts from five ophthalmology case presentations in a publicly-available clinical journal. Inter-coder reliability, based on exact coding match by each physician, was 44% using one browser and 53% using the other. Intra-coder reliability testing revealed that a different SNOMED-CT code was obtained up to 55% of the time when the two browsers were used by one user to encode the same concept. These results suggest that the reliability of SNOMED-CT coding is imperfect, and may be a function of browsing methodology. A combination of physician training, terminology refinement, and browser improvement may help increase the reproducibility of SNOMED-CT coding. PMID:17238317

Gonorrhea in the Unsuspected Woman

ERIC Educational Resources Information Center

Feiman, Daniel T.

1974-01-01

This study attempts to improve the control of venereal disease by screening 1,000 asymptomatic women for gonorrhea on the campus of California State University, Los Angeles. The purpose of the screening was to develop reliable statistics, to treat all cases vigorously, and to control the spread of venereal disease. (PD)

Commercial Vehicle Fleet Management And Information Systems, Technical Memorandum 1, Classification Of Fleet Operations, And Selection Of Candidate Case-Study Fleets

DOT National Transportation Integrated Search

1994-11-04

THE ECONOMIC WELL-BEING AND COMPETITIVENESS OF THE U.S. ECONOMY DEPEND HEAVILY ON RELIABLE AND EFFICIENT FREIGHT MOVEMENTS. TRUCKING ACCOUNTS FOR ABOUT 75 PERCENT ($270 BILLION) OF THE $350 BILLION SPENT ANNUALLY ON FREIGHT TRANSPORTATION. THE APPLIC...

A Study of Alternative Computer Architectures for System Reliability and Software Simplification.

DTIC Science & Technology

1981-04-22

compression. Several known applications of neighborhood processing, such as noise removal, and boundary smoothing, are shown to be special cases of...Processing [21] A small effort was undertaken to implement image array processing at a very low cost. To this end, a standard Qwip Facsimile

Performance Indicators: Information in Search of a Valid and Reliable Use.

ERIC Educational Resources Information Center

Carrigan, Sarah D.; Hackett, E. Raymond

1998-01-01

Examined the usefulness of performance indicators in campus decision making at 20 institutions with Carnegie Baccalaureate II classification using hypothesis testing and case-study approaches. Performance measures most commonly cited as measures of financial viability were of limited use for specific policy development, but were most useful within…

Optimized model tuning in medical systems.

PubMed

Kléma, Jirí; Kubalík, Jirí; Lhotská, Lenka

2005-12-01

In medical systems it is often advantageous to utilize specific problem situations (cases) in addition to or instead of a general model. Decisions are then based on relevant past cases retrieved from a case memory. The reliability of such decisions depends directly on the ability to identify cases of practical relevance to the current situation. This paper discusses issues of automated tuning in order to obtain a proper definition of mutual case similarity in a specific medical domain. The main focus is on a reasonably time-consuming optimization of the parameters that determine case retrieval and further utilization in decision making/ prediction. The two case studies - mortality prediction after cardiological intervention, and resource allocation at a spa - document that the optimization process is influenced by various characteristics of the problem domain.

[Development and testing of a preparedness and response capacity questionnaire in public health emergency for Chinese provincial and municipal governments].

PubMed

Hu, Guo-Qing; Rao, Ke-Qin; Sun, Zhen-Qiu

2008-12-01

To develop a capacity questionnaire in public health emergency for Chinese local governments. Literature reviews, conceptual modelling, stake-holder analysis, focus group, interview, and Delphi technique were employed together to develop the questionnaire. Classical test theory and case study were used to assess the reliability and validity. (1) A 2-dimension conceptual model was built. A preparedness and response capacity questionnaire in public health emergency with 10 dimensions and 204 items, was developed. (2) Reliability and validity results. Internal consistency: except for dimension 3 and 8, the Cronbach's alpha coefficient of other dimensions was higher than 0.60. The alpha coefficients of dimension 3 and dimension 8 were 0.59 and 0.39 respectively; Content validity: the questionnaire was recognized by the investigatees; Construct validity: the Spearman correlation coefficients among the 10 dimensions fluctuated around 0.50, ranging from 0.26 to 0.75 (P<0.05); Discrimination validity: comparisons of 10 dimensions among 4 provinces did not show statistical significance using One-way analysis of variance (P>0.05). Criterion-related validity: case study showed significant difference among the 10 dimensions in Beijing between February 2003 (before SARS event) and November 2005 (after SARS event). The preparedness and response capacity questionnaire in public health emergency is a reliable and valid tool, which can be used in all provinces and municipalities in China.

On optimizing the blocking step of indirect enzyme-linked immunosorbent assay for Epstein-Barr virus serology.

PubMed

Lim, Chun Shen; Krishnan, Gopala; Sam, Choon Kook; Ng, Ching Ching

2013-01-16

Because blocking agent occupies most binding surface of a solid phase, its ability to prevent nonspecific binding determines the signal-to-noise ratio (SNR) and reliability of an enzyme-linked immunosorbent assay (ELISA). We demonstrate a stepwise approach to seek a compatible blocking buffer for indirect ELISA, via a case-control study (n=176) of Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC). Regardless of case-control status, we found that synthetic polymer blocking agents, mainly Ficoll and poly(vinyl alcohol) (PVA) were able to provide homogeneous backgrounds among samples, as opposed to commonly used blocking agents, notably nonfat dry milk (NFDM). The SNRs for NPC samples that correspond to blocking using PVA were approximately 3-fold, on average, higher than those blocking using NFDM. Both intra- and inter-assay precisions of PVA-based assays were <14%. A blocking agent of choice should have tolerable sample backgrounds from both cases and controls to ensure the reliability of an immunoassay. Copyright © 2012 Elsevier B.V. All rights reserved.

Reliability and Validity Assessment of a Linear Position Transducer

PubMed Central

Garnacho-Castaño, Manuel V.; López-Lastra, Silvia; Maté-Muñoz, José L.

2015-01-01

The objectives of the study were to determine the validity and reliability of peak velocity (PV), average velocity (AV), peak power (PP) and average power (AP) measurements were made using a linear position transducer. Validity was assessed by comparing measurements simultaneously obtained using the Tendo Weightlifting Analyzer Systemi and T-Force Dynamic Measurement Systemr (Ergotech, Murcia, Spain) during two resistance exercises, bench press (BP) and full back squat (BS), performed by 71 trained male subjects. For the reliability study, a further 32 men completed both lifts using the Tendo Weightlifting Analyzer Systemz in two identical testing sessions one week apart (session 1 vs. session 2). Intraclass correlation coefficients (ICCs) indicating the validity of the Tendo Weightlifting Analyzer Systemi were high, with values ranging from 0.853 to 0.989. Systematic biases and random errors were low to moderate for almost all variables, being higher in the case of PP (bias ±157.56 W; error ±131.84 W). Proportional biases were identified for almost all variables. Test-retest reliability was strong with ICCs ranging from 0.922 to 0.988. Reliability results also showed minimal systematic biases and random errors, which were only significant for PP (bias -19.19 W; error ±67.57 W). Only PV recorded in the BS showed no significant proportional bias. The Tendo Weightlifting Analyzer Systemi emerged as a reliable system for measuring movement velocity and estimating power in resistance exercises. The low biases and random errors observed here (mainly AV, AP) make this device a useful tool for monitoring resistance training. Key points This study determined the validity and reliability of peak velocity, average velocity, peak power and average power measurements made using a linear position transducer The Tendo Weight-lifting Analyzer Systemi emerged as a reliable system for measuring movement velocity and power. PMID:25729300

A Methodology for Quantifying Certain Design Requirements During the Design Phase

NASA Technical Reports Server (NTRS)

Adams, Timothy; Rhodes, Russel

2005-01-01

A methodology for developing and balancing quantitative design requirements for safety, reliability, and maintainability has been proposed. Conceived as the basis of a more rational approach to the design of spacecraft, the methodology would also be applicable to the design of automobiles, washing machines, television receivers, or almost any other commercial product. Heretofore, it has been common practice to start by determining the requirements for reliability of elements of a spacecraft or other system to ensure a given design life for the system. Next, safety requirements are determined by assessing the total reliability of the system and adding redundant components and subsystems necessary to attain safety goals. As thus described, common practice leaves the maintainability burden to fall to chance; therefore, there is no control of recurring costs or of the responsiveness of the system. The means that have been used in assessing maintainability have been oriented toward determining the logistical sparing of components so that the components are available when needed. The process established for developing and balancing quantitative requirements for safety (S), reliability (R), and maintainability (M) derives and integrates NASA s top-level safety requirements and the controls needed to obtain program key objectives for safety and recurring cost (see figure). Being quantitative, the process conveniently uses common mathematical models. Even though the process is shown as being worked from the top down, it can also be worked from the bottom up. This process uses three math models: (1) the binomial distribution (greaterthan- or-equal-to case), (2) reliability for a series system, and (3) the Poisson distribution (less-than-or-equal-to case). The zero-fail case for the binomial distribution approximates the commonly known exponential distribution or "constant failure rate" distribution. Either model can be used. The binomial distribution was selected for modeling flexibility because it conveniently addresses both the zero-fail and failure cases. The failure case is typically used for unmanned spacecraft as with missiles.

Reliability of Health-Related Physical Fitness Tests among Colombian Children and Adolescents: The FUPRECOL Study.

PubMed

Ramírez-Vélez, Robinson; Rodrigues-Bezerra, Diogo; Correa-Bautista, Jorge Enrique; Izquierdo, Mikel; Lobelo, Felipe

2015-01-01

Substantial evidence indicates that youth physical fitness levels are an important marker of lifestyle and cardio-metabolic health profiles and predict future risk of chronic diseases. The reliability physical fitness tests have not been explored in Latino-American youth population. This study's aim was to examine the reliability of health-related physical fitness tests that were used in the Colombian health promotion "Fuprecol study". Participants were 229 Colombian youth (boys n = 124 and girls n = 105) aged 9 to 17.9 years old. Five components of health-related physical fitness were measured: 1) morphological component: height, weight, body mass index (BMI), waist circumference, triceps skinfold, subscapular skinfold, and body fat (%) via impedance; 2) musculoskeletal component: handgrip and standing long jump test; 3) motor component: speed/agility test (4x10 m shuttle run); 4) flexibility component (hamstring and lumbar extensibility, sit-and-reach test); 5) cardiorespiratory component: 20-meter shuttle-run test (SRT) to estimate maximal oxygen consumption. The tests were performed two times, 1 week apart on the same day of the week, except for the SRT which was performed only once. Intra-observer technical errors of measurement (TEMs) and inter-rater (reliability) were assessed in the morphological component. Reliability for the Musculoskeletal, motor and cardiorespiratory fitness components was examined using Bland-Altman tests. For the morphological component, TEMs were small and reliability was greater than 95% of all cases. For the musculoskeletal, motor, flexibility and cardiorespiratory components, we found adequate reliability patterns in terms of systematic errors (bias) and random error (95% limits of agreement). When the fitness assessments were performed twice, the systematic error was nearly 0 for all tests, except for the sit and reach (mean difference: -1.03% [95% CI = -4.35% to -2.28%]. The results from this study indicate that the "Fuprecol study" health-related physical fitness battery, administered by physical education teachers, was reliable for measuring health-related components of fitness in children and adolescents aged 9-17.9 years old in a school setting in Colombia.

Reliability, resilience and vulnerability criteria for the evaluation of time-dependent health risks: A hypothetical case study of wellhead protection

NASA Astrophysics Data System (ADS)

Rodak, C. M.; Silliman, S. E.; Bolster, D.

2012-12-01

A hypothetical case study of groundwater contaminant protection was carried out using time-dependent health risk calculations. The case study focuses on a hypothetical zoning project for parcels of land around a well field in northern Indiana, where the control of cancer risk relative to a mandated cancer risk threshold is of concern in the management strategy. Within our analysis, we include both uncertainty in the subsurface transport and variability in population behavior in the calculation of time-dependent health risks. From these results we introduce risk maps, a visual representation of the probability of an unacceptable health risk as a function of population behavior and the time at which exposure to the contaminant begins. We also evaluate the time-dependent risks with three criteria from water resource literature: reliability, resilience, and vulnerability (RRV). With respect to health risk from a groundwater well, the three criteria determine: the probability that a well produces safe water (reliability), the probability that a contaminated well returns to an uncontaminated state within a specified time interval (resilience), and the overall severity in terms of health impact of the contamination at a well head (vulnerability). The results demonstrate that the distributions of RRV values for each parcel of land are linked to the time-dependent concentration profile of the contaminant at the well, and the toxicological characteristics of the contaminant. The proposed time-dependent risk calculation expands on current techniques to include a continuous exposure start time, capable of reproducing the maximum risk while providing information on the severity and duration of health risks. Overall this study suggests that, especially in light of the inherent complexity of health-groundwater systems, RRV are viable criteria for relatively simple and effective evaluation of time-dependent health risk. It is argued that the RRV approach, as applied to consideration of potential health impact, allows for more informed, health-based decisions regarding zoning for wellhead protection.

Assessing local instrument reliability and validity: a field-based example from northern Uganda.

PubMed

Betancourt, Theresa S; Bass, Judith; Borisova, Ivelina; Neugebauer, Richard; Speelman, Liesbeth; Onyango, Grace; Bolton, Paul

2009-08-01

This paper presents an approach for evaluating the reliability and validity of mental health measures in non-Western field settings. We describe this approach using the example of our development of the Acholi psychosocial assessment instrument (APAI), which is designed to assess depression-like (two tam, par and kumu), anxiety-like (ma lwor) and conduct problems (kwo maraco) among war-affected adolescents in northern Uganda. To examine the criterion validity of this measure in the absence of a traditional gold standard, we derived local syndrome terms from qualitative data and used self reports of these syndromes by indigenous people as a reference point for determining caseness. Reliability was examined using standard test-retest and inter-rater methods. Each of the subscale scores for the depression-like syndromes exhibited strong internal reliability ranging from alpha = 0.84-0.87. Internal reliability was good for anxiety (0.70), conduct problems (0.83), and the pro-social attitudes and behaviors (0.70) subscales. Combined inter-rater reliability and test-retest reliability were good for most subscales except for the conduct problem scale and prosocial scales. The pattern of significant mean differences in the corresponding APAI problem scale score between self-reported cases vs. noncases on local syndrome terms was confirmed in the data for all of the three depression-like syndromes, but not for the anxiety-like syndrome ma lwor or the conduct problem kwo maraco.

Assessment of the impact of the scanner-related factors on brain morphometry analysis with Brainvisa

PubMed Central

2011-01-01

Background Brain morphometry is extensively used in cross-sectional studies. However, the difference in the estimated values of the morphometric measures between patients and healthy subjects may be small and hence overshadowed by the scanner-related variability, especially with multicentre and longitudinal studies. It is important therefore to investigate the variability and reliability of morphometric measurements between different scanners and different sessions of the same scanner. Methods We assessed the variability and reliability for the grey matter, white matter, cerebrospinal fluid and cerebral hemisphere volumes as well as the global sulcal index, sulcal surface and mean geodesic depth using Brainvisa. We used datasets obtained across multiple MR scanners at 1.5 T and 3 T from the same groups of 13 and 11 healthy volunteers, respectively. For each morphometric measure, we conducted ANOVA analysis and verified whether the estimated values were significantly different across different scanners or different sessions of the same scanner. The between-centre and between-visit reliabilities were estimated from their contribution to the total variance, using a random-effects ANOVA model. To estimate the main processes responsible for low reliability, the results of brain segmentation were compared to those obtained using FAST within FSL. Results In a considerable number of cases, the main effects of both centre and visit factors were found to be significant. Moreover, both between-centre and between-visit reliabilities ranged from poor to excellent for most morphometric measures. A comparison between segmentation using Brainvisa and FAST revealed that FAST improved the reliabilities for most cases, suggesting that morphometry could benefit from improving the bias correction. However, the results were still significantly different across different scanners or different visits. Conclusions Our results confirm that for morphometry analysis with the current version of Brainvisa using data from multicentre or longitudinal studies, the scanner-related variability must be taken into account and where possible should be corrected for. We also suggest providing some flexibility to Brainvisa for a step-by-step analysis of the robustness of this package in terms of reproducibility of the results by allowing the bias corrected images to be imported from other packages and bias correction step be skipped, for example. PMID:22189342

Strategic Word Attack: Acquired Contextual Strategies in Young Readers.

ERIC Educational Resources Information Center

Matz, Karl A.

A study demonstrated that young children who have difficulty with phonics can be taught to read through other methods, that phonics is only one of the many useful strategies that a child can employ, and that many contextual strategies are easier to learn and more reliable than phonics. A case study was conducted during an intervention with a young…

Dropping out of Vocational Education in the State of Kuwait: A Case Study of Industrial Arts Students

ERIC Educational Resources Information Center

Alqahtani, Abdulmuhsen Ayedh; Almutairi, Yousef B.

2013-01-01

The purpose of the current study is to examine, in retrospect, trainees' perceptions of the reasons some of their peers dropped out of the vocational education at the Industrial Institute-Shuwaikh (IIS), Kuwait. Using the descriptive-analytical method, a reliable questionnaire was developed to achieve this purpose. Results show that: (a) the…

Cephalometric and three-dimensional assessment of the posterior airway space and imaging software reliability analysis before and after orthognathic surgery.

PubMed

Burkhard, John Patrik Matthias; Dietrich, Ariella Denise; Jacobsen, Christine; Roos, Malgorzota; Lübbers, Heinz-Theo; Obwegeser, Joachim Anton

2014-10-01

This study aimed to compare the reliability of three different imaging software programs for measuring the PAS and concurrently to investigate the morphological changes in oropharyngeal structures in mandibular prognathic patients before and after orthognathic surgery by using 2D and 3D analyzing technique. The study consists of 11 randomly chosen patients (8 females and 3 males) who underwent maxillomandibular treatment for correction of Class III anteroposterior mandibular prognathism at the University Hospital in Zurich. A set of standardized LCR and CBCT-scans were obtained from each subject preoperatively (T0), 3 months after surgery (T1) and 3 months to 2 years postoperatively (T2). Morphological changes in the posterior airway space (PAS) were evaluated longitudinally by two different observers with three different imaging software programs (OsiriX(®) 64-bit, Switzerland; Mimics(®), Belgium; BrainLab(®), Germany) and manually by analyzing cephalometric X-rays. A significant increase in the upper airway dimensions before and after surgery occurred in all measured cases. All other cephalometric distances showed no statistically significant alterations. Measuring the volume of the PAS showed no significant changes in all cases. All three software programs showed similar outputs in both cephalometric analysis and 3D measuring technique. A 3D design of the posterior airway seems to be far more reliable and precise phrasing of a statement of postoperative gradients than conventional radiography and is additionally higher compared to the corresponding manual method. In case of Class III mandibular prognathism treatment with bilateral split osteotomy of the mandible and simultaneous maxillary advancement, the negative effects of PAS volume decrease may be reduced and might prevent a developing OSAS. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

A new SPECT/CT reconstruction algorithm: reliability and accuracy in clinical routine for non-oncologic bone diseases.

PubMed

Delcroix, Olivier; Robin, Philippe; Gouillou, Maelenn; Le Duc-Pennec, Alexandra; Alavi, Zarrin; Le Roux, Pierre-Yves; Abgral, Ronan; Salaun, Pierre-Yves; Bourhis, David; Querellou, Solène

2018-02-12

xSPECT Bone® (xB) is a new reconstruction algorithm developed by Siemens® in bone hybrid imaging (SPECT/CT). A CT-based tissue segmentation is incorporated into SPECT reconstruction to provide SPECT images with bone anatomy appearance. The objectives of this study were to assess xB/CT reconstruction diagnostic reliability and accuracy in comparison with Flash 3D® (F3D)/CT in clinical routine. Two hundred thirteen consecutive patients referred to the Brest Nuclear Medicine Department for non-oncological bone diseases were evaluated retrospectively. Two hundred seven SPECT/CT were included. All SPECT/CT were independently interpreted by two nuclear medicine physicians (a junior and a senior expert) with xB/CT then with F3D/CT three months later. Inter-observer agreement (IOA) and diagnostic confidence were determined using McNemar test, and unweighted Kappa coefficient. The study objectives were then re-assessed for validation through > 18 months of clinical and paraclinical follow-up. No statistically significant differences between IOA xB and IOA F3D were found (p = 0.532). Agreement for xB after categorical classification of the diagnoses was high (κ xB = 0.89 [95% CI 0.84 -0.93]) but without statistically significant difference F3D (κ F3D = 0.90 [95% CI 0.86 - 0.94]). Thirty-one (14.9%) inter-reconstruction diagnostic discrepancies were observed of which 21 (10.1%) were classified as major. The follow-up confirmed the diagnosis of F3D in 10 cases, xB in 6 cases and was non-contributory in 5 cases. xB reconstruction algorithm was found reliable, providing high interobserver agreement and similar diagnostic confidence to F3D reconstruction in clinical routine.

Toronto Bariatric Interprofessional Psychosocial Assessment Suitability Scale: Evaluating A New Clinical Assessment Tool for Bariatric Surgery Candidates.

PubMed

Thiara, Gurneet; Yanofksy, Richard; Abdul-Kader, Sayed; Santiago, Vincent A; Cassin, Stephanie; Okrainec, Allan; Jackson, Timothy; Hawa, Raed; Sockalingam, Sanjeev

2016-01-01

Patients who are referred for possible bariatric surgery (BS) intervention undergo a series of assessments conducted by an interdisciplinary health care team to determine suitability for surgery. Herein, we report the initial validation and reliability studies of the Bariatric Interprofessional Psychosocial Assessment Suitability Scale (BIPASS) and its relationship to interdisciplinary psychosocial assessment practices for BS. This study was conducted at the Toronto Western Hospital, a Level 1A BS center of excellence accredited by the American College of Surgeons. Phase I: a total of 4 blinded raters applied the BIPASS to 31 randomly selected BS cases referred to our program to establish interrater reliability. Phase II: in all, 3 raters with clinical experience in bariatric psychosocial care applied the BIPASS to 54 randomly selected BS cases. In total, 46 of 54 (85.1%) patients were women. The median age of all patient cases was 49 years (range: 21-74). Raters׳ BIPASS scores ranged from 4-52 (median = 19.24, standard deviation =10.38). BIPASS scores were highly predictive of the BS psychosocial outcome (area under curve = 0.915; 95% CI: 0.844-0.985; p < 0.001). A BIPASS score of ≥16 was chosen as the cutoff score for further clinical assessment before proceeding with surgical evaluation based on a receiver operating characteristic curve analysis (sensitivity = 0.839; specificity = 0.783). The instrument has very good interrater reliability (Pearson correlation coefficient = 0.847) even among novice raters. The findings show that the BIPASS is a comprehensive screening tool in the psychosocial assessment of BS candidates, which standardizes the evaluation process and systematically identify at-risk patients for negative outcomes after BS. Copyright © 2016 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.

Optimizing study design for interobserver reliability: IUGA-ICS classification of complications of prostheses and graft insertion.

PubMed

Haylen, Bernard T; Lee, Joseph; Maher, Chris; Deprest, Jan; Freeman, Robert

2014-06-01

Results of interobserver reliability studies for the International Urogynecological Association-International Continence Society (IUGA-ICS) Complication Classification coding can be greatly influenced by study design factors such as participant instruction, motivation, and test-question clarity. We attempted to optimize these factors. After a 15-min instructional lecture with eight clinical case examples (including images) and with classification/coding charts available, those clinicians attending an IUGA Surgical Complications workshop were presented with eight similar-style test cases over 10 min and asked to code them using the Category, Time and Site classification. Answers were compared to predetermined correct codes obtained by five instigators of the IUGA-ICS prostheses and grafts complications classification. Prelecture and postquiz participant confidence levels using a five-step Likert scale were assessed. Complete sets of answers to the questions (24 codings) were provided by 34 respondents, only three of whom reported prior use of the charts. Average score [n (%)] out of eight, as well as median score (range) for each coding category were: (i) Category: 7.3 (91 %); 7 (4-8); (ii) Time: 7.8 (98 %); 7 (6-8); (iii) Site: 7.2 (90 %); 7 (5-8). Overall, the equivalent calculations (out of 24) were 22.3 (93 %) and 22 (18-24). Mean prelecture confidence was 1.37 (out of 5), rising to 3.85 postquiz. Urogynecologists had the highest correlation with correct coding, followed closely by fellows and general gynecologists. Optimizing training and study design can lead to excellent results for interobserver reliability of the IUGA-ICS Complication Classification coding, with increased participant confidence in complication-coding ability.

Use of Comparative Case Study Methodology for US Public Health Policy Analysis: A Review.

PubMed

Dinour, Lauren M; Kwan, Amy; Freudenberg, Nicholas

There is growing recognition that policies influence population health, highlighting the need for evidence to inform future policy development and reform. This review describes how comparative case study methodology has been applied to public health policy research and discusses the methodology's potential to contribute to this evidence. English-language, peer-reviewed articles published between 1995 and 2012 were sought from 4 databases. Articles were included if they described comparative case studies addressing US public health policy. Two researchers independently assessed the 20 articles meeting review criteria. Case-related characteristics and research design tactics utilized to minimize threats to reliability and validity, such as the use of multiple sources of evidence and a case study protocol, were extracted from each article. Although comparative case study methodology has been used to analyze a range of public health policies at all stages and levels, articles reported an average use of only 3.65 (out of 10) research design tactics. By expanding the use of accepted research design tactics, public health policy researchers can contribute to expanding the evidence needed to advance health-promoting policies.

Optimal clustering of MGs based on droop controller for improving reliability using a hybrid of harmony search and genetic algorithms.

PubMed

Abedini, Mohammad; Moradi, Mohammad H; Hosseinian, S M

2016-03-01

This paper proposes a novel method to address reliability and technical problems of microgrids (MGs) based on designing a number of self-adequate autonomous sub-MGs via adopting MGs clustering thinking. In doing so, a multi-objective optimization problem is developed where power losses reduction, voltage profile improvement and reliability enhancement are considered as the objective functions. To solve the optimization problem a hybrid algorithm, named HS-GA, is provided, based on genetic and harmony search algorithms, and a load flow method is given to model different types of DGs as droop controller. The performance of the proposed method is evaluated in two case studies. The results provide support for the performance of the proposed method. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Creation and Initial Validation of the International Dysphagia Diet Standardisation Initiative Functional Diet Scale

PubMed Central

Steele, Catriona M.; Namasivayam-MacDonald, Ashwini M.; Guida, Brittany T.; Cichero, Julie A.; Duivestein, Janice; MRSc; Hanson, Ben; Lam, Peter; Riquelme, Luis F.

2018-01-01

Objective To assess consensual validity, interrater reliability, and criterion validity of the International Dysphagia Diet Standardisation Initiative Functional Diet Scale, a new functional outcome scale intended to capture the severity of oropharyngeal dysphagia, as represented by the degree of diet texture restriction recommended for the patient. Design Participants assigned International Dysphagia Diet Standardisation Initiative Functional Diet Scale scores to 16 clinical cases. Consensual validity was measured against reference scores determined by an author reference panel. Interrater reliability was measured overall and across quartile subsets of the dataset. Criterion validity was evaluated versus Functional Oral Intake Scale (FOIS) scores assigned by survey respondents to the same case scenarios. Feedback was requested regarding ease and likelihood of use. Setting Web-based survey. Participants Respondents (NZ170) from 29 countries. Interventions Not applicable. Main Outcome Measures Consensual validity (percent agreement and Kendall t), criterion validity (Spearman rank correlation), and interrater reliability (Kendall concordance and intraclass coefficients). Results The International Dysphagia Diet Standardisation Initiative Functional Diet Scale showed strong consensual validity, criterion validity, and interrater reliability. Scenarios involving liquid-only diets, transition from nonoral feeding, or trial diet advances in therapy showed the poorest consensus, indicating a need for clear instructions on how to score these situations. The International Dysphagia Diet Standardisation Initiative Functional Diet Scale showed greater sensitivity than the FOIS to specific changes in diet. Most (>70%) respondents indicated enthusiasm for implementing the International Dysphagia Diet Standardisation Initiative Functional Diet Scale. Conclusions This initial validation study suggests that the International Dysphagia Diet Standardisation Initiative Functional Diet Scale has strong consensual and criterion validity and can be used reliably by clinicians to capture diet texture restriction and progression in people with dysphagia. PMID:29428348

Creation and Initial Validation of the International Dysphagia Diet Standardisation Initiative Functional Diet Scale.

PubMed

Steele, Catriona M; Namasivayam-MacDonald, Ashwini M; Guida, Brittany T; Cichero, Julie A; Duivestein, Janice; Hanson, Ben; Lam, Peter; Riquelme, Luis F

2018-05-01

To assess consensual validity, interrater reliability, and criterion validity of the International Dysphagia Diet Standardisation Initiative Functional Diet Scale, a new functional outcome scale intended to capture the severity of oropharyngeal dysphagia, as represented by the degree of diet texture restriction recommended for the patient. Participants assigned International Dysphagia Diet Standardisation Initiative Functional Diet Scale scores to 16 clinical cases. Consensual validity was measured against reference scores determined by an author reference panel. Interrater reliability was measured overall and across quartile subsets of the dataset. Criterion validity was evaluated versus Functional Oral Intake Scale (FOIS) scores assigned by survey respondents to the same case scenarios. Feedback was requested regarding ease and likelihood of use. Web-based survey. Respondents (N=170) from 29 countries. Not applicable. Consensual validity (percent agreement and Kendall τ), criterion validity (Spearman rank correlation), and interrater reliability (Kendall concordance and intraclass coefficients). The International Dysphagia Diet Standardisation Initiative Functional Diet Scale showed strong consensual validity, criterion validity, and interrater reliability. Scenarios involving liquid-only diets, transition from nonoral feeding, or trial diet advances in therapy showed the poorest consensus, indicating a need for clear instructions on how to score these situations. The International Dysphagia Diet Standardisation Initiative Functional Diet Scale showed greater sensitivity than the FOIS to specific changes in diet. Most (>70%) respondents indicated enthusiasm for implementing the International Dysphagia Diet Standardisation Initiative Functional Diet Scale. This initial validation study suggests that the International Dysphagia Diet Standardisation Initiative Functional Diet Scale has strong consensual and criterion validity and can be used reliably by clinicians to capture diet texture restriction and progression in people with dysphagia. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

What makes an accurate and reliable subject-specific finite element model? A case study of an elephant femur

PubMed Central

Panagiotopoulou, O.; Wilshin, S. D.; Rayfield, E. J.; Shefelbine, S. J.; Hutchinson, J. R.

2012-01-01

Finite element modelling is well entrenched in comparative vertebrate biomechanics as a tool to assess the mechanical design of skeletal structures and to better comprehend the complex interaction of their form–function relationships. But what makes a reliable subject-specific finite element model? To approach this question, we here present a set of convergence and sensitivity analyses and a validation study as an example, for finite element analysis (FEA) in general, of ways to ensure a reliable model. We detail how choices of element size, type and material properties in FEA influence the results of simulations. We also present an empirical model for estimating heterogeneous material properties throughout an elephant femur (but of broad applicability to FEA). We then use an ex vivo experimental validation test of a cadaveric femur to check our FEA results and find that the heterogeneous model matches the experimental results extremely well, and far better than the homogeneous model. We emphasize how considering heterogeneous material properties in FEA may be critical, so this should become standard practice in comparative FEA studies along with convergence analyses, consideration of element size, type and experimental validation. These steps may be required to obtain accurate models and derive reliable conclusions from them. PMID:21752810

Assessment of Semi-Structured Clinical Interview for Mobile Phone Addiction Disorder.

PubMed

Alavi, Seyyed Salman; Mohammadi, Mohammad Reza; Jannatifard, Fereshteh; Mohammadi Kalhori, Soroush; Sepahbodi, Ghazal; BabaReisi, Mohammad; Sajedi, Sahar; Farshchi, Mojtaba; KhodaKarami, Rasul; Hatami Kasvaee, Vahid

2016-04-01

The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) classified mobile phone addiction disorder under "impulse control disorder not elsewhere classified". This study surveyed the diagnostic criteria of DSM-IV-TR for the diagnosis of mobile phone addiction in correspondence with Iranian society and culture. Two hundred fifty students of Tehran universities were entered into this descriptive-analytical and cross-sectional study. Quota sampling method was used. At first, semi- structured clinical interview (based on DSM-IV-TR) was performed for all the cases, and another specialist reevaluated the interviews. Data were analyzed using content validity, inter-scorer reliability (Kappa coefficient) and test-retest via SPSS18 software. The content validity of the semi- structured clinical interview matched the DSM-IV-TR criteria for behavioral addiction. Moreover, their content was appropriate, and two items, including "SMS pathological use" and "High monthly cost of using the mobile phone" were added to promote its validity. Internal reliability (Kappa) and test-retest reliability were 0.55 and r = 0.4 (p<0. 01) respectively. The results of this study revealed that semi- structured diagnostic criteria of DSM-IV-TR are valid and reliable for diagnosing mobile phone addiction, and this instrument is an effective tool to diagnose this disorder.

Reliability prediction of ontology-based service compositions using Petri net and time series models.

PubMed

Li, Jia; Xia, Yunni; Luo, Xin

2014-01-01

OWL-S, one of the most important Semantic Web service ontologies proposed to date, provides a core ontological framework and guidelines for describing the properties and capabilities of their web services in an unambiguous, computer interpretable form. Predicting the reliability of composite service processes specified in OWL-S allows service users to decide whether the process meets the quantitative quality requirement. In this study, we consider the runtime quality of services to be fluctuating and introduce a dynamic framework to predict the runtime reliability of services specified in OWL-S, employing the Non-Markovian stochastic Petri net (NMSPN) and the time series model. The framework includes the following steps: obtaining the historical response times series of individual service components; fitting these series with a autoregressive-moving-average-model (ARMA for short) and predicting the future firing rates of service components; mapping the OWL-S process into a NMSPN model; employing the predicted firing rates as the model input of NMSPN and calculating the normal completion probability as the reliability estimate. In the case study, a comparison between the static model and our approach based on experimental data is presented and it is shown that our approach achieves higher prediction accuracy.

A Report on Simulation-Driven Reliability and Failure Analysis of Large-Scale Storage Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wan, Lipeng; Wang, Feiyi; Oral, H. Sarp

High-performance computing (HPC) storage systems provide data availability and reliability using various hardware and software fault tolerance techniques. Usually, reliability and availability are calculated at the subsystem or component level using limited metrics such as, mean time to failure (MTTF) or mean time to data loss (MTTDL). This often means settling on simple and disconnected failure models (such as exponential failure rate) to achieve tractable and close-formed solutions. However, such models have been shown to be insufficient in assessing end-to-end storage system reliability and availability. We propose a generic simulation framework aimed at analyzing the reliability and availability of storagemore » systems at scale, and investigating what-if scenarios. The framework is designed for an end-to-end storage system, accommodating the various components and subsystems, their interconnections, failure patterns and propagation, and performs dependency analysis to capture a wide-range of failure cases. We evaluate the framework against a large-scale storage system that is in production and analyze its failure projections toward and beyond the end of lifecycle. We also examine the potential operational impact by studying how different types of components affect the overall system reliability and availability, and present the preliminary results« less

The development of an instrument to match individuals with disabilities and service animals.

PubMed

Zapf, S A; Rough, R B

There has been an increase in the use of service animals assisting persons with disabilities in the past decade. However many of the service dog agencies do not utilize an assessment that is designed to match the person to the animal in the rehabilitation and psycho-social domains. The purpose of this study was to develop the Service Animal Adaptive Intervention Assessment (SAAIA) and to measure the content validity, inter-rater reliability and clinical utility of the assessment. Two subject groups were used. Subject group one had 43 subjects who measured the content validity and clinical utility of the SAAIA Survey. Subject group two had 12 subjects who measured the inter-rater reliability by completing the SAAIA using information obtained through a video-taped client case scenario. Content validity results indicated a good to high percentage of agreement and a fair percentage of agreement for clinical utility. Inter-rater reliability results indicate good to high agreement on six of the eight variables of the SAAIA. However, the Kappa score indicates low inter-rater reliability. Results indicate the SAAIA has good content validity and inter-rater reliability and fair clinical utility based on percent agreement. However, further research is needed on the reliability of the SAAIA.

The Study of the Relationship between Probabilistic Design and Axiomatic Design Methodology. Volume 3

NASA Technical Reports Server (NTRS)

Onwubiko, Chin-Yere; Onyebueke, Landon

1996-01-01

Structural failure is rarely a "sudden death" type of event, such sudden failures may occur only under abnormal loadings like bomb or gas explosions and very strong earthquakes. In most cases, structures fail due to damage accumulated under normal loadings such as wind loads, dead and live loads. The consequence of cumulative damage will affect the reliability of surviving components and finally causes collapse of the system. The cumulative damage effects on system reliability under time-invariant loadings are of practical interest in structural design and therefore will be investigated in this study. The scope of this study is, however, restricted to the consideration of damage accumulation as the increase in the number of failed components due to the violation of their strength limits.

The validity and reliability of the sixth-year internal medical examination administered at the King Abdulaziz University Medical College.

PubMed

Fallatah, Hind I; Tekian, Ara; Park, Yoon Soo; Al Shawa, Lana

2015-02-01

Exams are essential components of medical students' knowledge and skill assessment during their clinical years of study. The paper provides a retrospective analysis of validity evidence for the internal medicine component of the written and clinical exams administered in 2012 and 2013 at King Abdulaziz University's Faculty of Medicine. Students' scores for the clinical and written exams were obtained. Four faculty members (two senior members and two junior members) were asked to rate the exam questions, including MCQs and OSCEs, for evidence of content validity using a rating scale of 1-5 for each item. Cronbach's alpha was used to measure the internal consistency reliability. Correlations were used to examine the associations between different forms of assessment and groups of students. A total of 824 students completed the internal medicine course and took the exam. The numbers of rated questions were 320 and 46 for the MCQ and OSCE, respectively. Significant correlations were found between the MCQ section, the OSCE section, and the continuous assessment marks, which include 20 long-case presentations during the course; participation in daily rounds, clinical sessions and tutorials; the performance of simple procedures, such as IV cannulation and ABG extraction; and the student log book. Although the OSCE exam was reliable for the two groups that had taken the final clinical OSCE, the clinical long- and short-case exams were not reliable across the two groups that had taken the oral clinical exams. The correlation analysis showed a significant linear association between the raters with respect to evidence of content validity for both the MCQ and OSCE, r = .219 P < .001 and r = .678 P < .001, respectively, and r = .241 P < .001 and r = .368 P = .023 for the internal structure validity, respectively. Reliability measured using Cronbach's alpha was greater for assessments administered in 2013. The pattern of relationships between the MCQ and OSCE scores provides evidence of the validity of these measures for use in the evaluation of knowledge and clinical skills in internal medicine. The OSCE exam is more reliable than the short- and long-case clinical exams and requires less effort on the part of examiners and patients.

Challenges Regarding IP Core Functional Reliability

NASA Technical Reports Server (NTRS)

Berg, Melanie D.; LaBel, Kenneth A.

2017-01-01

For many years, intellectual property (IP) cores have been incorporated into field programmable gate array (FPGA) and application specific integrated circuit (ASIC) design flows. However, the usage of large complex IP cores were limited within products that required a high level of reliability. This is no longer the case. IP core insertion has become mainstream including their use in highly reliable products. Due to limited visibility and control, challenges exist when using IP cores and subsequently compromise product reliability. We discuss challenges and suggest potential solutions to critical application IP insertion.

Plastic Encapsulated Microcircuits (PEMs) Reliability Guide

NASA Technical Reports Server (NTRS)

Sandor, M.

2000-01-01

It is reported by some users and has been demonstrated by others via testing and qualification that the quality and reliability of plastic-encapsulated microcircuits (PEMs) manufactured today are excellent in commercial applications and closely equivalent, and in some cases superior to their hemetic counterparts.

3D Biometrics for Hindfoot Alignment Using Weightbearing CT.

PubMed

Lintz, François; Welck, Matthew; Bernasconi, Alessio; Thornton, James; Cullen, Nicholas P; Singh, Dishan; Goldberg, Andy

2017-06-01

Hindfoot alignment on 2D radiographs can present anatomical and operator-related bias. In this study, software designed for weightbearing computed tomography (WBCT) was used to calculate a new 3D biometric tool: the Foot and Ankle Offset (FAO). We described the distribution of FAO in a series of data sets from clinically normal, varus, and valgus cases, hypothesizing that FAO values would be significantly different in the 3 groups. In this retrospective cohort study, 135 data sets (57 normal, 38 varus, 40 valgus) from WBCT (PedCAT; CurveBeam LLC, Warrington, PA) were obtained from a specialized foot and ankle unit. 3D coordinates of specific anatomical landmarks (weightbearing points of the calcaneus, of the first and fifth metatarsal heads and the highest and centermost point on the talar dome) were collected. These data were processed with the TALAS system (CurveBeam), which resulted in an FAO value for each case. Intraobserver and interobserver reliability were also assessed. In normal cases, the mean value for FAO was 2.3% ± 2.9%, whereas in varus and valgus cases, the mean was -11.6% ± 6.9% and 11.4% ± 5.7%, respectively, with a statistically significant difference among groups ( P < .001). The distribution of the normal population was Gaussian. The inter- and intraobserver reliability were 0.99 +/- 0.00 and 0.97 +/-0.02 Conclusions: This pilot study suggests that the FAO is an efficient tool for measuring hindfoot alignment using WBCT. Previously published research in this field has looked at WBCT by adapting 2D biometrics. The present study introduces the concept of 3D biometrics and describes an efficient, semiautomatic tool for measuring hindfoot alignment. Level III, retrospective comparative study.

The role of production and teamwork practices in construction safety: a cognitive model and an empirical case study.

PubMed

Mitropoulos, Panagiotis Takis; Cupido, Gerardo

2009-01-01

In construction, the challenge for researchers and practitioners is to develop work systems (production processes and teams) that can achieve high productivity and high safety at the same time. However, construction accident causation models ignore the role of work practices and teamwork. This study investigates the mechanisms by which production and teamwork practices affect the likelihood of accidents. The paper synthesizes a new model for construction safety based on the cognitive perspective (Fuller's Task-Demand-Capability Interface model, 2005) and then presents an exploratory case study. The case study investigates and compares the work practices of two residential framing crews: a 'High Reliability Crew' (HRC)--that is, a crew with exceptional productivity and safety over several years, and an average performing crew from the same company. The model explains how the production and teamwork practices generate the work situations that workers face (the task demands) and affect the workers ability to cope (capabilities). The case study indicates that the work practices of the HRC directly influence the task demands and match them with the applied capabilities. These practices were guided by the 'principle' of avoiding errors and rework and included work planning and preparation, work distribution, managing the production pressures, and quality and behavior monitoring. The Task Demand-Capability model links construction research to a cognitive model of accident causation and provides a new way to conceptualize safety as an emergent property of the production practices and teamwork processes. The empirical evidence indicates that the crews' work practices and team processes strongly affect the task demands, the applied capabilities, and the match between demands and capabilities. The proposed model and the exploratory case study will guide further discovery of work practices and teamwork processes that can increase both productivity and safety in construction operations. Such understanding will enable training of construction foremen and crews in these practices to systematically develop high reliability crews.

Clinical peri-implant sounding accuracy in the presence of chronic inflammation of peri-implant tissues. Clinical observation study.

PubMed

Romeo, E; Lops, D; Storelli, S; Ghisolfi, M

2009-03-01

The aim of this study was to assess if the probing pocket depth is a reliable clinical parameter in the evaluation of the depth of the peri-implant sulci. In case of chronic inflamed peri-implant tissues, this evaluation is useful for understanding the level of bone resorption. The study enrolled 22 patients. All of them were diagnosed for a peri-implantitis and were scheduled for a resective surgery with implantoplasty. During the surgery, a full thickness flap was raised and resective surgery was performed as well as an implantoplasty procedure. Peri-implant probing values before the surgery (PAL) were recorded, as were values of bone resorption after flap elevation (DIB), at all four sites around each implant (88 sites). The mean value of PAL calculated for all 88 sites was 5.67 mm (+/-1.46); the correspondent value of DIB was 6.37 mm (+/-1.81). In 52 sites out of 88 (59.1%) the values of PAL and DIB were exactly the same (maximum difference 0.5 mm). In only 10 cases (11.3%) the difference between PAL and DIB was >2 mm. The mean values for PAL and DIB were not statistically different. Authors have concluded that in case of chronic inflammation of peri-implant tissues, the probe reaches the bone pick, allowing the clinician to have reliable information on the actual bone resorption.

Comprehensive Deployment Method for Technical Characteristics Base on Multi-failure Modes Correlation Analysis

NASA Astrophysics Data System (ADS)

Zheng, W.; Gao, J. M.; Wang, R. X.; Chen, K.; Jiang, Y.

2017-12-01

This paper put forward a new method of technical characteristics deployment based on Reliability Function Deployment (RFD) by analysing the advantages and shortages of related research works on mechanical reliability design. The matrix decomposition structure of RFD was used to describe the correlative relation between failure mechanisms, soft failures and hard failures. By considering the correlation of multiple failure modes, the reliability loss of one failure mode to the whole part was defined, and a calculation and analysis model for reliability loss was presented. According to the reliability loss, the reliability index value of the whole part was allocated to each failure mode. On the basis of the deployment of reliability index value, the inverse reliability method was employed to acquire the values of technology characteristics. The feasibility and validity of proposed method were illustrated by a development case of machining centre’s transmission system.

The accuracy of officially reported suicide statistics for purposes of epidemiological research.

PubMed Central

Sainsbury, P; Jenkins, J S

1982-01-01

Suicide is underreported for a number of reasons and the reliability of the official rates is subject to error from variation in defining and reporting cases--the kind of inaccuracies encountered when ascertaining cases in studies of mortality from any cause. Nevertheless, the evidence from studies designed to see whether these sources of error invalidate the differences reported between cultural and social groups indicate that they are randomised, at least to an extent that allows epidemiologists to compare rates between countries and districts within them, between demographic groups, and over time. PMID:7069354

Validation of the 'United Registries for Clinical Assessment and Research' [UR-CARE], a European Online Registry for Clinical Care and Research in Inflammatory Bowel Disease.

PubMed

Burisch, Johan; Gisbert, Javier P; Siegmund, Britta; Bettenworth, Dominik; Thomsen, Sandra Bohn; Cleynen, Isabelle; Cremer, Anneline; Ding, Nik John Sheng; Furfaro, Federica; Galanopoulos, Michail; Grunert, Philip Christian; Hanzel, Jurij; Ivanovski, Tamara Knezevic; Krustins, Eduards; Noor, Nurulamin; O'Morain, Neil; Rodríguez-Lago, Iago; Scharl, Michael; Tua, Julia; Uzzan, Mathieu; Ali Yassin, Nuha; Baert, Filip; Langholz, Ebbe

2018-04-27

The 'United Registries for Clinical Assessment and Research' [UR-CARE] database is an initiative of the European Crohn's and Colitis Organisation [ECCO] to facilitate daily patient care and research studies in inflammatory bowel disease [IBD]. Herein, we sought to validate the database by using fictional case histories of patients with IBD that were to be entered by observers of varying experience in IBD. Nineteen observers entered five patient case histories into the database. After 6 weeks, all observers entered the same case histories again. For each case history, 20 key variables were selected to calculate the accuracy for each observer. We assumed that the database was such that ≥ 90% of the entered data would be correct. The overall proportion of correctly entered data was calculated using a beta-binomial regression model to account for inter-observer variation and compared to the expected level of validity. Re-test reliability was assessed using McNemar's test. For all case histories, the overall proportion of correctly entered items and their confidence intervals included the target of 90% (Case 1: 92% [88-94%]; Case 2: 87% [83-91%]; Case 3: 93% [90-95%]; Case 4: 97% [94-99%]; Case 5: 91% [87-93%]). These numbers did not differ significantly from those found 6 weeks later [NcNemar's test p > 0.05]. The UR-CARE database appears to be feasible, valid and reliable as a tool and easy to use regardless of prior user experience and level of clinical IBD experience. UR-CARE has the potential to enhance future European collaborations regarding clinical research in IBD.

Reliable Facility Location Problem with Facility Protection

PubMed Central

Tang, Luohao; Zhu, Cheng; Lin, Zaili; Shi, Jianmai; Zhang, Weiming

2016-01-01

This paper studies a reliable facility location problem with facility protection that aims to hedge against random facility disruptions by both strategically protecting some facilities and using backup facilities for the demands. An Integer Programming model is proposed for this problem, in which the failure probabilities of facilities are site-specific. A solution approach combining Lagrangian Relaxation and local search is proposed and is demonstrated to be both effective and efficient based on computational experiments on random numerical examples with 49, 88, 150 and 263 nodes in the network. A real case study for a 100-city network in Hunan province, China, is presented, based on which the properties of the model are discussed and some managerial insights are analyzed. PMID:27583542

The protonation of N2O reexamined - A case study on the reliability of various electron correlation methods for minima and transition states

NASA Technical Reports Server (NTRS)

Martin, J. M. L.; Lee, Timothy J.

1993-01-01

The protonation of N2O and the intramolecular proton transfer in N2OH(+) are studied using various basis sets and a variety of methods, including second-order many-body perturbation theory (MP2), singles and doubles coupled cluster (CCSD), the augmented coupled cluster (CCSD/T/), and complete active space self-consistent field (CASSCF) methods. For geometries, MP2 leads to serious errors even for HNNO(+); for the transition state, only CCSD/T/ produces a reliable geometry due to serious nondynamical correlation effects. The proton affinity at 298.15 K is estimated at 137.6 kcal/mol, in close agreement with recent experimental determinations of 137.3 +/- 1 kcal/mol.

The Advantages of Normalizing Electromyography to Ballistic Rather than Isometric or Isokinetic Tasks.

PubMed

Suydam, Stephen M; Manal, Kurt; Buchanan, Thomas S

2017-07-01

Isometric tasks have been a standard for electromyography (EMG) normalization stemming from anatomic and physiologic stability observed during contraction. Ballistic dynamic tasks have the benefit of eliciting maximum EMG signals for normalization, despite having the potential for greater signal variability. It is the purpose of this study to compare maximum voluntary isometric contraction (MVIC) to nonisometric tasks with increasing degrees of extrinsic variability, ie, joint range of motion, velocity, rate of contraction, etc., to determine if the ballistic tasks, which elicit larger peak EMG signals, are more reliable than the constrained MVIC. Fifteen subjects performed MVIC, isokinetic, maximum countermovement jump, and sprint tasks while EMG was collected from 9 muscles in the quadriceps, hamstrings, and lower leg. The results revealed the unconstrained ballistic tasks were more reliable compared to the constrained MVIC and isokinetic tasks for all triceps surae muscles. The EMG from sprinting was more reliable than the constrained cases for both the hamstrings and vasti. The most reliable EMG signals occurred when the body was permitted its natural, unconstrained motion. These results suggest that EMG is best normalized using ballistic tasks to provide the greatest within-subject reliability, which beneficially yield maximum EMG values.

The role and reliability of the Psychopathy Checklist-Revised in U.S. sexually violent predator evaluations: a case law survey.

PubMed

DeMatteo, David; Edens, John F; Galloway, Meghann; Cox, Jennifer; Smith, Shannon Toney; Formon, Dana

2014-06-01

The civil commitment of offenders as sexually violent predators (SVPs) is a highly contentious area of U.S. mental health law. The Psychopathy Checklist-Revised (PCL-R) is frequently used in mental health evaluations in these cases to aid legal decision making. Although generally perceived to be a useful assessment tool in applied settings, recent research has raised questions about the reliability of PCL-R scores in SVP cases. In this report, we review the use of the PCL-R in SVP trials identified as part of a larger project investigating its role in U.S. case law. After presenting data on how the PCL-R is used in SVP cases, we examine the reliability of scores reported in these cases. We located 214 cases involving the PCL-R, 88 of which included an actual score and 29 of which included multiple scores. In the 29 cases with multiple scores, the intraclass correlation coefficient for a single evaluator for the PCL-R scores was only .58, and only 41.4% of the difference scores were within 1 standard error of measurement unit. The average score reported by prosecution experts was significantly higher than the average score reported by defense-retained experts, and prosecution experts reported PCL-R scores of 30 or above in nearly 50% of the cases, compared with less than 10% of the cases for defense witnesses (κ = .29). In conjunction with other recently published findings demonstrating the unreliability of PCL-R scores in applied settings, our results raise questions as to whether this instrument should be admitted into SVP proceedings.

Quality of laboratory studies assessing effects of Bt-proteins on non-target organisms: minimal criteria for acceptability.

PubMed

De Schrijver, Adinda; Devos, Yann; De Clercq, Patrick; Gathmann, Achim; Romeis, Jörg

2016-08-01

The potential risks that genetically modified plants may pose to non-target organisms and the ecosystem services they contribute to are assessed as part of pre-market risk assessments. This paper reviews the early tier studies testing the hypothesis whether exposure to plant-produced Cry34/35Ab1 proteins as a result of cultivation of maize 59122 is harmful to valued non-target organisms, in particular Arthropoda and Annelida. The available studies were assessed for their scientific quality by considering a set of criteria determining their relevance and reliability. As a case-study, this exercise revealed that when not all quality criteria are met, weighing the robustness of the study and its relevance for risk assessment is not obvious. Applying a worst-case expected environmental concentration of bioactive toxins equivalent to that present in the transgenic crop, confirming exposure of the test species to the test substance, and the use of a negative control were identified as minimum criteria to be met to guarantee sufficiently reliable data. This exercise stresses the importance of conducting studies meeting certain quality standards as this minimises the probability of erroneous or inconclusive results and increases confidence in the results and adds certainty to the conclusions drawn.

Parvovirus infection: an immunohistochemical study using fetal and placental tissue.

PubMed

Li, Jing Jing; Henwood, Tony; Van Hal, Sebastian; Charlton, Amanda

2015-01-01

Parvovirus B19 infection causes 5% to 15% of cases of nonimmune hydrops fetalis. The aim of our study was to evaluate the use of immunohistochemistry in diagnosing parvovirus infection in fetal and placental tissue during routine fetal and perinatal autopsies. Histology slides of 20 cases of confirmed parvovirus infection were reviewed, and immunohistochemistry was applied to selected blocks of fetal and placental tissue. Immunohistochemistry was positive in all 20 cases, and histologic viral inclusions were seen in 19 cases. Immunohistochemical staining was closely correlated with histology and was more sensitive than histology in detecting virally infected cells, especially in autolyzed tissue. All cases also had confirmatory evidence of parvovirus infection by polymerase chain reaction of fetal liver and positive maternal serology, where it was available. We conclude that parvovirus immunohistochemistry is a reliable method for diagnosing parvovirus infection, especially in autolyzed tissue where histologic assessment may be suboptimal.

Business Cases for Microgrids: Modeling Interactions of Technology Choice, Reliability, Cost, and Benefit

NASA Astrophysics Data System (ADS)

Hanna, Ryan

Distributed energy resources (DERs), and increasingly microgrids, are becoming an integral part of modern distribution systems. Interest in microgrids--which are insular and autonomous power networks embedded within the bulk grid--stems largely from the vast array of flexibilities and benefits they can offer stakeholders. Managed well, they can improve grid reliability and resiliency, increase end-use energy efficiency by coupling electric and thermal loads, reduce transmission losses by generating power locally, and may reduce system-wide emissions, among many others. Whether these public benefits are realized, however, depends on whether private firms see a "business case", or private value, in investing. To this end, firms need models that evaluate costs, benefits, risks, and assumptions that underlie decisions to invest. The objectives of this dissertation are to assess the business case for microgrids that provide what industry analysts forecast as two primary drivers of market growth--that of providing energy services (similar to an electric utility) as well as reliability service to customers within. Prototypical first adopters are modeled--using an existing model to analyze energy services and a new model that couples that analysis with one of reliability--to explore interactions between technology choice, reliability, costs, and benefits. The new model has a bi-level hierarchy; it uses heuristic optimization to select and size DERs and analytical optimization to schedule them. It further embeds Monte Carlo simulation to evaluate reliability as well as regression models for customer damage functions to monetize reliability. It provides least-cost microgrid configurations for utility customers who seek to reduce interruption and operating costs. Lastly, the model is used to explore the impact of such adoption on system-wide greenhouse gas emissions in California. Results indicate that there are, at present, co-benefits for emissions reductions when customers adopt and operate microgrids for private benefit, though future analysis is needed as the bulk grid continues to transition toward a less carbon intensive system.

Forensic Child Sexual Abuse Evaluations: Assessing Subjectivity and Bias in Professional Judgements

ERIC Educational Resources Information Center

Everson, Mark D.; Sandoval, Jose Miguel

2011-01-01

Objectives: Evaluators examining the same evidence often arrive at substantially different conclusions in forensic assessments of child sexual abuse (CSA). This study attempts to identify and quantify subjective factors that contribute to such disagreements so that interventions can be devised to improve the reliability of case decisions. Methods:…

29 CFR 4.51 - Prevailing in the locality determinations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... applied in a given case will be determined after a careful analysis of the overall survey, separate... where, after analysis, it is determined that the median is not a reliable indicator. Examples where the mean may be used include situations where: (1) The number of workers studied for the job classification...

Quantifying Children's Aggregate (Dietary and Residential) Exposure and Dose to Permethin: Application and Evaluation of EPA's Probabilistic SHED-Multimedia Model

EPA Science Inventory

Reliable, evaluated human exposure and dose models are important for understanding the health risks from chemicals. A case study focusing on permethrin was conducted because of this insecticide’s widespread use and potential health effects. SHEDS-Multimedia was applied to estimat...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cadwallader, Lee C.; Zhao, Haihua

In this study, selected accident case histories are described that illustrate the potential modes of injury from gas jets, pressure-driven missiles, and asphyxiants. Gas combustion hazards are also briefly mentioned. Using high-pressure helium and nitrogen, estimates of safe exclusion distances are calculated for differing pressures, temperatures, and breach sizes. Some sources for gas system reliability values are also cited.

78 FR 40020 - Fenbuconazole; Pesticide Tolerances

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-03

... average PCT is less than one. In those cases, 1% is used as the average PCT and 2.5% is used as the... one of the following methods: Federal eRulemaking Portal: http://www.regulations.gov . Follow the... validity, completeness, and reliability as well as the relationship of the results of the studies to human...

Incorporating intelligent transportation systems into planning analysis : summary of key findings from a 2020 case study -- improving travel time reliability with ITS

DOT National Transportation Integrated Search

2002-05-01

ITS is typically considered an operational detail to be worked out after infrastructure planning is complete. This approach ignores the potential for the introduction of ITS to change the decisions made during infrastructure planning, or even the ove...

Alternative Fuels Data Center: Minnesota Transportation Data for

Science.gov Websites

Energy Laboratory Case Studies Video thumbnail for Minnesota School District Finds Cost Savings, Cold Reliability with Propane Buses Jan. 26, 2016 Video thumbnail for Minneapolis Makes EV-Charging History Record Minnesota Videos on YouTube Video thumbnail for GE Showcases Innovation in Alternative Fuel Vehicles GE

Competing risk models in reliability systems, an exponential distribution model with Bayesian analysis approach

NASA Astrophysics Data System (ADS)

Iskandar, I.

2018-03-01

The exponential distribution is the most widely used reliability analysis. This distribution is very suitable for representing the lengths of life of many cases and is available in a simple statistical form. The characteristic of this distribution is a constant hazard rate. The exponential distribution is the lower rank of the Weibull distributions. In this paper our effort is to introduce the basic notions that constitute an exponential competing risks model in reliability analysis using Bayesian analysis approach and presenting their analytic methods. The cases are limited to the models with independent causes of failure. A non-informative prior distribution is used in our analysis. This model describes the likelihood function and follows with the description of the posterior function and the estimations of the point, interval, hazard function, and reliability. The net probability of failure if only one specific risk is present, crude probability of failure due to a specific risk in the presence of other causes, and partial crude probabilities are also included.

Feasibility and reliability of remote assessment of PALS psychomotor skills via interactive videoconferencing.

PubMed

Weeks, Douglas L; Molsberry, Dianne M

2009-03-01

This study determined inter-rater agreement between skill assessments provided by on-site PALS evaluators with ratings from evaluators at a remote site viewing the same skill performance over a videoconferencing network. Judgments about feasibility of remote evaluation were also obtained from the evaluators and PALS course participants. Two remote and two on-site instructors independently rated performance of 27 course participants who performed cardiac and shock/respiratory emergency core cases. Inter-rater reliability was assessed with the intraclass correlation coefficient (ICC). Feasibility was assessed with surveys of evaluators and course participants. Core cases were under the direction of the remote evaluators. The ICC for overall agreement on pass/fail decisions was 0.997 for the cardiac cases and 0.998 for the shock/respiratory cases. Perfect agreement was reached on 52 of 54 pass/fail decisions. Across all evaluators, all core cases, and all participants, 2584 ratings of individual skill criteria were provided, of which 21 (0.8%) were ratings in which a single evaluator disagreed with the other three evaluators. No trends emerged for location of the disagreeing evaluator. Survey responses indicated that remote evaluation was acceptable and feasible to course participants and to the evaluators. Videoconferencing technology was shown to provide adequate spatial and temporal resolution for PALS evaluators at-a-distance from course participants to agree with ratings of on-site evaluators.

Inter-rater agreement in evaluation of disability: systematic review of reproducibility studies

PubMed Central

Barth, Jürgen; de Boer, Wout E L; Busse, Jason W; Hoving, Jan L; Kedzia, Sarah; Couban, Rachel; Fischer, Katrin; von Allmen, David Y; Spanjer, Jerry

2017-01-01

Objectives To explore agreement among healthcare professionals assessing eligibility for work disability benefits. Design Systematic review and narrative synthesis of reproducibility studies. Data sources Medline, Embase, and PsycINFO searched up to 16 March 2016, without language restrictions, and review of bibliographies of included studies. Eligibility criteria Observational studies investigating reproducibility among healthcare professionals performing disability evaluations using a global rating of working capacity and reporting inter-rater reliability by a statistical measure or descriptively. Studies could be conducted in insurance settings, where decisions on ability to work include normative judgments based on legal considerations, or in research settings, where decisions on ability to work disregard normative considerations.Teams of paired reviewers identified eligible studies, appraised their methodological quality and generalisability, and abstracted results with pretested forms. As heterogeneity of research designs and findings impeded a quantitative analysis, a descriptive synthesis stratified by setting (insurance or research) was performed. Results From 4562 references, 101 full text articles were reviewed. Of these, 16 studies conducted in an insurance setting and seven in a research setting, performed in 12 countries, met the inclusion criteria. Studies in the insurance setting were conducted with medical experts assessing claimants who were actual disability claimants or played by actors, hypothetical cases, or short written scenarios. Conditions were mental (n=6, 38%), musculoskeletal (n=4, 25%), or mixed (n=6, 38%). Applicability of findings from studies conducted in an insurance setting to real life evaluations ranged from generalisable (n=7, 44%) and probably generalisable (n=3, 19%) to probably not generalisable (n=6, 37%). Median inter-rater reliability among experts was 0.45 (range intraclass correlation coefficient 0.86 to κ−0.10). Inter-rater reliability was poor in six studies (37%) and excellent in only two (13%). This contrasts with studies conducted in the research setting, where the median inter-rater reliability was 0.76 (range 0.91-0.53), and 71% (5/7) studies achieved excellent inter-rater reliability. Reliability between assessing professionals was higher when the evaluation was guided by a standardised instrument (23 studies, P=0.006). No such association was detected for subjective or chronic health conditions or the studies’ generalisability to real world evaluation of disability (P=0.46, 0.45, and 0.65, respectively). Conclusions Despite their common use and far reaching consequences for workers claiming disabling injury or illness, research on the reliability of medical evaluations of disability for work is limited and indicates high variation in judgments among assessing professionals. Standardising the evaluation process could improve reliability. Development and testing of instruments and structured approaches to improve reliability in evaluation of disability are urgently needed. PMID:28122727

Within-trial contrast: when you see it and when you don't.

PubMed

Zentall, Thomas R

2008-02-01

Within-trial contrast occurs when a discriminative stimulus that is preceded by a relatively aversive event is preferred over another that is preceded by a less aversive event. Recent failures to replicate (Arantes & Grace, 2008; Vasconcelos, Urcuioli, & Lionello-DeNolf, 2007) may allow us to identify factors that may be responsible. In the case of Vasconcelos et al., it is likely that insufficient training was provided (often 35-65 sessions are required). In the case of Arantes and Grace (Experiment 2), these pigeons had been involved in prior experiments involving lean schedules of reinforcement, and we find that prior experience its occurrence. with lean (relatively aversive) schedules appears to reduce the presumed aversiveness of the many-peck requirement, thus obviating the contrast effect. Finally, in the case of Vasconcelos and Urcuioli (2008), although the contrast effect with a simultaneous discrimination was not reliable, it was not reliably smaller than with a successive discrimination that did show a reliable effect, and the contrast effect was also similar in magnitude to a reliable effect reported by Kacelnik and Marsh (2002). Thus, although there have been several failures to replicate the original effects reported by Clement, Feltus, Kaiser and Zentall (2000), insufficient training, prior history with lean schedules of reinforcement, and low statistical power may have been responsible for those failures.

Prevalence and Reliability of Phonological, Surface, and Mixed Profiles in Dyslexia: A Review of Studies Conducted in Languages Varying in Orthographic Depth

ERIC Educational Resources Information Center

Sprenger-Charolles, Liliane; Siegel, Linda S.; Jimenez, Juan E.; Ziegler, Johannes C.

2011-01-01

The influence of orthographic transparency on the prevalence of dyslexia subtypes was examined in a review of multiple-case studies conducted in languages differing in orthographic depth (English, French, and Spanish). Cross-language differences are found in the proportion of dissociated profiles as a function of the dependent variables (speed or…

Deliberate Self-Harm within an International Community Sample of Young People: Comparative Findings from the Child & Adolescent Self-Harm in Europe (CASE) Study

ERIC Educational Resources Information Center

Madge, Nicola; Hewitt, Anthea; Hawton, Keith; de Wilde, Erik Jan; Corcoran, Paul; Fekete, Sandor; van Heeringen, Kees; De Leo, Diego; Ystgaard, Mette

2008-01-01

Background: Deliberate self-harm among young people is an important focus of policy and practice internationally. Nonetheless, there is little reliable comparative international information on its extent or characteristics. We have conducted a seven-country comparative community study of deliberate self-harm among young people. Method: Over 30,000…

Curriculum Evaluation in Online Education: The Case of Teacher Candidates Preparing Online for Public Personnel Selection Examination

ERIC Educational Resources Information Center

Karacaoglu, Ömer Cem

2018-01-01

The aim of the present study is to evaluate the efficiency of an online curriculum based on the views of lecturers and students enrolled in the program. The study is mainly based on survey method. In order to collect qualitative data, interviews forms developed by the researcher were used. The reliability and validity of the interview forms were…

Medicine is not science: guessing the future, predicting the past.

PubMed

Miller, Clifford

2014-12-01

Irregularity limits human ability to know, understand and predict. A better understanding of irregularity may improve the reliability of knowledge. Irregularity and its consequences for knowledge are considered. Reliable predictive empirical knowledge of the physical world has always been obtained by observation of regularities, without needing science or theory. Prediction from observational knowledge can remain reliable despite some theories based on it proving false. A naïve theory of irregularity is outlined. Reducing irregularity and/or increasing regularity can increase the reliability of knowledge. Beyond long experience and specialization, improvements include implementing supporting knowledge systems of libraries of appropriately classified prior cases and clinical histories and education about expertise, intuition and professional judgement. A consequence of irregularity and complexity is that classical reductionist science cannot provide reliable predictions of the behaviour of complex systems found in nature, including of the human body. Expertise, expert judgement and their exercise appear overarching. Diagnosis involves predicting the past will recur in the current patient applying expertise and intuition from knowledge and experience of previous cases and probabilistic medical theory. Treatment decisions are an educated guess about the future (prognosis). Benefits of the improvements suggested here are likely in fields where paucity of feedback for practitioners limits development of reliable expert diagnostic intuition. Further analysis, definition and classification of irregularity is appropriate. Observing and recording irregularities are initial steps in developing irregularity theory to improve the reliability and extent of knowledge, albeit some forms of irregularity present inherent difficulties. © 2014 John Wiley & Sons, Ltd.

Squash preparation: A reliable diagnostic tool in the intraoperative diagnosis of central nervous system tumors

PubMed Central

Mitra, Sumit; Kumar, Mohan; Sharma, Vivek; Mukhopadhyay, Debasis

2010-01-01

Background: Intraoperative cytology is an important diagnostic modality improving on the accuracy of the frozen sections. It has shown to play an important role especially in the intraoperative diagnosis of central nervous system tumors. Aim: To study the diagnostic accuracy of squash preparation and frozen section (FS) in the intraoperative diagnosis of central nervous system (CNS) tumors. Materials and Methods: This prospective study of 114 patients with CNS tumors was conducted over a period of 18 months (September 2004 to February 2006). The cytological preparations were stained by the quick Papanicolaou method. The squash interpretation and FS diagnosis were later compared with the paraffin section diagnosis. Results: Of the 114 patients, cytological diagnosis was offered in 96 cases. Eighteen nonneoplastic or noncontributory cases were excluded. Using hematoxylin and eosin-stained histopathology sections as the gold standard, the diagnostic accuracy of cytology was 88.5% (85/96) and the accuracy on FS diagnosis was 90.6% (87/96). Among these cases, gliomas formed the largest category of tumors (55.2%). The cytological accuracy in this group was 84.9% (45/53) and the comparative FS figure was 86.8% (46/53). In cases where the smear and the FS diagnosis did not match, the latter opinion was offered. Conclusions: Squash preparation is a reliable, rapid and easy method and can be used as a complement to FS in the intraoperative diagnosis of CNS tumors. PMID:21187881

Diagnosing Developmental Dyscalculia on the Basis of Reliable Single Case FMRI Methods: Promises and Limitations

PubMed Central

Dinkel, Philipp Johannes; Willmes, Klaus; Krinzinger, Helga; Konrad, Kerstin; Koten Jr, Jan Willem

2013-01-01

FMRI-studies are mostly based on a group study approach, either analyzing one group or comparing multiple groups, or on approaches that correlate brain activation with clinically relevant criteria or behavioral measures. In this study we investigate the potential of fMRI-techniques focusing on individual differences in brain activation within a test-retest reliability context. We employ a single-case analysis approach, which contrasts dyscalculic children with a control group of typically developing children. In a second step, a support-vector machine analysis and cluster analysis techniques served to investigate similarities in multivariate brain activation patterns. Children were confronted with a non-symbolic number comparison and a non-symbolic exact calculation task during fMRI acquisition. Conventional second level group comparison analysis only showed small differences around the angular gyrus bilaterally and the left parieto-occipital sulcus. Analyses based on single-case statistical procedures revealed that developmental dyscalculia is characterized by individual differences predominantly in visual processing areas. Dyscalculic children seemed to compensate for relative under-activation in the primary visual cortex through an upregulation in higher visual areas. However, overlap in deviant activation was low for the dyscalculic children, indicating that developmental dyscalculia is a disorder characterized by heterogeneous brain activation differences. Using support vector machine analysis and cluster analysis, we tried to group dyscalculic and typically developing children according to brain activation. Fronto-parietal systems seem to qualify for a distinction between the two groups. However, this was only effective when reliable brain activations of both tasks were employed simultaneously. Results suggest that deficits in number representation in the visual-parietal cortex get compensated for through finger related aspects of number representation in fronto-parietal cortex. We conclude that dyscalculic children show large individual differences in brain activation patterns. Nonetheless, the majority of dyscalculic children can be differentiated from controls employing brain activation patterns when appropriate methods are used. PMID:24349547

Diagnosing developmental dyscalculia on the basis of reliable single case FMRI methods: promises and limitations.

PubMed

Dinkel, Philipp Johannes; Willmes, Klaus; Krinzinger, Helga; Konrad, Kerstin; Koten, Jan Willem

2013-01-01

FMRI-studies are mostly based on a group study approach, either analyzing one group or comparing multiple groups, or on approaches that correlate brain activation with clinically relevant criteria or behavioral measures. In this study we investigate the potential of fMRI-techniques focusing on individual differences in brain activation within a test-retest reliability context. We employ a single-case analysis approach, which contrasts dyscalculic children with a control group of typically developing children. In a second step, a support-vector machine analysis and cluster analysis techniques served to investigate similarities in multivariate brain activation patterns. Children were confronted with a non-symbolic number comparison and a non-symbolic exact calculation task during fMRI acquisition. Conventional second level group comparison analysis only showed small differences around the angular gyrus bilaterally and the left parieto-occipital sulcus. Analyses based on single-case statistical procedures revealed that developmental dyscalculia is characterized by individual differences predominantly in visual processing areas. Dyscalculic children seemed to compensate for relative under-activation in the primary visual cortex through an upregulation in higher visual areas. However, overlap in deviant activation was low for the dyscalculic children, indicating that developmental dyscalculia is a disorder characterized by heterogeneous brain activation differences. Using support vector machine analysis and cluster analysis, we tried to group dyscalculic and typically developing children according to brain activation. Fronto-parietal systems seem to qualify for a distinction between the two groups. However, this was only effective when reliable brain activations of both tasks were employed simultaneously. Results suggest that deficits in number representation in the visual-parietal cortex get compensated for through finger related aspects of number representation in fronto-parietal cortex. We conclude that dyscalculic children show large individual differences in brain activation patterns. Nonetheless, the majority of dyscalculic children can be differentiated from controls employing brain activation patterns when appropriate methods are used.

Forecasting malaria incidence based on monthly case reports and environmental factors in Karuzi, Burundi, 1997–2003

PubMed Central

Gomez-Elipe, Alberto; Otero, Angel; van Herp, Michel; Aguirre-Jaime, Armando

2007-01-01

Background The objective of this work was to develop a model to predict malaria incidence in an area of unstable transmission by studying the association between environmental variables and disease dynamics. Methods The study was carried out in Karuzi, a province in the Burundi highlands, using time series of monthly notifications of malaria cases from local health facilities, data from rain and temperature records, and the normalized difference vegetation index (NDVI). Using autoregressive integrated moving average (ARIMA) methodology, a model showing the relation between monthly notifications of malaria cases and the environmental variables was developed. Results The best forecasting model (R2adj = 82%, p < 0.0001 and 93% forecasting accuracy in the range ± 4 cases per 100 inhabitants) included the NDVI, mean maximum temperature, rainfall and number of malaria cases in the preceding month. Conclusion This model is a simple and useful tool for producing reasonably reliable forecasts of the malaria incidence rate in the study area. PMID:17892540

Reliability and Probabilistic Risk Assessment - How They Play Together

NASA Technical Reports Server (NTRS)

Safie, Fayssal; Stutts, Richard; Huang, Zhaofeng

2015-01-01

Since the Space Shuttle Challenger accident in 1986, NASA has extensively used probabilistic analysis methods to assess, understand, and communicate the risk of space launch vehicles. Probabilistic Risk Assessment (PRA), used in the nuclear industry, is one of the probabilistic analysis methods NASA utilizes to assess Loss of Mission (LOM) and Loss of Crew (LOC) risk for launch vehicles. PRA is a system scenario based risk assessment that uses a combination of fault trees, event trees, event sequence diagrams, and probability distributions to analyze the risk of a system, a process, or an activity. It is a process designed to answer three basic questions: 1) what can go wrong that would lead to loss or degraded performance (i.e., scenarios involving undesired consequences of interest), 2) how likely is it (probabilities), and 3) what is the severity of the degradation (consequences). Since the Challenger accident, PRA has been used in supporting decisions regarding safety upgrades for launch vehicles. Another area that was given a lot of emphasis at NASA after the Challenger accident is reliability engineering. Reliability engineering has been a critical design function at NASA since the early Apollo days. However, after the Challenger accident, quantitative reliability analysis and reliability predictions were given more scrutiny because of their importance in understanding failure mechanism and quantifying the probability of failure, which are key elements in resolving technical issues, performing design trades, and implementing design improvements. Although PRA and reliability are both probabilistic in nature and, in some cases, use the same tools, they are two different activities. Specifically, reliability engineering is a broad design discipline that deals with loss of function and helps understand failure mechanism and improve component and system design. PRA is a system scenario based risk assessment process intended to assess the risk scenarios that could lead to a major/top undesirable system event, and to identify those scenarios that are high-risk drivers. PRA output is critical to support risk informed decisions concerning system design. This paper describes the PRA process and the reliability engineering discipline in detail. It discusses their differences and similarities and how they work together as complementary analyses to support the design and risk assessment processes. Lessons learned, applications, and case studies in both areas are also discussed in the paper to demonstrate and explain these differences and similarities.

Uncertainty-Based Multi-Objective Optimization of Groundwater Remediation Design

NASA Astrophysics Data System (ADS)

Singh, A.; Minsker, B.

2003-12-01

Management of groundwater contamination is a cost-intensive undertaking filled with conflicting objectives and substantial uncertainty. A critical source of this uncertainty in groundwater remediation design problems comes from the hydraulic conductivity values for the aquifer, upon which the prediction of flow and transport of contaminants are dependent. For a remediation solution to be reliable in practice it is important that it is robust over the potential error in the model predictions. This work focuses on incorporating such uncertainty within a multi-objective optimization framework, to get reliable as well as Pareto optimal solutions. Previous research has shown that small amounts of sampling within a single-objective genetic algorithm can produce highly reliable solutions. However with multiple objectives the noise can interfere with the basic operations of a multi-objective solver, such as determining non-domination of individuals, diversity preservation, and elitism. This work proposes several approaches to improve the performance of noisy multi-objective solvers. These include a simple averaging approach, taking samples across the population (which we call extended averaging), and a stochastic optimization approach. All the approaches are tested on standard multi-objective benchmark problems and a hypothetical groundwater remediation case-study; the best-performing approach is then tested on a field-scale case at Umatilla Army Depot.

Comparison of disease activity measures for anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis.

PubMed

Merkel, P A; Cuthbertson, D D; Hellmich, B; Hoffman, G S; Jayne, D R W; Kallenberg, C G M; Krischer, J P; Luqmani, R; Mahr, A D; Matteson, E L; Specks, U; Stone, J H

2009-01-01

Currently, several different instruments are used to measure disease activity and extent in clinical trials of anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis, leading to division among investigative groups and difficulty comparing study results. An exercise comparing six different vasculitis instruments was performed. A total of 10 experienced vasculitis investigators from 5 countries scored 20 cases in the literature of Wegener granulomatosis or microscopic polyangiitis using 6 disease assessment tools: the Birmingham Vasculitis Activity Score (BVAS), The BVAS for Wegener granulomatosis (BVAS/WG), BVAS 2003, a Physician Global Assessment (PGA), the Disease Extent Index (DEI) and the Five Factor Score (FFS). Five cases were rescored by all raters. Reliability of the measures was extremely high (intraclass correlations for the six measures all = 0.98). Within each instrument, there were no significant differences or outliers among the scores from the 10 investigators. Test/retest reliability was high for each measure: range = 0.77 to 0.95. The scores of the five acute activity measures correlated extremely well with one another. Currently available tools for measuring disease extent and activity in ANCA-associated vasculitis are highly correlated and reliable. These results provide investigators with confidence to compare different clinical trial data and helps form common ground as international research groups develop new, improved and universally accepted vasculitis disease assessment instruments.

Reliability analysis of multicellular system architectures for low-cost satellites

NASA Astrophysics Data System (ADS)

Erlank, A. O.; Bridges, C. P.

2018-06-01

Multicellular system architectures are proposed as a solution to the problem of low reliability currently seen amongst small, low cost satellites. In a multicellular architecture, a set of independent k-out-of-n systems mimic the cells of a biological organism. In order to be beneficial, a multicellular architecture must provide more reliability per unit of overhead than traditional forms of redundancy. The overheads include power consumption, volume and mass. This paper describes the derivation of an analytical model for predicting a multicellular system's lifetime. The performance of such architectures is compared against that of several common forms of redundancy and proven to be beneficial under certain circumstances. In addition, the problem of peripheral interfaces and cross-strapping is investigated using a purpose-developed, multicellular simulation environment. Finally, two case studies are presented based on a prototype cell implementation, which demonstrate the feasibility of the proposed architecture.

National audit of continence care: laying the foundation.

PubMed

Mian, Sarah; Wagg, Adrian; Irwin, Penny; Lowe, Derek; Potter, Jonathan; Pearson, Michael

2005-12-01

National audit provides a basis for establishing performance against national standards, benchmarking against other service providers and improving standards of care. For effective audit, clinical indicators are required that are valid, feasible to apply and reliable. This study describes the methods used to develop clinical indicators of continence care in preparation for a national audit. To describe the methods used to develop and test clinical indicators of continence care with regard to validity, feasibility and reliability. A multidisciplinary working group developed clinical indicators that measured the structure, process and outcome of care as well as case-mix variables. Literature searching, consensus workshops and a Delphi process were used to develop the indicators. The indicators were tested in 15 secondary care sites, 15 primary care sites and 15 long-term care settings. The process of development produced indicators that received a high degree of consensus within the Delphi process. Testing of the indicators demonstrated an internal reliability of 0.7 and an external reliability of 0.6. Data collection required significant investment in terms of staff time and training. The method used produced indicators that achieved a high degree of acceptance from health care professionals. The reliability of data collection was high for this audit and was similar to the level seen in other successful national audits. Data collection for the indicators was feasible to collect, however, issues of time and staffing were identified as limitations to such data collection. The study has described a systematic method for developing clinical indicators for national audit. The indicators proved robust and reliable in primary and secondary care as well as long-term care settings.

Modeling reliability measurement of interface on information system: Towards the forensic of rules

NASA Astrophysics Data System (ADS)

Nasution, M. K. M.; Sitompul, Darwin; Harahap, Marwan

2018-02-01

Today almost all machines depend on the software. As a software and hardware system depends also on the rules that are the procedures for its use. If the procedure or program can be reliably characterized by involving the concept of graph, logic, and probability, then regulatory strength can also be measured accordingly. Therefore, this paper initiates an enumeration model to measure the reliability of interfaces based on the case of information systems supported by the rules of use by the relevant agencies. An enumeration model is obtained based on software reliability calculation.

Optimum allocation of redundancy among subsystems connected in series. Ph.D. Thesis - Case Western Reserve Univ., Sep. 1970

NASA Technical Reports Server (NTRS)

Bien, D. D.

1973-01-01

This analysis considers the optimum allocation of redundancy in a system of serially connected subsystems in which each subsystem is of the k-out-of-n type. Redundancy is optimally allocated when: (1) reliability is maximized for given costs; or (2) costs are minimized for given reliability. Several techniques are presented for achieving optimum allocation and their relative merits are discussed. Approximate solutions in closed form were attainable only for the special case of series-parallel systems and the efficacy of these approximations is discussed.

Fatigue Lifespan of Engine Box Influenced by Fan Blade Out

NASA Astrophysics Data System (ADS)

Qiu, Ju; Shi, Jingwei; Su, Huaizhong; Zhang, Jinling; Feng, Juan; Shi, Qian; Tian, Xiaoyu

2017-11-01

This provides precious experience and reliable reference data for future design. This paper introduces the analysis process of Fan-blade-out, and considers the effect of windmill load on the fatigue lifespan of the case. According to Extended Operations (ETOPS) in the airworthiness regulations, the fatigue crack of it is analyzed by the unbalanced rotor load, during FBO. Compared with the lifespan in normal work of the engine, this research provides valuable design experience and reliable reference data for the case design in the near future.

In the DNA Exoneration Cases, Eyewitness Memory Was Not the Problem: A Reply to Berkowitz and Frenda (2018) and Wade, Nash, and Lindsay (2018).

PubMed

Wixted, John T; Mickes, Laura; Fisher, Ronald P

2018-05-01

The available real-world evidence suggests that, on an initial test, eyewitness memory is often reliable. Ironically, even the DNA exoneration cases-which generally involved nonpristine testing conditions and which are usually construed as an indictment of eyewitness memory-show how reliable an initial test of eyewitness memory can be in the real world. We endorse the use of pristine testing procedures, but their absence does not automatically imply that eyewitness memory is unreliable.

Tryptase, CD15 and IL-15 as reliable markers for the determination of soft and hard ligature marks vitality.

PubMed

Turillazzi, Emanuela; Vacchiano, Giuseppe; Luna-Maldonado, Aurelio; Neri, Margherita; Pomara, Cristoforo; Rabozzi, Roberto; Riezzo, Irene; Fineschi, Vittorio

2010-12-01

In forensic practice, it is required to distinguish between suicidal or accidental hanging and simulated hanging. Conventional macroscopic and histological findings may be unreliable; vital signs are often absent, and they can be produced postmortem. The application of immunohistochemical techniques opened up a new field of investigation in the issue of ligature marks. We investigated the immunohistochemical expression of a panel of cytokines and inflammatory cells in skin specimens in autopsy cases of death due to hanging, to discuss their significance in assessing whether hanging mark and signs occurred before or after the death of the victim. We selected 21 cases in which broad, soft and yielding materials were used and 28 cases in which materials used for hanging were hard. The control group included the following 21 cases: 14 cases of sudden cardiac death and 7 cases of post-mortem hanging (suspension) of bodies (drug overdose or suffocation as cause of death in all the cases). An immunohistochemical investigation of skin samples was performed utilizing antibodies anti- tryptase, fibronectin, TNFa, IL-6, IL-8, IL-10, MCP-1, IL-15, IL-1ß, CD45, CD4, CD3, CD8, CD68, CD20, CD15. We conclude that tryptase, IL-15, and CD15 appear to be reliable parameters in the determination of ligature marks' vitality with the accuracy needed for forensic purposes. This fact especially applies to soft marks which are particularly difficult to evaluate on the basis of gross examination and of conventional histological studies.

Learning from Adverse Events in Obstetrics: Is a Standardized Computer Tool an Effective Strategy for Root Cause Analysis?

PubMed

Murray-Davis, Beth; McDonald, Helen; Cross-Sudworth, Fiona; Ahmed, Rashid; Simioni, Julia; Dore, Sharon; Marrin, Michael; DeSantis, Judy; Leyland, Nicholas; Gardosi, Jason; Hutton, Eileen; McDonald, Sarah

2015-08-01

Adverse events occur in up to 10% of obstetric cases, and up to one half of these could be prevented. Case reviews and root cause analysis using a structured tool may help health care providers to learn from adverse events and to identify trends and recurring systems issues. We sought to establish the reliability of a root cause analysis computer application called Standardized Clinical Outcome Review (SCOR). We designed a mixed methods study to evaluate the effectiveness of the tool. We conducted qualitative content analysis of five charts reviewed by both the traditional obstetric quality assurance methods and the SCOR tool. We also determined inter-rater reliability by having four health care providers review the same five cases using the SCOR tool. The comparative qualitative review revealed that the traditional quality assurance case review process used inconsistent language and made serious, personalized recommendations for those involved in the case. In contrast, the SCOR review provided a consistent format for recommendations, a list of action points, and highlighted systems issues. The mean percentage agreement between the four reviewers for the five cases was 75%. The different health care providers completed data entry and assessment of the case in a similar way. Missing data from the chart and poor wording of questions were identified as issues affecting percentage agreement. The SCOR tool provides a standardized, objective, obstetric-specific tool for root cause analysis that may improve identification of risk factors and dissemination of action plans to prevent future events.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aita, J.F.; Keyes, J.W. Jr.

Two cases of acute infantile hemiplegia are presented. The first case is a patient with moyamoya disease with excellent correlation between the brain scan findings and her clinical signs and symptoms and the carotid arteriogram. The second patient had occlusive cerebrovascular disease secondary to thromboemboli with excellent correlation between the brain scan findings and his clinical state and the neuropathologic examination. In both cases the static brain scans and the radionuclide angiogram were comparable to those reported in adults with cerebrovascular disease both in appearance and in temporal sequence. Radionuclide studies can be an important and reliable diagnostic tool inmore » the evaluation of acute infantile hemiplegia. (auth)« less

The Trauma Symptom Checklist for Young Children (TSCYC): reliability and association with abuse exposure in a multi-site study.

PubMed

Briere, J; Johnson, K; Bissada, A; Damon, L; Crouch, J; Gil, E; Hanson, R; Ernst, V

2001-08-01

The Trauma Symptom Checklist for Young Children (TSCYC) is a 90-item caretaker-report measure of children's trauma- and abuse-related symptomatology. It contains two reporter validity scales and eight clinical scales [Post-traumatic Stress-Intrusion (PTS-I), Post-traumatic Stress-Avoidance (PTS-AV), Post-traumatic Stress-Arousal (PTS-AR), Post-traumatic Stress-Total (PTS-TOT), Sexual Concerns (SC), Dissociation (DIS), Anxiety (ANX), Depression (DEP), and Anger/Aggression (ANG)], as well as an item assessing hours per week of caretaker contact with the child. This paper introduces the TSCYC and describes its psychometric properties in a multisite validity study. A total of 219 TSCYCs administered by six clinician/researchers across the United States were analyzed for scale reliability and association with several types of childhood maltreatment. The TSCYC clinical scales have good reliability and are associated with exposure to childhood sexual abuse, physical abuse, and witnessing domestic violence. The PTS-I, PTS-AV, PTS-AR, and PTS-TOT scales were most predictive, followed by SC in the case of sexual abuse and DIS in the case of physical abuse. There were a small number of age, sex, and race effects on TSCYC scores. The TSCYC appears to have reasonable psychometric characteristics, and correlates as expected with various types of trauma exposure. Subject to continued validation and the development of general population norms, its use as a clinical measure is supported.

Non-contact ulcer area calculation system for neuropathic foot ulcer.

PubMed

Shah, Parth; Mahajan, Siddaram; Nageswaran, Sharmila; Paul, Sathish Kumar; Ebenzer, Mannam

2017-08-11

Around 125,785 new cases in year 2013-14 of leprosy were detected in India as per WHO report on leprosy in September 2015 which accounts to approximately 62% of the total new cases. Anaesthetic foot caused by leprosy leads to uneven loading of foot leading to ulcer in approximately 20% of the cases. Much efforts have gone in identifying newer techniques to efficiently monitor the progress of ulcer healing. Current techniques followed in measuring the size of ulcers, have not been found to be so accurate but are still is followed by clinicians across the globe. Quantification of prognosis of the condition would be required to understand the efficacy of current treatment methods and plan for further treatment. This study aims at developing a non contact technique to precisely measure the size of ulcer in patients affected by leprosy. Using MATLAB software, GUI was designed to process the acquired ulcer image by segmenting and calculating the pixel area of the image. The image was further converted to a standard measurement using a reference object. The developed technique was tested on 16 ulcer images acquired from 10 leprosy patients with plantar ulcers. Statistical analysis was done using MedCalc analysis software to find the reliability of the system. The analysis showed a very high correlation coefficient (r=0.9882) between the ulcer area measurements done using traditional technique and the newly developed technique, The reliability of the newly developed technique was significant with a significance level of 99.9%. The designed non-contact ulcer area calculating system using MATLAB is found to be a reliable system in calculating the size of ulcers. The technique would help clinicians have a reliable tool to monitor the progress of ulcer healing and help modify the treatment protocol if needed. Copyright © 2017 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

Balancing reliability and cost to choose the best power subsystem

NASA Technical Reports Server (NTRS)

Suich, Ronald C.; Patterson, Richard L.

1991-01-01

A mathematical model is presented for computing total (spacecraft) subsystem cost including both the basic subsystem cost and the expected cost due to the failure of the subsystem. This model is then used to determine power subsystem cost as a function of reliability and redundancy. Minimum cost and maximum reliability and/or redundancy are not generally equivalent. Two example cases are presented. One is a small satellite, and the other is an interplanetary spacecraft.

Reliability assessment of a multistate freight network for perishable merchandise with multiple suppliers and buyers

NASA Astrophysics Data System (ADS)

Lin, Yi-Kuei; Yeh, Cheng-Ta; Huang, Cheng-Fu

2017-01-01

This study develops a multistate freight network for single and perishable merchandise to assess the freight performance, where a node denotes a supplier, a distribution centre, or a buyer, while a logistics company providing a freight traffic service is denoted by an edge. For each logistics company, carrying capacity should be multistate since partial capacity may be reserved by some customers. The merchandise may perish or be perished during conveyance because of disadvantageous weather or collision in carrying such that the number of intact cargoes may be insufficient for the buyers. Hence, according to the perspective of supply chain management, the reliability, a probability of the network to successfully deliver the cargoes from the suppliers to the buyers subject to a budget, is proposed to be a performance index, where the suppliers and buyers are not the previous customers. An algorithm in terms of minimal paths to assess the reliability is developed. A fruit logistics case is adopted to explore the managerial implications of the reliability using sensitivity analysis.

Hybrid time-variant reliability estimation for active control structures under aleatory and epistemic uncertainties

NASA Astrophysics Data System (ADS)

Wang, Lei; Xiong, Chuang; Wang, Xiaojun; Li, Yunlong; Xu, Menghui

2018-04-01

Considering that multi-source uncertainties from inherent nature as well as the external environment are unavoidable and severely affect the controller performance, the dynamic safety assessment with high confidence is of great significance for scientists and engineers. In view of this, the uncertainty quantification analysis and time-variant reliability estimation corresponding to the closed-loop control problems are conducted in this study under a mixture of random, interval, and convex uncertainties. By combining the state-space transformation and the natural set expansion, the boundary laws of controlled response histories are first confirmed with specific implementation of random items. For nonlinear cases, the collocation set methodology and fourth Rounge-Kutta algorithm are introduced as well. Enlightened by the first-passage model in random process theory as well as by the static probabilistic reliability ideas, a new definition of the hybrid time-variant reliability measurement is provided for the vibration control systems and the related solution details are further expounded. Two engineering examples are eventually presented to demonstrate the validity and applicability of the methodology developed.

Phosphate analysis of natural sausage casings preserved in brines with phosphate additives as inactivating agent - Method validation.

PubMed

Wijnker, J J; Tjeerdsma-van Bokhoven, J L M; Veldhuizen, E J A

2009-01-01

Certain phosphates have been identified as suitable additives for the improvement of the microbial and mechanical properties of processed natural sausage casings. When mixed with NaCl (sodium chloride) and used under specific treatment and storage conditions, these phosphates are found to prevent the spread of foot-and-mouth disease and classical swine fever via treated casings. The commercially available Quantichrom™ phosphate assay kit has been evaluated as to whether it can serve as a reliable and low-tech method for routine analysis of casings treated with phosphate. The outcome of this study indicates that this particular assay kit has sufficient sensitivity to qualitatively determine the presence of phosphate in treated casings without interference of naturally occurring phosphate in salt used for brines in which casings are preserved.

77 FR 29644 - Agency Information Collection Activities: Proposed Collection; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-18

... reliability and construct validity of survey items and composites. (c) Case mix adjustment analysis--Assess the variables that may be considered as case mix adjusters. These preliminary research activities are...

A reliability analysis tool for SpaceWire network

NASA Astrophysics Data System (ADS)

Zhou, Qiang; Zhu, Longjiang; Fei, Haidong; Wang, Xingyou

2017-04-01

A SpaceWire is a standard for on-board satellite networks as the basis for future data-handling architectures. It is becoming more and more popular in space applications due to its technical advantages, including reliability, low power and fault protection, etc. High reliability is the vital issue for spacecraft. Therefore, it is very important to analyze and improve the reliability performance of the SpaceWire network. This paper deals with the problem of reliability modeling and analysis with SpaceWire network. According to the function division of distributed network, a reliability analysis method based on a task is proposed, the reliability analysis of every task can lead to the system reliability matrix, the reliability result of the network system can be deduced by integrating these entire reliability indexes in the matrix. With the method, we develop a reliability analysis tool for SpaceWire Network based on VC, where the computation schemes for reliability matrix and the multi-path-task reliability are also implemented. By using this tool, we analyze several cases on typical architectures. And the analytic results indicate that redundancy architecture has better reliability performance than basic one. In practical, the dual redundancy scheme has been adopted for some key unit, to improve the reliability index of the system or task. Finally, this reliability analysis tool will has a directive influence on both task division and topology selection in the phase of SpaceWire network system design.

The Miscalculation of Interrater Reliability: A Case Study Involving the AAC&U VALUE Rubrics

ERIC Educational Resources Information Center

Szafran, Robert F.

2017-01-01

Institutional assessment of student learning objectives has become a fact-of-life in American higher education and the Association of American Colleges and Universities' (AAC&U) VALUE Rubrics have become a widely adopted evaluation and scoring tool for student work. As faculty from a variety of disciplines, some less familiar with the…

Word-of-Mouth amongst Students at a New Zealand Tertiary Institution

ERIC Educational Resources Information Center

Warring, Susan

2013-01-01

Purpose: The aim of this case study was to investigate the extent of word-of-mouth influence amongst international students at a New Zealand tertiary institution and to review the literature for a valid and reliable conceptualisation and measurement of word-of-mouth. Design/methodology/approach: Literature suggests that opinion-leading and seeking…

Estimating Teacher Turnover Costs: A Case Study

ERIC Educational Resources Information Center

Levy, Abigail Jurist; Joy, Lois; Ellis, Pamela; Jablonski, Erica; Karelitz, Tzur M.

2012-01-01

High teacher turnover in large U.S. cities is a critical issue for schools and districts, and the students they serve; but surprisingly little work has been done to develop methodologies and standards that districts and schools can use to make reliable estimates of turnover costs. Even less is known about how to detect variations in turnover costs…

Leading in the 21st Century: Conceptualization of the Transformation of Higher Education and the Leadership Roles That Initiate These Changes

ERIC Educational Resources Information Center

Westover, Racheal R.

2016-01-01

This qualitative case study was proposed to gain understanding into how higher educational leaders perceive the transformation of their leadership roles and responsibilities. Leaders' accountabilities should be properly defined to establish a reliable and responsible association with all stakeholders affiliated with the institution. A lack of…

Personnel safety with pressurized gas systems

DOE PAGES

Cadwallader, Lee C.; Zhao, Haihua

2016-09-08

In this study, selected accident case histories are described that illustrate the potential modes of injury from gas jets, pressure-driven missiles, and asphyxiants. Gas combustion hazards are also briefly mentioned. Using high-pressure helium and nitrogen, estimates of safe exclusion distances are calculated for differing pressures, temperatures, and breach sizes. Some sources for gas system reliability values are also cited.

Reliability of skin biopsies in determining accurate tumor margins: a retrospective study after Mohs micrographic surgery.

PubMed

Koslosky, Cynthia Lynn; El Tal, Abdel Kader; Workman, Benjamin; Tamim, Hani; Durance, Michelle Christine; Mehregan, David Ali

2014-09-01

Skin biopsy reports of basal cell carcinoma and squamous cell carcinoma are often accompanied by comments on the margins. A physician's management can be influenced by such reports, particularly when the margins are reported as clear and no further interventions are pursued. To retrospectively review pathology margins on Mohs micrographic surgery (MMS) cases performed at a University Center and to compare biopsy margins with the Mohs margins found on the first stage. Data collection of 1,000 cases of Mohs surgery was obtained regarding margins on skin biopsy and compared with margins on the first stage of MMS. Overall, of the biopsies that showed only deep margin involvement, a lateral margin was seen on 32% of the first stages of MMS. Conversely, of the biopsies that showed only lateral margin involvement, a deep margin was seen on 14% of the first stages of MMS. Of the biopsies that showed clear margins, a margin was seen in 30% of the cases on the first stage of MMS. Skin biopsies processed through the "bread-loafing" technique are not reliable in detecting accurate margins, and therefore, a biopsy report should not include margin involvement within it.

Development and validation of surgical training tool: cystectomy assessment and surgical evaluation (CASE) for robot-assisted radical cystectomy for men.

PubMed

Hussein, Ahmed A; Sexton, Kevin J; May, Paul R; Meng, Maxwell V; Hosseini, Abolfazl; Eun, Daniel D; Daneshmand, Siamak; Bochner, Bernard H; Peabody, James O; Abaza, Ronney; Skinner, Eila C; Hautmann, Richard E; Guru, Khurshid A

2018-04-13

We aimed to develop a structured scoring tool: cystectomy assessment and surgical evaluation (CASE) that objectively measures and quantifies performance during robot-assisted radical cystectomy (RARC) for men. A multinational 10-surgeon expert panel collaborated towards development and validation of CASE. The critical steps of RARC in men were deconstructed into nine key domains, each assessed by five anchors. Content validation was done utilizing the Delphi methodology. Each anchor was assessed in terms of context, score concordance, and clarity. The content validity index (CVI) was calculated for each aspect. A CVI ≥ 0.75 represented consensus, and this statement was removed from the next round. This process was repeated until consensus was achieved for all statements. CASE was used to assess de-identified videos of RARC to determine reliability and construct validity. Linearly weighted percent agreement was used to assess inter-rater reliability (IRR). A logit model for odds ratio (OR) was used to assess construct validation. The expert panel reached consensus on CASE after four rounds. The final eight domains of the CASE included: pelvic lymph node dissection, development of the peri-ureteral space, lateral pelvic space, anterior rectal space, control of the vascular pedicle, anterior vesical space, control of the dorsal venous complex, and apical dissection. IRR > 0.6 was achieved for all eight domains. Experts outperformed trainees across all domains. We developed and validated a reliable structured, procedure-specific tool for objective evaluation of surgical performance during RARC. CASE may help differentiate novice from expert performances.

Validity and Reliability of the Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST) in University Students.

PubMed

Tiburcio Sainz, Marcela; Rosete-Mohedano, Ma Guadalupe; Natera Rey, Guillermina; Martínez Vélez, Nora Angélica; Carreño García, Silvia; Pérez Cisneros, Daniel

2016-03-02

The Alcohol, Smoking and Substance Involvement Screening Test (ASSIST), developed by the World Health Organization (WHO), has been used successfully in many countries, but there are few studies of its validity and reliability for the Mexican population. The objective of this study was to determine the psychometric properties of the self-administered ASSIST test in university students in Mexico. This was an ex post facto non-experimental study with 1,176 undergraduate students, the majority women (70.1%) aged 18-23 years (89.5%) and single (87.5%). To estimate concurrent validity, factor analysis and tests of reliability and correlation were carried out between the subscale for alcohol and AUDIT, those for tobacco and the Fagerström Test, and those for marijuana and DAST-20. Adequate reliability coefficients were obtained for ASSIST subscales for tobacco (alpha = 0.83), alcohol (alpha = 0.76), and marijuana (alpha = 0.73). Significant correlations were found only with the AUDIT (r = 0.71) and the alcohol subscale. The best balance of sensitivity and specificity of the alcohol subscale (83.8% and 80%, respectively) and the largest area under the ROC curve (81.9%) was found with a cutoff score of 8. The self-administered version of ASSIST is a valid screening instrument to identify at-risk cases due to substance use in this population.

Assessment of Semi-Structured Clinical Interview for Mobile Phone Addiction Disorder

PubMed Central

Alavi, Seyyed Salman; Jannatifard, Fereshteh; Mohammadi Kalhori, Soroush; Sepahbodi, Ghazal; BabaReisi, Mohammad; Sajedi, Sahar; Farshchi, Mojtaba; KhodaKarami, Rasul; Hatami Kasvaee, Vahid

2016-01-01

Objective: The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) classified mobile phone addiction disorder under “impulse control disorder not elsewhere classified”. This study surveyed the diagnostic criteria of DSM-IV-TR for the diagnosis of mobile phone addiction in correspondence with Iranian society and culture. Method: Two hundred fifty students of Tehran universities were entered into this descriptive-analytical and cross-sectional study. Quota sampling method was used. At first, semi- structured clinical interview (based on DSM-IV-TR) was performed for all the cases, and another specialist reevaluated the interviews. Data were analyzed using content validity, inter-scorer reliability (Kappa coefficient) and test-retest via SPSS18 software. Results: The content validity of the semi- structured clinical interview matched the DSM–IV-TR criteria for behavioral addiction. Moreover, their content was appropriate, and two items, including “SMS pathological use” and “High monthly cost of using the mobile phone” were added to promote its validity. Internal reliability (Kappa) and test–retest reliability were 0.55 and r = 0.4 (p<0. 01) respectively. Conclusion: The results of this study revealed that semi- structured diagnostic criteria of DSM-IV-TR are valid and reliable for diagnosing mobile phone addiction, and this instrument is an effective tool to diagnose this disorder. PMID:27437008

Assessment of a specifically developed bullet casing gun for the stunning of water buffaloes.

PubMed

Meichtry, Carmen; Glauser, Urs; Glardon, Matthieu; Ross, Steffen G; Lechner, Isabel; Kneubuehl, Beat P; Gascho, Dominic; Spadavecchia, Claudia; von Rotz, Alois; Stojiljkovic, Ana; Stoffel, Michael H

2018-01-01

Water buffaloes and cattle differ considerably with respect to the anatomy of the head. As a result, captive bolt stunners often fail to reliably produce adequate loss of consciousness in water buffaloes and, thus, do not fulfill animal welfare requirements. The goal of the present study was to assess and validate a new stunning device for water buffaloes meeting animal welfare and occupational safety requirements. The newly designed bullet casing gun uses .357Mag/10.2g hollow point bullets and has additional safety features. Its effectiveness and usability were assessed under practical conditions in an abattoir as based on widely accepted criteria. Stunning resulted in deep unconsciousness in 19 out of 20 water buffaloes. One 9-year old male did not immediately collapse. Except for very old bulls, the device presented herewith provides a means to stun water buffaloes of both sexes effectively and reliably while keeping occupational hazards to a minimum. Copyright © 2017 Elsevier Ltd. All rights reserved.

Processing and representation of meta-data for sleep apnea diagnosis with an artificial intelligence approach.

PubMed

Nettleton, D; Muñiz, J

2001-09-01

In this article, we revise and try to resolve some of the problems inherent in questionnaire screening of sleep apnea cases and apnea diagnosis based on attributes which are relevant and reliable. We present a way of learning information about the relevance of the data, comparing this with the definition of the information by the medical expert. We generate a predictive data model using a data aggregation operator which takes relevance and reliability information about the data into account to produce a diagnosis for each case. We also introduce a grade of membership for each question response which allows the patient to indicate a level of confidence or doubt in their own judgement. The method is tested with data collected from patients in a Sleep Clinic using questionnaires specially designed for the study. Other artificial intelligence predictive modeling algorithms are also tested on the same data and their predictive accuracy compared to that of the aggregation operator.

Perceptions of self, significant others, and teacher-child relationships in indiscriminately friendly children.

PubMed

Vervoort, Eleonora; Bosmans, Guy; Doumen, Sarah; Minnis, Helen; Verschueren, Karine

2014-11-01

Despite increasing research on indiscriminate friendliness in children, almost no research exists on social-cognitive deficits that are supposed to underlie indiscriminately friendly behavior. In this study, we compared indiscriminately friendly children with controls regarding their perceptions of self, reliability trust in significant others, and perceptions of the teacher-child relationship. Children's perceptions were compared in two samples: a sample of 33 likely cases for disinhibited reactive attachment disorder (RAD) from special education for children with emotional and behavioral disorders (75.76% boys, Mage=8.52, 96.9% Caucasian, 33.3% and 45.5% of their mothers completed primary or secondary education, respectively) was matched on sex, age, and socio-economic status with a sample of 33 controls from general education. Children participated individually in several interviews assessing global and social self-concept, reliability trust in significant others, teacher-child relationship perceptions, and vocabulary. Parents and teachers completed a screening questionnaire for RAD and the Strengths and Difficulties Questionnaire. Likely disinhibited RAD-cases showed more indiscriminate friendliness and more problem behavior in general according to their parents and teachers than controls. Furthermore, likely RAD-cases reported a more positive global self-concept, more reliability trust in significant others, and more dependency in the teacher-child relationship than controls. The results are in line with clinical observations of indiscriminately friendly children and findings in clinical samples of maltreated or attachment disrupted children but contrast hypotheses from developmental attachment research. Further research is needed to explain the more positive perceptions of indiscriminately friendly children. Copyright © 2014 Elsevier Ltd. All rights reserved.

A unique approach to quantifying the changing workload and case mix in laparoscopic colorectal surgery.

PubMed

Shah, P R; Gupta, V; Haray, P N

2011-03-01

Laparoscopic colorectal surgery includes a range of operations with differing technical difficulty, and traditional parameters, such as conversion and complication rates, may not be sensitive enough to assess the complexity of these procedures. This study aims to define a reproducible and reliable tool for quantifying the total workload and the complexity of the case mix. This is a review of a single surgeon's 10-year experience. The intermediate equivalent value scoring system was used to code complexity of cases. To assess changes in the workload and case mix, the period has been divided into five phases. Three hundred and forty-nine laparoscopic operations were performed, of which there were 264 (75.6%) resections. The overall conversion rate was 17.8%, with progressive improvement over the phases. Complex major operation (CMO), as defined in the British United Provident Association (BUPA) schedule of procedures, accounted for 35% of the workload. In spite of similar numbers of cases in each phase, there was a steady increase in the workload score, correlating with the increasing complexity of the case mix. There was no significant difference in the conversion and complications rates between CMO and non-CMO. The paradoxical increase in the mean operating time with increasing experience corresponded to the progressive increase in the workload score, reflecting the increasing complexity of the case mix. This article establishes a reliable and reproducible tool for quantifying the total laparoscopic colorectal workload of an individual surgeon or of an entire department, while at the same time providing a measure of the complexity of the case mix. © 2011 The Authors. Colorectal Disease © 2011 The Association of Coloproctology of Great Britain and Ireland.

Chemical and biological sensors based on defect-engineered graphene mesh field-effect transistors.

PubMed

Cho, Seunghee H; Kwon, Sun Sang; Yi, Jaeseok; Park, Won Il

2016-01-01

Graphene has been intensively studied for applications to high-performance sensors, but the sensing characteristics of graphene devices have varied from case to case, and the sensing mechanism has not been satisfactorily determined thus far. In this review, we describe recent progress in engineering of the defects in graphene grown by a silica-assisted chemical vapor deposition technique and elucidate the effect of the defects upon the electrical response of graphene sensors. This review provides guidelines for engineering and/or passivating defects to improve sensor performance and reliability.

Using minimal spanning trees to compare the reliability of network topologies

NASA Technical Reports Server (NTRS)

Leister, Karen J.; White, Allan L.; Hayhurst, Kelly J.

1990-01-01

Graph theoretic methods are applied to compute the reliability for several types of networks of moderate size. The graph theory methods used are minimal spanning trees for networks with bi-directional links and the related concept of strongly connected directed graphs for networks with uni-directional links. A comparison is conducted of ring networks and braided networks. The case is covered where just the links fail and the case where both links and nodes fail. Two different failure modes for the links are considered. For one failure mode, the link no longer carries messages. For the other failure mode, the link delivers incorrect messages. There is a description and comparison of link-redundancy versus path-redundancy as methods to achieve reliability. All the computations are carried out by means of a fault tree program.

Wireless and Powerless Sensing Node System Developed for Monitoring Motors.

PubMed

Lee, Dasheng

2008-08-27

Reliability and maintainability of tooling systems can be improved through condition monitoring of motors. However, it is difficult to deploy sensor nodes due to the harsh environment of industrial plants. Sensor cables are easily damaged, which renders the monitoring system deployed to assure the machine's reliability itself unreliable. A wireless and powerless sensing node integrated with a MEMS (Micro Electro-Mechanical System) sensor, a signal processor, a communication module, and a self-powered generator was developed in this study for implementation of an easily mounted network sensor for monitoring motors. A specially designed communication module transmits a sequence of electromagnetic (EM) pulses in response to the sensor signals. The EM pulses can penetrate through the machine's metal case and delivers signals from the sensor inside the motor to the external data acquisition center. By using induction power, which is generated by the motor's shaft rotation, the sensor node is self-sustaining; therefore, no power line is required. A monitoring system, equipped with novel sensing nodes, was constructed to test its performance. The test results illustrate that, the novel sensing node developed in this study can effectively enhance the reliability of the motor monitoring system and it is expected to be a valuable technology, which will be available to the plant for implementation in a reliable motor management program.

Feasibility of groundwater recharge dam projects in arid environments

NASA Astrophysics Data System (ADS)

Jaafar, H. H.

2014-05-01

A new method for determining feasibility and prioritizing investments for agricultural and domestic recharge dams in arid regions is developed and presented. The method is based on identifying the factors affecting the decision making process and evaluating these factors, followed by determining the indices in a GIS-aided environment. Evaluated parameters include results from field surveys and site visits, land cover and soils data, precipitation data, runoff data and modeling, number of beneficiaries, domestic irrigation demand, reservoir objectives, demography, reservoirs yield and reliability, dam structures, construction costs, and operation and maintenance costs. Results of a case study on more than eighty proposed dams indicate that assessment of reliability, annualized cost/demand satisfied and yield is crucial prior to investment decision making in arid areas. Irrigation demand is the major influencing parameter on yield and reliability of recharge dams, even when only 3 months of the demand were included. Reliability of the proposed reservoirs as related to their standardized size and net inflow was found to increase with increasing yield. High priority dams were less than 4% of the total, and less priority dams amounted to 23%, with the remaining found to be not feasible. The results of this methodology and its application has proved effective in guiding stakeholders for defining most favorable sites for preliminary and detailed design studies and commissioning.

Wireless and Powerless Sensing Node System Developed for Monitoring Motors

PubMed Central

Lee, Dasheng

2008-01-01

Reliability and maintainability of tooling systems can be improved through condition monitoring of motors. However, it is difficult to deploy sensor nodes due to the harsh environment of industrial plants. Sensor cables are easily damaged, which renders the monitoring system deployed to assure the machine's reliability itself unreliable. A wireless and powerless sensing node integrated with a MEMS (Micro Electro-Mechanical System) sensor, a signal processor, a communication module, and a self-powered generator was developed in this study for implementation of an easily mounted network sensor for monitoring motors. A specially designed communication module transmits a sequence of electromagnetic (EM) pulses in response to the sensor signals. The EM pulses can penetrate through the machine's metal case and delivers signals from the sensor inside the motor to the external data acquisition center. By using induction power, which is generated by the motor's shaft rotation, the sensor node is self-sustaining; therefore, no power line is required. A monitoring system, equipped with novel sensing nodes, was constructed to test its performance. The test results illustrate that, the novel sensing node developed in this study can effectively enhance the reliability of the motor monitoring system and it is expected to be a valuable technology, which will be available to the plant for implementation in a reliable motor management program. PMID:27873798

Reliability Prediction of Ontology-Based Service Compositions Using Petri Net and Time Series Models

PubMed Central

Li, Jia; Xia, Yunni; Luo, Xin

2014-01-01

OWL-S, one of the most important Semantic Web service ontologies proposed to date, provides a core ontological framework and guidelines for describing the properties and capabilities of their web services in an unambiguous, computer interpretable form. Predicting the reliability of composite service processes specified in OWL-S allows service users to decide whether the process meets the quantitative quality requirement. In this study, we consider the runtime quality of services to be fluctuating and introduce a dynamic framework to predict the runtime reliability of services specified in OWL-S, employing the Non-Markovian stochastic Petri net (NMSPN) and the time series model. The framework includes the following steps: obtaining the historical response times series of individual service components; fitting these series with a autoregressive-moving-average-model (ARMA for short) and predicting the future firing rates of service components; mapping the OWL-S process into a NMSPN model; employing the predicted firing rates as the model input of NMSPN and calculating the normal completion probability as the reliability estimate. In the case study, a comparison between the static model and our approach based on experimental data is presented and it is shown that our approach achieves higher prediction accuracy. PMID:24688429

Quality assurance study of caries risk assessment performance by clinical faculty members in a school of dentistry.

PubMed

Rechmann, Peter; Featherstone, John D B

2014-09-01

The goal of this quality assurance study was to explore the decision making of clinical faculty members at the University of California, San Francisco School of Dentistry predoctoral dental clinic in terms of caries risk level assignment using the caries risk assessment (CRA) as part of the Caries Management by Risk Assessment (CAMBRA) concept. This research was done in part to determine if additional training and calibration were needed for these faculty members. The study tested the reliability and reproducibility of the caries risk levels assigned by different clinical teachers who completed CRA forms for simulated patients. In the first step, five clinical teachers assigned caries risk levels for thirteen simulated patients. Six months later, the same five plus an additional nine faculty members assigned caries risk levels to the same thirteen simulated and nine additional cases. While the intra-examiner reliability with weighted kappa strength of agreement was very high, the inter-examiner agreements with a gold standard were on average only moderate. In total, 20 percent of the presented high caries risk cases were underestimated at caries levels too low, even when obvious caries disease indicators were present. This study suggests that more consistent training and calibration of clinical faculty members as well as students are needed.

A Fuzzy Robust Optimization Model for Waste Allocation Planning Under Uncertainty

PubMed Central

Xu, Ye; Huang, Guohe; Xu, Ling

2014-01-01

Abstract In this study, a fuzzy robust optimization (FRO) model was developed for supporting municipal solid waste management under uncertainty. The Development Zone of the City of Dalian, China, was used as a study case for demonstration. Comparing with traditional fuzzy models, the FRO model made improvement by considering the minimization of the weighted summation among the expected objective values, the differences between two extreme possible objective values, and the penalty of the constraints violation as the objective function, instead of relying purely on the minimization of expected value. Such an improvement leads to enhanced system reliability and the model becomes especially useful when multiple types of uncertainties and complexities are involved in the management system. Through a case study, the applicability of the FRO model was successfully demonstrated. Solutions under three future planning scenarios were provided by the FRO model, including (1) priority on economic development, (2) priority on environmental protection, and (3) balanced consideration for both. The balanced scenario solution was recommended for decision makers, since it respected both system economy and reliability. The model proved valuable in providing a comprehensive profile about the studied system and helping decision makers gain an in-depth insight into system complexity and select cost-effective management strategies. PMID:25317037

A Fuzzy Robust Optimization Model for Waste Allocation Planning Under Uncertainty.

PubMed

Xu, Ye; Huang, Guohe; Xu, Ling

2014-10-01

In this study, a fuzzy robust optimization (FRO) model was developed for supporting municipal solid waste management under uncertainty. The Development Zone of the City of Dalian, China, was used as a study case for demonstration. Comparing with traditional fuzzy models, the FRO model made improvement by considering the minimization of the weighted summation among the expected objective values, the differences between two extreme possible objective values, and the penalty of the constraints violation as the objective function, instead of relying purely on the minimization of expected value. Such an improvement leads to enhanced system reliability and the model becomes especially useful when multiple types of uncertainties and complexities are involved in the management system. Through a case study, the applicability of the FRO model was successfully demonstrated. Solutions under three future planning scenarios were provided by the FRO model, including (1) priority on economic development, (2) priority on environmental protection, and (3) balanced consideration for both. The balanced scenario solution was recommended for decision makers, since it respected both system economy and reliability. The model proved valuable in providing a comprehensive profile about the studied system and helping decision makers gain an in-depth insight into system complexity and select cost-effective management strategies.

A model of scientific attitudes assessment by observation in physics learning based scientific approach: case study of dynamic fluid topic in high school

NASA Astrophysics Data System (ADS)

Yusliana Ekawati, Elvin

2017-01-01

This study aimed to produce a model of scientific attitude assessment in terms of the observations for physics learning based scientific approach (case study of dynamic fluid topic in high school). Development of instruments in this study adaptation of the Plomp model, the procedure includes the initial investigation, design, construction, testing, evaluation and revision. The test is done in Surakarta, so that the data obtained are analyzed using Aiken formula to determine the validity of the content of the instrument, Cronbach’s alpha to determine the reliability of the instrument, and construct validity using confirmatory factor analysis with LISREL 8.50 program. The results of this research were conceptual models, instruments and guidelines on scientific attitudes assessment by observation. The construct assessment instruments include components of curiosity, objectivity, suspended judgment, open-mindedness, honesty and perseverance. The construct validity of instruments has been qualified (rated load factor > 0.3). The reliability of the model is quite good with the Alpha value 0.899 (> 0.7). The test showed that the model fits the theoretical models are supported by empirical data, namely p-value 0.315 (≥ 0.05), RMSEA 0.027 (≤ 0.08)

eLearning to facilitate the education and implementation of the Chelsea Critical Care Physical Assessment: a novel measure of function in critical illness

PubMed Central

Corner, Evelyn J; Handy, Jonathan M; Brett, Stephen J

2016-01-01

Objective To evaluate the efficacy of eLearning in the widespread standardised teaching, distribution and implementation of the Chelsea Critical Care Physical Assessment (CPAx) tool—a validated tool to assess physical function in critically ill patients. Design Prospective educational study. An eLearning module was developed through a conceptual framework, using the four-stage technique for skills teaching to teach clinicians how to use the CPAx. Example and test video case studies of CPAx assessments were embedded within the module. The CPAx scores for the test case studies and demographic data were recorded in a secure area of the website. Data were analysed for inter-rater reliability using intraclass correlation coefficients (ICCs) to see if an eLearning educational package facilitated consistent use of the tool. A utility and content validity questionnaire was distributed after 1 year to eLearning module registrants (n=971). This was to evaluate uptake of the CPAx in clinical practice and content validity of the CPAx from the perspective of clinical users. Setting The module was distributed for use via professional forums (n=2) and direct contacts (n=95). Participants Critical care clinicians. Primary outcome measure ICC of the test case studies. Results Between July and October 2014, 421 candidates from 15 countries registered for the eLearning module. The ICC for case one was 0.996 (95% CI 0.990 to 0.999; n=207). The ICC for case two was 0.988 (0.996 to 1.000; n=184). The CPAx has a strong total scale content validity index (s-CVI) of 0.94 and is well used. Conclusions eLearning is a useful and reliable way of teaching psychomotor skills, such as the CPAx. The CPAx is a well-used measure with high content validity rated by clinicians. PMID:27067895

eLearning to facilitate the education and implementation of the Chelsea Critical Care Physical Assessment: a novel measure of function in critical illness.

PubMed

Corner, Evelyn J; Handy, Jonathan M; Brett, Stephen J

2016-04-11

To evaluate the efficacy of eLearning in the widespread standardised teaching, distribution and implementation of the Chelsea Critical Care Physical Assessment (CPAx) tool-a validated tool to assess physical function in critically ill patients. Prospective educational study. An eLearning module was developed through a conceptual framework, using the four-stage technique for skills teaching to teach clinicians how to use the CPAx. Example and test video case studies of CPAx assessments were embedded within the module. The CPAx scores for the test case studies and demographic data were recorded in a secure area of the website. Data were analysed for inter-rater reliability using intraclass correlation coefficients (ICCs) to see if an eLearning educational package facilitated consistent use of the tool. A utility and content validity questionnaire was distributed after 1 year to eLearning module registrants (n=971). This was to evaluate uptake of the CPAx in clinical practice and content validity of the CPAx from the perspective of clinical users. The module was distributed for use via professional forums (n=2) and direct contacts (n=95). Critical care clinicians. ICC of the test case studies. Between July and October 2014, 421 candidates from 15 countries registered for the eLearning module. The ICC for case one was 0.996 (95% CI 0.990 to 0.999; n=207). The ICC for case two was 0.988 (0.996 to 1.000; n=184). The CPAx has a strong total scale content validity index (s-CVI) of 0.94 and is well used. eLearning is a useful and reliable way of teaching psychomotor skills, such as the CPAx. The CPAx is a well-used measure with high content validity rated by clinicians. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

A Case Study on the Application of a Structured Experimental Method for Optimal Parameter Design of a Complex Control System

NASA Technical Reports Server (NTRS)

Torres-Pomales, Wilfredo

2015-01-01

This report documents a case study on the application of Reliability Engineering techniques to achieve an optimal balance between performance and robustness by tuning the functional parameters of a complex non-linear control system. For complex systems with intricate and non-linear patterns of interaction between system components, analytical derivation of a mathematical model of system performance and robustness in terms of functional parameters may not be feasible or cost-effective. The demonstrated approach is simple, structured, effective, repeatable, and cost and time efficient. This general approach is suitable for a wide range of systems.

A case of persistent visual hallucinations of faces following LSD abuse: a functional Magnetic Resonance Imaging study.

PubMed

Iaria, Giuseppe; Fox, Christopher J; Scheel, Michael; Stowe, Robert M; Barton, Jason J S

2010-04-01

In this study, we report the case of a patient experiencing hallucinations of faces that could be reliably precipitated by looking at trees. Using functional Magnetic Resonance Imaging (fMRI), we found that face hallucinations were associated with increased and decreased neural activity in a number of cortical regions. Within the same fusiform face area, however, we found significant decreased and increased neural activity according to whether the patient was experiencing hallucinations or veridical perception of faces, respectively. These findings may indicate key differences in how hallucinatory and veridical perceptions lead to the same phenomenological experience of seeing faces.

Using Google Blogs and Discussions to Recommend Biomedical Resources: A Case Study

PubMed Central

Reed, Robyn B.; Chattopadhyay, Ansuman; Iwema, Carrie L.

2013-01-01

This case study investigated whether data gathered from discussions within the social media provide a reliable basis for a biomedical resources recommendation system. Using a search query to mine text from Google Blogs and Discussions, a ranking of biomedical resources was determined based on those most frequently mentioned. To establish quality, these results were compared to rankings by subject experts. An overall agreement between the frequency of social media discussions and subject expert recommendations was observed when identifying key bioinformatics and consumer health resources. Testing the method in more than one biomedical area implies this procedure could be employed across different subjects. PMID:24180648

The influence of validity criteria on Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) test-retest reliability among high school athletes.

PubMed

Brett, Benjamin L; Solomon, Gary S

2017-04-01

Research findings to date on the stability of Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) Composite scores have been inconsistent, requiring further investigation. The use of test validity criteria across these studies also has been inconsistent. Using multiple measures of stability, we examined test-retest reliability of repeated ImPACT baseline assessments in high school athletes across various validity criteria reported in previous studies. A total of 1146 high school athletes completed baseline cognitive testing using the online ImPACT test battery at two time periods of approximately two-year intervals. No participant sustained a concussion between assessments. Five forms of validity criteria used in previous test-retest studies were applied to the data, and differences in reliability were compared. Intraclass correlation coefficients (ICCs) ranged in composite scores from .47 (95% confidence interval, CI [.38, .54]) to .83 (95% CI [.81, .85]) and showed little change across a two-year interval for all five sets of validity criteria. Regression based methods (RBMs) examining the test-retest stability demonstrated a lack of significant change in composite scores across the two-year interval for all forms of validity criteria, with no cases falling outside the expected range of 90% confidence intervals. The application of more stringent validity criteria does not alter test-retest reliability, nor does it account for some of the variation observed across previously performed studies. As such, use of the ImPACT manual validity criteria should be utilized in the determination of test validity and in the individualized approach to concussion management. Potential future efforts to improve test-retest reliability are discussed.

Critical issues in assuring long lifetime and fail-safe operation of optical communications network

NASA Astrophysics Data System (ADS)

Paul, Dilip K.

1993-09-01

Major factors in assuring long lifetime and fail-safe operation in optical communications networks are reviewed in this paper. Reliable functionality to design specifications, complexity of implementation, and cost are the most critical issues. As economics is the driving force to set the goals as well as priorities for the design, development, safe operation, and maintenance schedules of reliable networks, a balance is sought between the degree of reliability enhancement, cost, and acceptable outage of services. Protecting both the link and the network with high reliability components, hardware duplication, and diversity routing can ensure the best network availability. Case examples include both fiber optic and lasercom systems. Also, the state-of-the-art reliability of photonics in space environment is presented.

Malaria remains a military medical problem.

PubMed

World, M J

2001-10-01

To bring military medical problems concerning malaria to the attention of the Defence Medical Services. Seven military medical problems related to malaria are illustrated by cases referred for secondary assessment over the past five years. Each is discussed in relation to published data. The cases of failure of various kinds of chemoprophylaxis, diagnosis and treatment of malaria may represent just a fraction of the magnitude of the overall problem but in the absence of reliable published military medical statistics concerning malaria cases, the situation is unclear. Present experience suggests there are a number of persisting problems affecting the military population in relation to malaria. Only publication of reliable statistics will define their magnitude. Interim remedies are proposed whose cost-effectiveness remains to be established.

Using meta-quality to assess the utility of volunteered geographic information for science.

PubMed

Langley, Shaun A; Messina, Joseph P; Moore, Nathan

2017-11-06

Volunteered geographic information (VGI) has strong potential to be increasingly valuable to scientists in collaboration with non-scientists. The abundance of mobile phones and other wireless forms of communication open up significant opportunities for the public to get involved in scientific research. As these devices and activities become more abundant, questions of uncertainty and error in volunteer data are emerging as critical components for using volunteer-sourced spatial data. Here we present a methodology for using VGI and assessing its sensitivity to three types of error. More specifically, this study evaluates the reliability of data from volunteers based on their historical patterns. The specific context is a case study in surveillance of tsetse flies, a health concern for being the primary vector of African Trypanosomiasis. Reliability, as measured by a reputation score, determines the threshold for accepting the volunteered data for inclusion in a tsetse presence/absence model. Higher reputation scores are successful in identifying areas of higher modeled tsetse prevalence. A dynamic threshold is needed but the quality of VGI will improve as more data are collected and the errors in identifying reliable participants will decrease. This system allows for two-way communication between researchers and the public, and a way to evaluate the reliability of VGI. Boosting the public's ability to participate in such work can improve disease surveillance and promote citizen science. In the absence of active surveillance, VGI can provide valuable spatial information given that the data are reliable.

[The Basel Screening Instrument for Psychosis (BSIP): development, structure, reliability and validity].

PubMed

Riecher-Rössler, A; Aston, J; Ventura, J; Merlo, M; Borgwardt, S; Gschwandtner, U; Stieglitz, R-D

2008-04-01

Early detection of psychosis is of growing clinical importance. So far there is, however, no screening instrument for detecting individuals with beginning psychosis in the atypical early stages of the disease with sufficient validity. We have therefore developed the Basel Screening Instrument for Psychosis (BSIP) and tested its feasibility, interrater-reliability and validity. Aim of this paper is to describe the development and structure of the instrument, as well as to report the results of the studies on reliability and validity. The instrument was developed based on a comprehensive search of literature on the most important risk factors and early signs of schizophrenic psychoses. The interraterreliability study was conducted on 24 psychiatric cases. Validity was tested based on 206 individuals referred to our early detection clinic from 3/1/2000 until 2/28/2003. We identified seven categories of relevance for early detection of psychosis and used them to construct a semistructured interview. Interrater-reliability for high risk individuals was high (Kappa .87). Predictive validity was comparable to other, more comprehensive instruments: 16 (32 %) of 50 individuals classified as being at risk for psychosis by the BSIP have in fact developed frank psychosis within an follow-up period of two to five years. The BSIP is the first screening instrument for the early detection of psychosis which has been validated based on transition to psychosis. The BSIP is easy to use by experienced psychiatrists and has a very good interrater-reliability and predictive validity.

Model uncertainty and multimodel inference in reliability estimation within a longitudinal framework.

PubMed

Alonso, Ariel; Laenen, Annouschka

2013-05-01

Laenen, Alonso, and Molenberghs (2007) and Laenen, Alonso, Molenberghs, and Vangeneugden (2009) proposed a method to assess the reliability of rating scales in a longitudinal context. The methodology is based on hierarchical linear models, and reliability coefficients are derived from the corresponding covariance matrices. However, finding a good parsimonious model to describe complex longitudinal data is a challenging task. Frequently, several models fit the data equally well, raising the problem of model selection uncertainty. When model uncertainty is high one may resort to model averaging, where inferences are based not on one but on an entire set of models. We explored the use of different model building strategies, including model averaging, in reliability estimation. We found that the approach introduced by Laenen et al. (2007, 2009) combined with some of these strategies may yield meaningful results in the presence of high model selection uncertainty and when all models are misspecified, in so far as some of them manage to capture the most salient features of the data. Nonetheless, when all models omit prominent regularities in the data, misleading results may be obtained. The main ideas are further illustrated on a case study in which the reliability of the Hamilton Anxiety Rating Scale is estimated. Importantly, the ambit of model selection uncertainty and model averaging transcends the specific setting studied in the paper and may be of interest in other areas of psychometrics. © 2012 The British Psychological Society.

Determinants of Quality of Interview and Impact on Risk Estimates in a Case-Control Study of Bladder Cancer

PubMed Central

Silverman, Debra T.; Malats, Núria; Tardon, Adonina; Garcia-Closas, Reina; Serra, Consol; Carrato, Alfredo; Fortuny, Joan; Rothman, Nathaniel; Dosemeci, Mustafa; Kogevinas, Manolis

2009-01-01

The authors evaluated potential determinants of the quality of the interview in a case-control study of bladder cancer and assessed the effect of the interview quality on the risk estimates. The analysis included 1,219 incident bladder cancer cases and 1,271 controls recruited in Spain in 1998–2001. Information on etiologic factors for bladder cancer was collected through personal interviews, which were scored as unsatisfactory, questionable, reliable, or high quality by the interviewers. Eight percent of the interviews were unsatisfactory or questionable. Increasing age, lower socioeconomic status, and poorer self-perceived health led to higher proportions of questionable or unreliable interviews. The odds ratio for cigarette smoking, the main risk factor for bladder cancer, was 6.18 (95% confidence interval: 4.56, 8.39) overall, 3.20 (95% confidence interval: 1.13, 9.04) among unsatisfactory or questionable interviews, 6.86 (95% confidence interval: 4.80, 9.82) among reliable interviews, and 7.70 (95% confidence interval: 3.64, 16.30) among high-quality interviews. Similar trends were observed for employment in high-risk occupations, drinking water containing elevated levels of trihalomethanes, and use of analgesics. Higher quality interviews led to stronger associations compared with risk estimation that did not take the quality of interview into account. The collection of quality of interview scores and the exclusion of unreliable interviews probably reduce misclassification of exposure in observational studies. PMID:19478234

Inter-rater agreement in evaluation of disability: systematic review of reproducibility studies.

PubMed

Barth, Jürgen; de Boer, Wout E L; Busse, Jason W; Hoving, Jan L; Kedzia, Sarah; Couban, Rachel; Fischer, Katrin; von Allmen, David Y; Spanjer, Jerry; Kunz, Regina

2017-01-25

 To explore agreement among healthcare professionals assessing eligibility for work disability benefits.  Systematic review and narrative synthesis of reproducibility studies.  Medline, Embase, and PsycINFO searched up to 16 March 2016, without language restrictions, and review of bibliographies of included studies.  Observational studies investigating reproducibility among healthcare professionals performing disability evaluations using a global rating of working capacity and reporting inter-rater reliability by a statistical measure or descriptively. Studies could be conducted in insurance settings, where decisions on ability to work include normative judgments based on legal considerations, or in research settings, where decisions on ability to work disregard normative considerations. : Teams of paired reviewers identified eligible studies, appraised their methodological quality and generalisability, and abstracted results with pretested forms. As heterogeneity of research designs and findings impeded a quantitative analysis, a descriptive synthesis stratified by setting (insurance or research) was performed.  From 4562 references, 101 full text articles were reviewed. Of these, 16 studies conducted in an insurance setting and seven in a research setting, performed in 12 countries, met the inclusion criteria. Studies in the insurance setting were conducted with medical experts assessing claimants who were actual disability claimants or played by actors, hypothetical cases, or short written scenarios. Conditions were mental (n=6, 38%), musculoskeletal (n=4, 25%), or mixed (n=6, 38%). Applicability of findings from studies conducted in an insurance setting to real life evaluations ranged from generalisable (n=7, 44%) and probably generalisable (n=3, 19%) to probably not generalisable (n=6, 37%). Median inter-rater reliability among experts was 0.45 (range intraclass correlation coefficient 0.86 to κ-0.10). Inter-rater reliability was poor in six studies (37%) and excellent in only two (13%). This contrasts with studies conducted in the research setting, where the median inter-rater reliability was 0.76 (range 0.91-0.53), and 71% (5/7) studies achieved excellent inter-rater reliability. Reliability between assessing professionals was higher when the evaluation was guided by a standardised instrument (23 studies, P=0.006). No such association was detected for subjective or chronic health conditions or the studies' generalisability to real world evaluation of disability (P=0.46, 0.45, and 0.65, respectively).  Despite their common use and far reaching consequences for workers claiming disabling injury or illness, research on the reliability of medical evaluations of disability for work is limited and indicates high variation in judgments among assessing professionals. Standardising the evaluation process could improve reliability. Development and testing of instruments and structured approaches to improve reliability in evaluation of disability are urgently needed. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Combine Flash-Based FPGA TID and Long-Term Retention Reliabilities Through VT Shift

NASA Astrophysics Data System (ADS)

Wang, Jih-Jong; Rezzak, Nadia; Dsilva, Durwyn; Xue, Fengliang; Samiee, Salim; Singaraju, Pavan; Jia, James; Nguyen, Victor; Hawley, Frank; Hamdy, Esmat

2016-08-01

Reliability test results of data retention and total ionizing dose (TID) in 65 nm Flash-based field programmable gate array (FPGA) are presented. Long-chain inverter design is recommended for reliability evaluation because it is the worst case design for both effects. Based on preliminary test data, both issues are unified and modeled by one natural decay equation. The relative contributions of TID induced threshold-voltage shift and retention mechanisms are evaluated by analyzing test data.

[Quality assurance in coding expertise of hospital cases in the German DRG system. Evaluation of inter-rater reliability in MDK expertise].

PubMed

Huber, H; Brambrink, M; Funk, R; Rieger, M

2012-10-01

The purpose of this study was to evaluate differences in the D-DRG results of a hospital case by 2 independently coding MKD raters. Calculation of the 2-inter-rater reliability was performed by examination of the coding of individual hospital cases. The reasons for the non-agreement of the expert evaluations and suggestions to improve the process are discussed. From the expert evaluation pool of the MDK-WL a random sample of 0.7% of the 57,375 expertises was taken. Distribution equality with the basic total was tested by the χ² test or, respectively, Fisher's exact test. For the total of 402 individual hospital cases, the G-DRG case sums of 2 experts of the MDK were determined independently and the results checked for each individual case for agreement or non-agreement. The corresponding confidence intervals with standard errors were analysed to test if certain major diagnosis categories (MDC) were statistically significantly more affected by differing expertise results than others. In 280 of the total 402 tested hospital cases, the 2 MDK raters independently reached the same G-DRG results; in 122 cases the G-DRG case sums determined by the 2 raters differed (agreement 70%; CI 65.2-74.1). Different DRG results between the 2 experts occurred regularly in the entire MDC spectrum. No MDC chapter in which significant differences between the 2 raters arose could be identified. The results of our study demonstrate an almost 70% agreement in the evaluation of hospital cost accounts by 2 independently operating MDK. This result leaves room for improvement. Optimisation potentials can be recognised on the basis of the results. Potential for improvement was established in combination with regular further training and the expansion of binding internal code recommendations as well as exchange of code-relevant information among experts in internal forums. The presented model is in principle suitable for cross-border examinations within the MDK system with the advantage that further trends could be uncovered by more variety and larger numbers of the randomly selected cases. © Georg Thieme Verlag KG Stuttgart · New York.

Modeling and projection of dengue fever cases in Guangzhou based on variation of weather factors.

PubMed

Li, Chenlu; Wang, Xiaofeng; Wu, Xiaoxu; Liu, Jianing; Ji, Duoying; Du, Juan

2017-12-15

Dengue fever is one of the most serious vector-borne infectious diseases, especially in Guangzhou, China. Dengue viruses and their vectors Aedes albopictus are sensitive to climate change primarily in relation to weather factors. Previous research has mainly focused on identifying the relationship between climate factors and dengue cases, or developing dengue case models with some non-climate factors. However, there has been little research addressing the modeling and projection of dengue cases only from the perspective of climate change. This study considered this topic using long time series data (1998-2014). First, sensitive weather factors were identified through meta-analysis that included literature review screening, lagged analysis, and collinear analysis. Then, key factors that included monthly average temperature at a lag of two months, and monthly average relative humidity and monthly average precipitation at lags of three months were determined. Second, time series Poisson analysis was used with the generalized additive model approach to develop a dengue model based on key weather factors for January 1998 to December 2012. Data from January 2013 to July 2014 were used to validate that the model was reliable and reasonable. Finally, future weather data (January 2020 to December 2070) were input into the model to project the occurrence of dengue cases under different climate scenarios (RCP 2.6 and RCP 8.5). Longer time series analysis and scientifically selected weather variables were used to develop a dengue model to ensure reliability. The projections suggested that seasonal disease control (especially in summer and fall) and mitigation of greenhouse gas emissions could help reduce the incidence of dengue fever. The results of this study hope to provide a scientifically theoretical basis for the prevention and control of dengue fever in Guangzhou. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluation of latex agglutination test (KAtex) for early diagnosis of kala-azar.

PubMed

Ahsan, M M; Islam, M N; Mollah, A H; Hoque, M A; Hossain, M A; Begum, Z; Islam, M T

2010-07-01

Kala-azar is one of the major public health problem in Bangladesh. But the diagnosis of the problem often is difficult, unusual and time consuming, a simple, noninvasive, easy to perform, reliable and rapid diagnostic test has been a long-felt need of the clinicians. Therefore, the present study was conducted to see the sensitivity and specificity of Latex Agglutination test (KAtex) to detect leishmanial antigen from urine of kala-azar cases. The study was carried out in the department of Paediatrics, Mymensingh Medical College and Hospital, Bangladesh during July to December, 2008. A total of 100 urine samples were collected of which 50 were confirmed kala-azar cases and 50 were age and sex matched controls. Out of 50 kala-azar cases 47 showed positive result of KAtex. The test was also positive in 01 out of 30 healthy controls. None of the febrile controls was positive by KAtex. The sensitivity, specificity, positive predictive value and negative predictive value of the test using presence of LD bodies in splenic and/or bone marrow aspirate as gold standard were 94%, 98%, 97.91% and 94.23% respectively. KAtex is simple, noninvasive, easy to perform, rapid and reliable test for diagnosing kala-azar in endemic area and useful for small, less equipped laboratories as well as for the laboratories with better facilities.

Estimating the reliability of repeatedly measured endpoints based on linear mixed-effects models. A tutorial.

PubMed

Van der Elst, Wim; Molenberghs, Geert; Hilgers, Ralf-Dieter; Verbeke, Geert; Heussen, Nicole

2016-11-01

There are various settings in which researchers are interested in the assessment of the correlation between repeated measurements that are taken within the same subject (i.e., reliability). For example, the same rating scale may be used to assess the symptom severity of the same patients by multiple physicians, or the same outcome may be measured repeatedly over time in the same patients. Reliability can be estimated in various ways, for example, using the classical Pearson correlation or the intra-class correlation in clustered data. However, contemporary data often have a complex structure that goes well beyond the restrictive assumptions that are needed with the more conventional methods to estimate reliability. In the current paper, we propose a general and flexible modeling approach that allows for the derivation of reliability estimates, standard errors, and confidence intervals - appropriately taking hierarchies and covariates in the data into account. Our methodology is developed for continuous outcomes together with covariates of an arbitrary type. The methodology is illustrated in a case study, and a Web Appendix is provided which details the computations using the R package CorrMixed and the SAS software. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Within-Session Stability of Short-Term Heart Rate Variability Measurement

PubMed Central

2016-01-01

Abstract The primary aim of this study was to assess the retest stability of the short-term heart rate variability (HRV) measurement performed within one session and without the use of any intervention. Additionally, a precise investigation of the possible impact of intrinsic biological variation on HRV reliability was also performed. First, a single test-retest HRV measurement was conducted with 20-30 min apart from one another. Second, the HRV measurement was repeated in ten non-interrupted consecutive intervals. The lowest typical error (CV = 21.1%) was found for the square root of the mean squared differences of successive RR intervals (rMSSD) and the highest for the low frequency power (PLF) (CV = 93.9%). The standardized changes in the mean were trivial to small. The correlation analysis revealed the highest level for ln rMSSD (ICC = 0.87), while ln PLF represented the worst case (ICC = 0.59). The reliability indices for ln rMSSD in 10 consecutive intervals improved (CV = 9.9%; trivial standardized changes in the mean; ICC = 0.96). In conclusion, major differences were found in the reliability level between the HRV indices. The rMSSD demonstrated the highest reliability level. No substantial influence of intrinsic biological variation on the HRV reliability was observed. PMID:28149345

Reliability and Model Fit

ERIC Educational Resources Information Center

Stanley, Leanne M.; Edwards, Michael C.

2016-01-01

The purpose of this article is to highlight the distinction between the reliability of test scores and the fit of psychometric measurement models, reminding readers why it is important to consider both when evaluating whether test scores are valid for a proposed interpretation and/or use. It is often the case that an investigator judges both the…

Standardized Patients Provide a Reliable Assessment of Athletic Training Students' Clinical Skills

ERIC Educational Resources Information Center

Armstrong, Kirk J.; Jarriel, Amanda J.

2016-01-01

Context: Providing students reliable objective feedback regarding their clinical performance is of great value for ongoing clinical skill assessment. Since a standardized patient (SP) is trained to consistently portray the case, students can be assessed and receive immediate feedback within the same clinical encounter; however, no research, to our…

Establishing the Validity and Reliability of Course Evaluation Questionnaires

ERIC Educational Resources Information Center

Kember, David; Leung, Doris Y. P.

2008-01-01

This article uses the case of designing a new course questionnaire to discuss the issues of validity, reliability and diagnostic power in good questionnaire design. Validity is often not well addressed in course questionnaire design as there are no straightforward tests that can be applied to an individual instrument. The authors propose the…

Development of confidence limits by pivotal functions for estimating software reliability

NASA Technical Reports Server (NTRS)

Dotson, Kelly J.

1987-01-01

The utility of pivotal functions is established for assessing software reliability. Based on the Moranda geometric de-eutrophication model of reliability growth, confidence limits for attained reliability and prediction limits for the time to the next failure are derived using a pivotal function approach. Asymptotic approximations to the confidence and prediction limits are considered and are shown to be inadequate in cases where only a few bugs are found in the software. Departures from the assumed exponentially distributed interfailure times in the model are also investigated. The effect of these departures is discussed relative to restricting the use of the Moranda model.

Systems engineering principles for the design of biomedical signal processing systems.

PubMed

Faust, Oliver; Acharya U, Rajendra; Sputh, Bernhard H C; Min, Lim Choo

2011-06-01

Systems engineering aims to produce reliable systems which function according to specification. In this paper we follow a systems engineering approach to design a biomedical signal processing system. We discuss requirements capturing, specification definition, implementation and testing of a classification system. These steps are executed as formal as possible. The requirements, which motivate the system design, are based on diabetes research. The main requirement for the classification system is to be a reliable component of a machine which controls diabetes. Reliability is very important, because uncontrolled diabetes may lead to hyperglycaemia (raised blood sugar) and over a period of time may cause serious damage to many of the body systems, especially the nerves and blood vessels. In a second step, these requirements are refined into a formal CSP‖ B model. The formal model expresses the system functionality in a clear and semantically strong way. Subsequently, the proven system model was translated into an implementation. This implementation was tested with use cases and failure cases. Formal modeling and automated model checking gave us deep insight in the system functionality. This insight enabled us to create a reliable and trustworthy implementation. With extensive tests we established trust in the reliability of the implementation. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Reliability of implant placement after virtual planning of implant positions using cone beam CT data and surgical (guide) templates.

PubMed

Nickenig, Hans-Joachim; Eitner, Stephan

2007-01-01

We assessed the reliability of implant placement after virtual planning of implant positions using cone-beam CT data and surgical guide templates. A total of 102 patients (250 implants, 55.4% mandibular; mean patient age, 40.4 years) who had undergone implant treatment therapy in an armed forces dental clinic (Cologne, Germany) between July 1, 2005 and December 1, 2005. They were treated with a system that allows transfer of virtual planning to surgical guide templates. Only in eight cases the surgical guides were not used because a delayed implant placement was necessary. In four posterior mandibular cases, handling was limited because of reduced interocclusal distance, requiring 50% shortening of the drill guides. The predictability of implant size was high: only one implant was changed to a smaller diameter (because of insufficient bone). In all cases, critical anatomical structures were protected and no complications were detected in postoperative panoramic radiographs. In 58.1% (147) of the 250 implants, a flapless surgery plan was realized. Implant placement after virtual planning of implant positions using cone beam CT data and surgical templates can be reliable for preoperative assessment of implant size, position, and anatomical complications. It is also indicative of cases amenable to flapless surgery.

Is case-specificity content-specificity? An analysis of data from extended-matching questions.

PubMed

Dory, Valerie; Gagnon, Robert; Charlin, Bernard

2010-03-01

Case-specificity, i.e., variability of a subject's performance across cases, has been a consistent finding in medical education. It has important implications for assessment validity and reliability. Its root causes remain a matter of discussion. One hypothesis, content-specificity, links variability of performance to variable levels of relevant knowledge. Extended-matching items (EMIs) are an ideal format to test this hypothesis as items are grouped by topic. If differences pertaining to content knowledge are the main cause of case-specificity, variability across topics should be high and variability across items within the same topic low. We used generalisability analysis on results of a written test composed of 159 EMIs sat by two cohorts of general practice trainees at one university. Two hundred and twenty-seven trainees took part. The variance component attributed to subjects was small. Variance attributed to topics was smaller than variance attributed to items. The main source of error was interaction between subjects and items, accounting for two-thirds of error. The generalisability D study revealed that for the same total number of items, increasing the number of topics results in a higher G coefficient than increasing the number of items per topic. Topical knowledge does not seem to explain case-specificity observed in our data. Structure of knowledge and reasoning strategy may be more important, in particular pattern-recognition which EMIs were designed to elicit. The causal explanations of case-specificity may be dependent on test format. Increasing the number of topics with fewer items each would increase reliability but also testing time.

Co-evolving prisoner's dilemma: Performance indicators and analytic approaches

NASA Astrophysics Data System (ADS)

Zhang, W.; Choi, C. W.; Li, Y. S.; Xu, C.; Hui, P. M.

2017-02-01

Understanding the intrinsic relation between the dynamical processes in a co-evolving network and the necessary ingredients in formulating a reliable theory is an important question and a challenging task. Using two slightly different definitions of performance indicator in the context of a co-evolving prisoner's dilemma game, it is shown that very different cooperative levels result and theories of different complexity are required to understand the key features. When the payoff per opponent is used as the indicator (Case A), non-cooperative strategy has an edge and dominates in a large part of the parameter space formed by the cutting-and-rewiring probability and the strategy imitation probability. When the payoff from all opponents is used (Case B), cooperative strategy has an edge and dominates the parameter space. Two distinct phases, one homogeneous and dynamical and another inhomogeneous and static, emerge and the phase boundary in the parameter space is studied in detail. A simple theory assuming an average competing environment for cooperative agents and another for non-cooperative agents is shown to perform well in Case A. The same theory, however, fails badly for Case B. It is necessary to include more spatial correlation into a theory for Case B. We show that the local configuration approximation, which takes into account of the different competing environments for agents with different strategies and degrees, is needed to give reliable results for Case B. The results illustrate that formulating a proper theory requires both a conceptual understanding of the effects of the adaptive processes in the problem and a delicate balance between simplicity and accuracy.

An acoustic streaming instability in thermoacoustic devices utilizing jet pumps.

PubMed

Backhaus, S; Swift, G W

2003-03-01

Thermoacoustic-Stirling hybrid engines and feedback pulse tube refrigerators can utilize jet pumps to suppress streaming that would otherwise cause large heat leaks and reduced efficiency. It is desirable to use jet pumps to suppress streaming because they do not introduce moving parts such as bellows or membranes. In most cases, this form of streaming suppression works reliably. However, in some cases, the streaming suppression has been found to be unstable. Using a simple model of the acoustics in the regenerators and jet pumps of these devices, a stability criterion is derived that predicts when jet pumps can reliably suppress streaming.

Reducing case ascertainment costs in US population studies of Alzheimer's disease, dementia, and cognitive impairment—Part 1*

PubMed Central

Weir, David R.; Wallace, Robert B.; Langa, Kenneth M.; Plassman, Brenda L.; Wilson, Robert S.; Bennett, David A.; Duara, Ranjan; Loewenstein, David; Ganguli, Mary; Sano, Mary

2011-01-01

Establishing methods for ascertainment of dementia and cognitive impairment that are accurate and also cost effective is a challenging enterprise. Large population-based studies often using administrative data sets offer relatively inexpensive but reliable estimates of severe conditions including moderate to advanced dementia that are useful for public health planning, but they can miss less severe cognitive impairment which may be the most effective point for intervention. Clinical and epidemiological cohorts, intensively assessed, provide more sensitive detection of less severe cognitive impairment but are often costly. Here, several approaches to ascertainment are evaluated for validity, reliability, and cost. In particular, the methods of ascertainment from the Health and Retirement Study (HRS) are described briefly, along with those of the Aging, Demographics, and Memory Study (ADAMS). ADAMS, a resource-intense sub-study of the HRS, was designed to provide diagnostic accuracy among persons with more advanced dementia. A proposal to streamline future ADAMS assessments is offered. Also considered are decision tree, algorithmic, and web-based approaches to diagnosis that can reduce the expense of clinical expertise and, in some contexts, can reduce the extent of data collection. These approaches are intended for intensively assessed epidemiological cohorts. The goal is valid and reliable detection with efficient and cost-effective tools. PMID:21255747

Quantifying the test-retest reliability of cerebral blood flow measurements in a clinical model of on-going post-surgical pain: A study using pseudo-continuous arterial spin labelling.

PubMed

Hodkinson, Duncan J; Krause, Kristina; Khawaja, Nadine; Renton, Tara F; Huggins, John P; Vennart, William; Thacker, Michael A; Mehta, Mitul A; Zelaya, Fernando O; Williams, Steven C R; Howard, Matthew A

2013-01-01

Arterial spin labelling (ASL) is increasingly being applied to study the cerebral response to pain in both experimental human models and patients with persistent pain. Despite its advantages, scanning time and reliability remain important issues in the clinical applicability of ASL. Here we present the test-retest analysis of concurrent pseudo-continuous ASL (pCASL) and visual analogue scale (VAS), in a clinical model of on-going pain following third molar extraction (TME). Using ICC performance measures, we were able to quantify the reliability of the post-surgical pain state and ΔCBF (change in CBF), both at the group and individual case level. Within-subject, the inter- and intra-session reliability of the post-surgical pain state was ranked good-to-excellent (ICC > 0.6) across both pCASL and VAS modalities. The parameter ΔCBF (change in CBF between pre- and post-surgical states) performed reliably (ICC > 0.4), provided that a single baseline condition (or the mean of more than one baseline) was used for subtraction. Between-subjects, the pCASL measurements in the post-surgical pain state and ΔCBF were both characterised as reliable (ICC > 0.4). However, the subjective VAS pain ratings demonstrated a significant contribution of pain state variability, which suggests diminished utility for interindividual comparisons. These analyses indicate that the pCASL imaging technique has considerable potential for the comparison of within- and between-subjects differences associated with pain-induced state changes and baseline differences in regional CBF. They also suggest that differences in baseline perfusion and functional lateralisation characteristics may play an important role in the overall reliability of the estimated changes in CBF. Repeated measures designs have the important advantage that they provide good reliability for comparing condition effects because all sources of variability between subjects are excluded from the experimental error. The ability to elicit reliable neural correlates of on-going pain using quantitative perfusion imaging may help support the conclusions derived from subjective self-report.

Reliability study of tibialis posterior and selected leg muscle EMG and multi-segment foot kinematics in rheumatoid arthritis associated pes planovalgus

PubMed Central

Barn, Ruth; Rafferty, Daniel; Turner, Deborah E.; Woodburn, James

2012-01-01

Objective To determine within- and between-day reliability characteristics of electromyographic (EMG) activity patterns of selected lower leg muscles and kinematic variables in patients with rheumatoid arthritis (RA) and pes planovalgus. Methods Five patients with RA underwent gait analysis barefoot and shod on two occasions 1 week apart. Fine-wire (tibialis posterior [TP]) and surface EMG for selected muscles and 3D kinematics using a multi-segmented foot model was undertaken barefoot and shod. Reliability of pre-determined variables including EMG activity patterns and inter-segment kinematics were analysed using coefficients of multiple correlation, intraclass correlation coefficients (ICC) and the standard error of the measurement (SEM). Results Muscle activation patterns within- and between-day ranged from fair-to-good to excellent in both conditions. Discrete temporal and amplitude variables were highly variable across all muscle groups in both conditions but particularly poor for TP and peroneus longus. SEMs ranged from 1% to 9% of stance and 4% to 27% of maximum voluntary contraction; in most cases the 95% confidence interval crossed zero. Excellent within-day reliability was found for the inter-segment kinematics in both conditions. Between-day reliability ranged from fair-to-good to excellent for kinematic variables and all ICCs were excellent; the SEM ranged from 0.60° to 1.99°. Conclusion Multi-segmented foot kinematics can be reliably measured in RA patients with pes planovalgus. Serial measurement of discrete variables for TP and other selected leg muscles via EMG is not supported from the findings in this cohort of RA patients. Caution should be exercised when EMG measurements are considered to study disease progression or intervention effects. PMID:22721819

Measurement of the Inter-Rater Reliability Rate Is Mandatory for Improving the Quality of a Medical Database: Experience with the Paulista Lung Cancer Registry.

PubMed

Lauricella, Leticia L; Costa, Priscila B; Salati, Michele; Pego-Fernandes, Paulo M; Terra, Ricardo M

2018-06-01

Database quality measurement should be considered a mandatory step to ensure an adequate level of confidence in data used for research and quality improvement. Several metrics have been described in the literature, but no standardized approach has been established. We aimed to describe a methodological approach applied to measure the quality and inter-rater reliability of a regional multicentric thoracic surgical database (Paulista Lung Cancer Registry). Data from the first 3 years of the Paulista Lung Cancer Registry underwent an audit process with 3 metrics: completeness, consistency, and inter-rater reliability. The first 2 methods were applied to the whole data set, and the last method was calculated using 100 cases randomized for direct auditing. Inter-rater reliability was evaluated using percentage of agreement between the data collector and auditor and through calculation of Cohen's κ and intraclass correlation. The overall completeness per section ranged from 0.88 to 1.00, and the overall consistency was 0.96. Inter-rater reliability showed many variables with high disagreement (>10%). For numerical variables, intraclass correlation was a better metric than inter-rater reliability. Cohen's κ showed that most variables had moderate to substantial agreement. The methodological approach applied to the Paulista Lung Cancer Registry showed that completeness and consistency metrics did not sufficiently reflect the real quality status of a database. The inter-rater reliability associated with κ and intraclass correlation was a better quality metric than completeness and consistency metrics because it could determine the reliability of specific variables used in research or benchmark reports. This report can be a paradigm for future studies of data quality measurement. Copyright © 2018 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Assessment of the functional significance of coronary lesions using a monorail catheter.

PubMed

Briguori, C; Nishida, T; Adamian, M; Anzuini, A; Corvaja, N; Carlino, M; Colombo, A

2001-04-01

Myocardial fractional flow reserve (FFR) < 0.75 is a reliable index of a functionally severe coronary stenosis. FFR is best assessed by a sensor-tipped pressure monitoring guidewire (PW). The purpose of this study was to assess whether a multifunctional probing catheter (MFP), a 3 French dual-lumen monorail catheter, can be used to accurately measure intracoronary pressure and FFR. In 35 lesions (35 patients; learning group), we calculated FFR by both PW (FFRPW) and MFP (FFRMFP). Using ROC analysis, the FFRMFP value of 0.65 had the highest sensitivity with the FFRPW < 0.75. FFRMFP cut-off (0.65) was tested in 40 patients (testing group). In all cases, lumen diameter was documented by an intracoronary ultrasound examination. In the learning group, the FFRPW was 0.82 +/- 0.17 and FFRMFP was 0.70 +/- 0.23 (r = 0.88; p < 0.001). The FFRMFP cut-off value (0.65) correctly predicted the FFRPW in 37/40 cases in the testing group. In the 3 discordant cases, FFR was critical (< 0.65) by MFP and normal (> 0.75) by PW. In all these cases, minimal lumen cross-sectional area was < 2.8 mm2. When FFRMFP is > 0.65, FFRPW is always > 0.75. These data demonstrate that even with larger cross-sectional area than a pressure wire, the MFP catheter can easily and reliably be used to assess the functional severity of coronary stenosis.

Reliability and accuracy of sleep apnea scans in novel cardiac resynchronization therapy devices: an independent report of two cases.

PubMed

Fox, Henrik; Nölker, Georg; Gutleben, Klaus-Jürgen; Bitter, Thomas; Horstkotte, Dieter; Oldenburg, Olaf

2014-03-01

Pacemaker apnea scan algorithms are able to screen for sleep apnea. We investigated whether these systems were able to accurately detect sleep-disordered breathing (SDB) in two patients from an outpatient clinic. The first patient suffered from ischemic heart failure and severe central sleep apnea (CSA) and underwent adaptive servoventilation therapy (ASV). The second patient suffered from dilated cardiomyopathy and moderate obstructive sleep apnea (OSA). Pacemaker read-outs did not match polysomnography (PSG) recordings well and overestimated the apnea-hypopnea index. However, ASV therapy-induced SDB improvements were adequately recognized by the apnea scan of the Boston Scientific INVIVE® cardiac resynchronization therapy pacemaker. Detection of obstructive respiratory events using impedance-based technology may underestimate the number of events, as frustrane breathing efforts induce impedance changes without significant airflow. By contrast, in the second case, apnea scan overestimated the number of total events and of obstructive events, perhaps owing to a very sensitive but less specific hypopnea definition and detection within the diagnostic algorithm of the device. These two cases show that a pacemaker apnea scan is able to reflect SDB, but PSG precision is not met by far. The device scan revealed the decline of SDB through ASV therapy for CSA in one patient, but not for OSA in the second case. To achieve reliable monitoring of SDB, further technical developments and clinical studies are necessary.

The Leukocyte Esterase Strip Test has Practical Value for Diagnosing Periprosthetic Joint Infection After Total Knee Arthroplasty: A Multicenter Study.

PubMed

Koh, In J; Han, Seung B; In, Yong; Oh, Kwang J; Lee, Dae H; Kim, Tae K

2017-11-01

Leukocyte esterase (LE) was recently reported to be an accurate marker for diagnosing periprosthetic joint infection (PJI) as defined by the Musculoskeletal Infection Society (MSIS) criteria. However, the diagnostic value of the LE test for PJI after total knee arthroplasty (TKA), the reliability of the subjective visual interpretation of the LE test, and the correlation between the LE test results and the current MSIS criteria remain unclear. This study prospectively enrolled 60 patients undergoing revision TKA for either PJI or aseptic failure. Serological marker, synovial fluid, and histological analyses were performed in all cases. The PJI group comprised 38 cases that met the MSIS criteria and the other 22 cases formed the aseptic group. All the LE tests were interpreted using both visual judgment and automated colorimetric reader. When "++" results were considered to indicate a positive PJI, the sensitivity, specificity, positive and negative predictive value, and diagnostic accuracy were 84, 100, 100, 79, and 90%, respectively. The visual interpretation agreed with the automated colorimetric reader in 90% of cases (Cronbach α = 0.894). The grade of the LE test was strongly correlated with the synovial white blood cell count (ρ = 0.695) and polymorphonuclear leukocyte percentage (ρ = 0.638) and moderately correlated with the serum C-reactive protein and erythrocyte sedimentation rate. The LE test has high diagnostic value for diagnosing PJI after TKA. Subjective visual interpretation of the LE test was reliable and valid for the current battery of PJI diagnostic tests according to the MSIS criteria. Copyright © 2017. Published by Elsevier Inc.

Inter- and intraobserver reliability of the Rockwood classification in acute acromioclavicular joint dislocations.

PubMed

Schneider, M M; Balke, M; Koenen, P; Fröhlich, M; Wafaisade, A; Bouillon, B; Banerjee, M

2016-07-01

The reliability of the Rockwood classification, the gold standard for acute acromioclavicular (AC) joint separations, has not yet been tested. The purpose of this study was to investigate the reliability of visual and measured AC joint lesion grades according to the Rockwood classification. Four investigators (two shoulder specialists and two second-year residents) examined radiographs (bilateral panoramic stress and axial views) in 58 patients and graded the injury according to the Rockwood classification using the following sequence: (1) visual classification of the AC joint lesion, (2) digital measurement of the coracoclavicular distance (CCD) and the horizontal dislocation (HD) with Osirix Dicom Viewer (Pixmeo, Switzerland), (3) classification of the AC joint lesion according to the measurements and (4) repetition of (1) and (2) after repeated anonymization by an independent physician. Visual and measured Rockwood grades as well as the CCD and HD of every patient were documented, and a CC index was calculated (CCD injured/CCD healthy). All records were then used to evaluate intra- and interobserver reliability. The disagreement between visual and measured diagnosis ranged from 6.9 to 27.6 %. Interobserver reliability for visual diagnosis was good (0.72-0.74) and excellent (0.85-0.93) for measured Rockwood grades. Intraobserver reliability was good to excellent (0.67-0.93) for visual diagnosis and excellent for measured diagnosis (0.90-0.97). The correlations between measurements of the axial view varied from 0.68 to 0.98 (good to excellent) for interobserver reliability and from 0.90 to 0.97 (excellent) for intraobserver reliability. Bilateral panoramic stress and axial radiographs are reliable examinations for grading AC joint injuries according to Rockwood's classification. Clinicians of all experience levels can precisely classify AC joint lesions according to the Rockwood classification. We recommend to grade acute ACG lesions by performing a digital measurement instead of a sole visual diagnosis because of the higher intra- and interobserver reliability. Case series, Level IV.

Single-case research design in pediatric psychology: considerations regarding data analysis.

PubMed

Cohen, Lindsey L; Feinstein, Amanda; Masuda, Akihiko; Vowles, Kevin E

2014-03-01

Single-case research allows for an examination of behavior and can demonstrate the functional relation between intervention and outcome in pediatric psychology. This review highlights key assumptions, methodological and design considerations, and options for data analysis. Single-case methodology and guidelines are reviewed with an in-depth focus on visual and statistical analyses. Guidelines allow for the careful evaluation of design quality and visual analysis. A number of statistical techniques have been introduced to supplement visual analysis, but to date, there is no consensus on their recommended use in single-case research design. Single-case methodology is invaluable for advancing pediatric psychology science and practice, and guidelines have been introduced to enhance the consistency, validity, and reliability of these studies. Experts generally agree that visual inspection is the optimal method of analysis in single-case design; however, statistical approaches are becoming increasingly evaluated and used to augment data interpretation.

A comparison of DSM-II and DSM-III in the diagnosis of childhood psychiatric disorders. I. Agreement with expected diagnosis.

PubMed

Cantwell, D P; Russell, A T; Mattison, R; Will, L

1979-10-01

This study was conducted to compare DSM-II and DSM-III in the diagnosis of childhood and adolescent psychiatric disorders. Twenty psychiatrist-raters completed standardized diagnostic questionnaires for 24 actual case histories. This report, the first of four, presents the rater agreement with the "expected diagnosis," ie, the diagnosis that we considered most appropriate for each case. The average rater agreement with the expected diagnosis was less than 50%. It was highest in cases of mental retardation, psychosis, hyperactivity, and conduct disorder. In only five cases did the most common diagnosis of the raters differ from the expected diagnosis. Analyses of these cases and those we selected to present specific diagnostic problems to the raters have produced suggestions to improve the reliability of DSM-III.

A prototype case-based reasoning human assistant for space crew assessment and mission management

NASA Technical Reports Server (NTRS)

Owen, Robert B.; Holland, Albert W.; Wood, Joanna

1993-01-01

We present a prototype human assistant system for space crew assessment and mission management. Our system is based on case episodes from American and Russian space missions and analog environments such as polar stations and undersea habitats. The general domain of small groups in isolated and confined environments represents a near ideal application area for case-based reasoning (CBR) - there are few reliable rules to follow, and most domain knowledge is in the form of cases. We define the problem domain and outline a unique knowledge representation system driven by conflict and communication triggers. The prototype system is able to represent, index, and retrieve case studies of human performance. We index by social, behavioral, and environmental factors. We present the problem domain, our current implementation, our research approach for an operational system, and prototype performance and results.

Photograph-based diagnosis of burns in patients with dark-skin types: the importance of case and assessor characteristics.

PubMed

Boissin, C; Laflamme, L; Wallis, L; Fleming, J; Hasselberg, M

2015-09-01

This study assessed whether photographs of burns on patients with dark-skin types could be used for accurate diagnosing and if the accuracy was affected by physicians' clinical background or case characteristics. 21 South-African cases (Fitzpatrick grades 4-6) of varying complexity were photographed using a camera phone and uploaded on a web-survey. Respondents were asked to assess wound depth (3 categories) and size (in percentage). A sample of 24 burn surgeons and emergency physicians was recruited in South-Africa, USA and Sweden. Measurements of accuracy (using percentage agreement with bedside diagnosis), inter- (n=24), and intra-rater (n=6) reliability (using percentage agreement and kappa) were computed for all cases aggregated and by case characteristic. Overall diagnostic accuracy was 67.5% and 66.0% for burn size and depth, respectively. It was comparable between burn surgeons and emergency physicians and between countries of practice. However, the standard deviations were smaller, showing higher similarities in diagnoses for burn surgeons and South-African clinicians compared to emergency physicians and clinicians from other countries. Case characteristics (child/adult, simple/complex wound, partial/full thickness) affected the results for burn size but not for depth. Inter- and intra-rater reliability for burn depth was 55% and 77%. Size and depth of burns on patients with dark-skin types could be assessed at least as well using photographs as at bedside with 67.5% and 66.0% average accuracy rates. Case characteristics significantly affected the accuracy for burn size, but medical specialty and country of practice seldom did in a statistically significant manner. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

Resimulation of noise: a precision estimator for least square error curve-fitting tested for axial strain time constant imaging

NASA Astrophysics Data System (ADS)

Nair, S. P.; Righetti, R.

2015-05-01

Recent elastography techniques focus on imaging information on properties of materials which can be modeled as viscoelastic or poroelastic. These techniques often require the fitting of temporal strain data, acquired from either a creep or stress-relaxation experiment to a mathematical model using least square error (LSE) parameter estimation. It is known that the strain versus time relationships for tissues undergoing creep compression have a non-linear relationship. In non-linear cases, devising a measure of estimate reliability can be challenging. In this article, we have developed and tested a method to provide non linear LSE parameter estimate reliability: which we called Resimulation of Noise (RoN). RoN provides a measure of reliability by estimating the spread of parameter estimates from a single experiment realization. We have tested RoN specifically for the case of axial strain time constant parameter estimation in poroelastic media. Our tests show that the RoN estimated precision has a linear relationship to the actual precision of the LSE estimator. We have also compared results from the RoN derived measure of reliability against a commonly used reliability measure: the correlation coefficient (CorrCoeff). Our results show that CorrCoeff is a poor measure of estimate reliability for non-linear LSE parameter estimation. While the RoN is specifically tested only for axial strain time constant imaging, a general algorithm is provided for use in all LSE parameter estimation.

A comparative study of the typhidot (Dot-EIA) and Widal tests in blood culture positive cases of typhoid fever.

PubMed

Khoharo, Haji Khan

2011-07-01

Seventy-six blood culture positive typhoid cases and forty-eight controls were studied. The typhidot test was positive in 74 (97.36%) cases, with a sensitivity, specificity and positive predictive value of 96%, 89.5%, and 95%, respectively, compared to the Widal test which was positive in 56 (73.68%) cases with a sensitivity, specificity, and positive predictive value of 72%, 87%, and 87%, respectively (P = 0.001). In the control group, seven (14.5%) cases tested positive for the Widal test and two (4.16%) for the typhidot (P = 0.001), yielding the sensitivity and specificity for the Widal test and the typhidot test of 63% and 83%, and 85% and 97%, respectively. We conclude that the Dot-EIA (enzyme immunoassay; typhidot) is a more sensitive and specific test which is easy to perform and more reliable compared to the Widal test and that it is useful in early therapy.

The tantalum-cased tantalum capacitor

NASA Technical Reports Server (NTRS)

Moynihan, J. D.

1977-01-01

Tantalum-cased tantalum capacitors were tested with regard to temperature stability, capacitance ratio, surge current capabilities, shock, vibration, and thermal shock. They were found to be superior to the conventional wet slug tantalum capacitor cased in silver, since they are more resistant to sulfuric acid. The tantalum-cased tantalum capacitors are widely accepted for use in critical electronic equipment because of their excellent performance and reliability.

Instrument Adaptation in Cross-Cultural Studies of Students' Mathematics-Related Beliefs: Learning from Healthcare Research

ERIC Educational Resources Information Center

Andrews, Paul; Diego-Mantecón, Jose

2015-01-01

Much comparative research into education-related beliefs has exploited questionnaires developed in one culture for use in another. This has been particularly the case in mathematics education, the focus of this paper. In so doing, researchers have tended to assume that translation alone is sufficient to warrant a reliable and valid instrument for…

Primary Trainee Teachers' Attitudes to and Use of Computer and Technology in Mathematics: The Case of Turkey

ERIC Educational Resources Information Center

Dogan, Mustafa

2010-01-01

This study explores Turkish primary mathematics trainee teachers' attitudes to computer and technology. A survey was conducted with a self constructed questionnaire. Piloting, factor and reliability ([alpha] = 0.94) analyses were performed. The final version of the questionnaire has three parts with a total of 48 questions including a Likert type…

Technique for Early Reliability Prediction of Software Components Using Behaviour Models

PubMed Central

Ali, Awad; N. A. Jawawi, Dayang; Adham Isa, Mohd; Imran Babar, Muhammad

2016-01-01

Behaviour models are the most commonly used input for predicting the reliability of a software system at the early design stage. A component behaviour model reveals the structure and behaviour of the component during the execution of system-level functionalities. There are various challenges related to component reliability prediction at the early design stage based on behaviour models. For example, most of the current reliability techniques do not provide fine-grained sequential behaviour models of individual components and fail to consider the loop entry and exit points in the reliability computation. Moreover, some of the current techniques do not tackle the problem of operational data unavailability and the lack of analysis results that can be valuable for software architects at the early design stage. This paper proposes a reliability prediction technique that, pragmatically, synthesizes system behaviour in the form of a state machine, given a set of scenarios and corresponding constraints as input. The state machine is utilized as a base for generating the component-relevant operational data. The state machine is also used as a source for identifying the nodes and edges of a component probabilistic dependency graph (CPDG). Based on the CPDG, a stack-based algorithm is used to compute the reliability. The proposed technique is evaluated by a comparison with existing techniques and the application of sensitivity analysis to a robotic wheelchair system as a case study. The results indicate that the proposed technique is more relevant at the early design stage compared to existing works, and can provide a more realistic and meaningful prediction. PMID:27668748

Wireless Technology Use Case Requirement Analysis for Future Space Applications

NASA Technical Reports Server (NTRS)

Abedi, Ali; Wilkerson, DeLisa

2016-01-01

This report presents various use case scenarios for wireless technology -including radio frequency (RF), optical, and acoustic- and studies requirements and boundary conditions in each scenario. The results of this study can be used to prioritize technology evaluation and development and in the long run help in development of a roadmap for future use of wireless technology. The presented scenarios cover the following application areas: (i) Space Vehicles (manned/unmanned), (ii) Satellites and Payloads, (iii) Surface Explorations, (iv) Ground Systems, and (v) Habitats. The requirement analysis covers two parallel set of conditions. The first set includes the environmental conditions such as temperature, radiation, noise/interference, wireless channel characteristics and accessibility. The second set of requirements are dictated by the application and may include parameters such as latency, throughput (effective data rate), error tolerance, and reliability. This report provides a comprehensive overview of all requirements from both perspectives and details their effects on wireless system reliability and network design. Application area examples are based on 2015 NASA Technology roadmap with specific focus on technology areas: TA 2.4, 3.3, 5.2, 5.5, 6.4, 7.4, and 10.4 sections that might benefit from wireless technology.

Virtual Planning of a Complex Three-Part Bimaxillary Osteotomy

PubMed Central

Anghinoni, Marilena Laura

2017-01-01

In maxillofacial surgery, every patient presents special problems requiring careful evaluation. Conventional methods to study the deformities are still reliable, but the advent of tridimensional (3D) imaging, especially computed tomography (CT) scan and laser scanning of casts, created the opportunity to better understanding the skeletal support and the soft tissue structures. Nowadays, virtual technologies are increasingly employed in maxillofacial surgery and demonstrated precision and reliability. However, in complex surgical procedures, these new technologies are still controversial. Especially in the less frequent cases of three-part maxillary surgery, the experience is limited, and scientific literature cannot give a clear support. This paper presents the case of a young patient affected by a complex long face dentofacial deformity treated by a bimaxillary surgery with three-part segmentation of the maxilla. The operator performed the surgical study completely with a virtual workflow. Pre- and postoperative CT scan and optical scanning of plaster models were collected and compared. Every postoperatory maxillary piece was superimposed with the presurgical one, and the differences were examined in a color-coded map. Only mild differences were found near the osteotomy lines, when the bony surface and the teeth demonstrated an excellent coincidence. PMID:29318057

Acquisition Challenge: The Importance of Incompressibility in Comparing Learning Curve Models

DTIC Science & Technology

2015-10-01

parameters for all four learning mod- els used in the study . The learning rate factor, b, is the slope of the linear regression line, which in this case is...incorporated within the DoD acquisition environment. This study tested three alternative learning models (the Stanford-B model, DeJong’s learning formula...appropriate tools to calculate accurate and reliable predictions. However, conventional learning curve methodology has been in practice since the pre

R&M (Reliability and Maintainability) Program Cost Drivers.

DTIC Science & Technology

1987-05-01

Specific data points used to develop the models (i.e., labor hours mid associated systems and task application characteristics) were obtained from three...study data base used to generate the CER’s em be expanded by adding project data points to the input data given in Appendix 13, adjusting the CER...FRACAS, worst-case/ thermal analyses, stress screening and R-growth. However, the studies did not assign benefits to specific task areas. c. Task

The influence of applying insurance medicine guidelines for depression on disability assessments

PubMed Central

2013-01-01

Background In the current study we report on the effects of an implementation strategy in the form of a training programme on the assessed work limitations of a client with depression by insurance physicians (IPs) participating in a RCT. These assessed work limitations of a client were in the form of scores on the List of Functional Abilities (LFA). Method We conducted a randomised controlled trial (RCT) for IPs in which we compared the intervention of a specially developed training programme with the usual methods of implementation and training currently used. The outcome was the mean sum score and the inter-rater reliability (Intraclass Correlation Coefficient, ICC) of the LFA scores. These LFA scores were scored by the IPs participating in the RCT for the work limitations of the cases presented in different videos, two videos before the training and two after the training of the intervention group. Results At baseline, the intervention group (IG) consisted of 21 IPs and the control group (CG) of 19. For one participant of the IG and for one of the CG the LFAs of the two case reports after training were not available. Before training the sum scores for the first case report did not differ significantly between the groups, while the mean sum score was higher in the IG than in the CG for the second case report. For both case reports after training a higher score was found in the IG than in the CG. The inter-rater reliability measured for the two case reports before training was about the same in the IG and the CG: 0.64 and 0.65, respectively. For the two case reports after training, the ICC was higher in the IG than in the CG: 0.69 and 0.54, respectively. This difference was not significant however. Conclusion It would appear that the implementation of a specially designed training programme on guidelines for depression may lead to greater inter-rater reliability in the assessments by insurance physicians of the work limitations of clients with depression. It is, however, important to note that insurance physicians who receive training may find more work limitations than those who do not. Trial registration Netherlands’ Trial Register NTR1863 PMID:23758690

[Fatal occupational accidents: estimates based on more data sources].

PubMed

Baldasseroni, A; Chellini, E; Zoppi, O; Giovannetti, L

2001-01-01

The data reported by INAIL (Istituto Nazionale Assicurazione Infortuni sul Lavoro) on fatal occupational injuries have always been considered complete and reliable. The authors of this article verified the completeness of this information source crossing it with data bases existing in different registration systems (Regional Mortality Registry of Tuscany--RMR; registers and data of the Operative Units of Prevention, Hygiene and Safety in the Workplace--UOPISLL) for the period between 1992 and 1996. In the five years concerned, a total of 458 cases were reported. These cases could be considered fatal injuries at work without taking into account traffic accidents, which were not included in the present study. The results show that the most complete information source was RMR, reporting 80% of the total data, while INAIL reports only 62.2% of the total cases. On the contrary, the UOPISLL source is the least reliable. Using the capture/recapture method, the estimate of events in the period concerned (1992-1996) amounts to nearly 500 (499.8 LC 475.9-523.7), while the three sources systematically explored for the whole period (INAIL, RMR, UOSPILL) report 458 cases. An additional information source, the daily press, which could be systematically tested only two months for each of the five years, reports 10 additional cases, which were ignored by the 3 other sources, indirectly confirming in this way how reliable the performed estimate was. The main cases among the 157 fatal accidents reported by RMR, but not by INAIL, occurred among farmers (70), most of them already retired, but there were several fatal accidents reported in the construction sector (30). Other categories were included only in the RMR data because, in the period concerned, they were not covered by INAIL insurance (18 cases in the Army and Police, 7 on the railways). The survey that was carried out confirms the essential importance of INAIL data for the surveillance system applied to this phenomenon. This also confirms the need--which has been already stressed in the scientific literature--to combine INAIL's registration system at least with the mortality registries. In this way the knowledge and comprehension of the phenomenon could be integrated and completed especially for marginal work areas, where obligatory insurance may be evaded; and for groups of workers not covered by insurance. The relevance of an integrated system of registration of occupational fatal accidents is discussed.

A cross-validation study of the TGMD-2: The case of an adolescent population.

PubMed

Issartel, Johann; McGrane, Bronagh; Fletcher, Richard; O'Brien, Wesley; Powell, Danielle; Belton, Sarahjane

2017-05-01

This study proposes an extension of a widely used test evaluating fundamental movement skills proficiency to an adolescent population, with a specific emphasis on validity and reliability for this older age group. Cross-sectional observational study. A total of 844 participants (n=456 male, 12.03±0.49) participated in this study. The 12 fundamental movement skills of the TGMD-2 were assessed. Inter-rater reliability was examined to ensure a minimum of 95% consistency between coders. Confirmatory factor analysis was undertaken with a one-factor model (all 12 skills) and two-factor model (6 locomotor skills and 6 object-control skills) as proposed by Ulrich et al. (2000). The model fit was examined using χ 2 , TLI, CFI and RMSEA. Test-retest reliability was carried out with a subsample of 35 participants. The test-retest reliability reached Intraclass Correlation Coefficient of 0.78 (locomotor), 0.76 (object related) and 0.91 (gross motor skill proficiency). The confirmatory factor analysis did not display a good fit for either the one-factor or two-factor model due to a really low contribution of several skills. A reduction in the number of skills to just seven (run, gallop, hop, horizontal jump, bounce, kick and roll) revealed an overall good fit by TLI, CFI and RMSEA measures. The proposed new model offers the possibility of longitudinal studies to track the maturation of fundamental movement skills across the child and adolescent spectrum, while also giving researchers a valid assessment to tool to evaluate adolescent fundamental movement skills proficiency level. Copyright © 2016 Sports Medicine Australia. All rights reserved.

Novel examination for evaluating medical student clinical reasoning: reliability and association with patients seen.

PubMed

Hemmer, Paul A; Dong, Ting; Durning, Steven J; Pangaro, Louis N

2015-04-01

Medical students learn clinical reasoning, in part, through patient care. Although the numbers of patients seen is associated with knowledge examination scores, studies have not demonstrated an association between patient problems and an assessment of clinical reasoning. To examine the reliability of a clinical reasoning examination and investigate whether there was association between internal medicine core clerkship students' performance on this examination and the number of patients they saw with matching problems during their internal medicine clerkship. Students on the core internal medicine clerkship at the Uniformed Services University students log 11 core patient problems based on the Clerkship Directors in Internal Medicine curriculum. On a final clerkship examination (Multistep), students watch a scripted video encounter between physician and patient actors that assesses three sequential steps in clinical reasoning: Step One focuses on history and physical examination; Step Two, students write a problem list after viewing additional clinical findings; Step Three, students complete a prioritized differential diagnosis and treatment plan. Each Multistep examination has three different cases. For graduating classes 2010-2012 (n = 497), we matched the number of patients seen with the problem most represented by the Multistep cases (epigastric pain, generalized edema, monoarticular arthritis, angina, syncope, pleuritic chest pain). We report two-way Pearson correlations between the number of patients students reported with similar problems and the student's percent score on: Step One, Step Two, Step Three, and Overall Test. Multistep reliability: Step 1, 0.6 to 0.8; Step 2, 0.41 to 0.65; Step 3, 0.53 to 0.78; Overall examination (3 cases): 0.74 to 0.83. For three problems, the number of patients seen had small to modest correlations with the Multistep Examination of Analytic Ability total score (r = 0.27 for pleuritic pain, p < 0.05, n = 81 patients; r = 0.14 for epigastric pain, p < 0.05, n = 324 patients; r = 0.19 for generalized edema, p < 0.05, n = 118 patients). DISCUSSION or Although a reliable assessment, student performance on a clinical reasoning examination was weakly associated with the numbers of patients seen with similar problems. This may be as a result of transfer of knowledge between clinical and examination settings, the complexity of clinical reasoning, or the limits of reliability with patient logs and the Multistep. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

KRAS mutation testing in colorectal cancer: comparison of the results obtained using 3 different methods for the analysis of codons G12 and G13.

PubMed

Bihl, Michel P; Hoeller, Sylvia; Andreozzi, Maria Carla; Foerster, Anja; Rufle, Alexander; Tornillo, Luigi; Terracciano, Luigi

2012-03-01

Targeting the epidermal growth factor receptor (EGFR) is a new therapeutic option for patients with metastatic colorectal or lung carcinoma. However, the therapy efficiency highly depends on the KRAS mutation status in the given tumour. Therefore a reliable and secure KRAS mutation testing is crucial. Here we investigated 100 colorectal carcinoma samples with known KRAS mutation status (62 mutated cases and 38 wild type cases) in a comparative manner with three different KRAS mutation testing techniques (Pyrosequencing, Dideoxysequencing and INFINITI) in order to test their reliability and sensitivity. For the large majority of samples (96/100, 96%), the KRAS mutation status obtained by all three methods was the same. Only two cases with clear discrepancies were observed. One case was reported as wild type by the INFINITI method while the two other methods detected a G13C mutation. In the second case the mutation could be detected by the Pyrosequencing and INFINITI method (15% and 15%), while no signal for mutation could be observed with the Dideoxysequencing method. Additional two unclear results were due to a detection of a G12V with the INFINITI method, which was below cut-off when repeated and which was not detectable by the other two methods and very weak signals in a G12V mutated case with the Dideoxy- and Pyroseqencing method compared to the INFINITI method, respectively. In summary all three methods are reliable and robust methods in detecting KRAS mutations. INFINITI, however seems to be slightly more sensitive compared to Dideoxy- and Pyrosequencing.

Smartphone Application for the Analysis of Prosodic Features in Running Speech with a Focus on Bipolar Disorders: System Performance Evaluation and Case Study.

PubMed

Guidi, Andrea; Salvi, Sergio; Ottaviano, Manuel; Gentili, Claudio; Bertschy, Gilles; de Rossi, Danilo; Scilingo, Enzo Pasquale; Vanello, Nicola

2015-11-06

Bipolar disorder is one of the most common mood disorders characterized by large and invalidating mood swings. Several projects focus on the development of decision support systems that monitor and advise patients, as well as clinicians. Voice monitoring and speech signal analysis can be exploited to reach this goal. In this study, an Android application was designed for analyzing running speech using a smartphone device. The application can record audio samples and estimate speech fundamental frequency, F0, and its changes. F0-related features are estimated locally on the smartphone, with some advantages with respect to remote processing approaches in terms of privacy protection and reduced upload costs. The raw features can be sent to a central server and further processed. The quality of the audio recordings, algorithm reliability and performance of the overall system were evaluated in terms of voiced segment detection and features estimation. The results demonstrate that mean F0 from each voiced segment can be reliably estimated, thus describing prosodic features across the speech sample. Instead, features related to F0 variability within each voiced segment performed poorly. A case study performed on a bipolar patient is presented.

A hierarchical Bayesian approach to adaptive vision testing: A case study with the contrast sensitivity function.

PubMed

Gu, Hairong; Kim, Woojae; Hou, Fang; Lesmes, Luis Andres; Pitt, Mark A; Lu, Zhong-Lin; Myung, Jay I

2016-01-01

Measurement efficiency is of concern when a large number of observations are required to obtain reliable estimates for parametric models of vision. The standard entropy-based Bayesian adaptive testing procedures addressed the issue by selecting the most informative stimulus in sequential experimental trials. Noninformative, diffuse priors were commonly used in those tests. Hierarchical adaptive design optimization (HADO; Kim, Pitt, Lu, Steyvers, & Myung, 2014) further improves the efficiency of the standard Bayesian adaptive testing procedures by constructing an informative prior using data from observers who have already participated in the experiment. The present study represents an empirical validation of HADO in estimating the human contrast sensitivity function. The results show that HADO significantly improves the accuracy and precision of parameter estimates, and therefore requires many fewer observations to obtain reliable inference about contrast sensitivity, compared to the method of quick contrast sensitivity function (Lesmes, Lu, Baek, & Albright, 2010), which uses the standard Bayesian procedure. The improvement with HADO was maintained even when the prior was constructed from heterogeneous populations or a relatively small number of observers. These results of this case study support the conclusion that HADO can be used in Bayesian adaptive testing by replacing noninformative, diffuse priors with statistically justified informative priors without introducing unwanted bias.

Smartphone Application for the Analysis of Prosodic Features in Running Speech with a Focus on Bipolar Disorders: System Performance Evaluation and Case Study

PubMed Central

Guidi, Andrea; Salvi, Sergio; Ottaviano, Manuel; Gentili, Claudio; Bertschy, Gilles; de Rossi, Danilo; Scilingo, Enzo Pasquale; Vanello, Nicola

2015-01-01

Bipolar disorder is one of the most common mood disorders characterized by large and invalidating mood swings. Several projects focus on the development of decision support systems that monitor and advise patients, as well as clinicians. Voice monitoring and speech signal analysis can be exploited to reach this goal. In this study, an Android application was designed for analyzing running speech using a smartphone device. The application can record audio samples and estimate speech fundamental frequency, F0, and its changes. F0-related features are estimated locally on the smartphone, with some advantages with respect to remote processing approaches in terms of privacy protection and reduced upload costs. The raw features can be sent to a central server and further processed. The quality of the audio recordings, algorithm reliability and performance of the overall system were evaluated in terms of voiced segment detection and features estimation. The results demonstrate that mean F0 from each voiced segment can be reliably estimated, thus describing prosodic features across the speech sample. Instead, features related to F0 variability within each voiced segment performed poorly. A case study performed on a bipolar patient is presented. PMID:26561811

A hierarchical Bayesian approach to adaptive vision testing: A case study with the contrast sensitivity function

PubMed Central

Gu, Hairong; Kim, Woojae; Hou, Fang; Lesmes, Luis Andres; Pitt, Mark A.; Lu, Zhong-Lin; Myung, Jay I.

2016-01-01

Measurement efficiency is of concern when a large number of observations are required to obtain reliable estimates for parametric models of vision. The standard entropy-based Bayesian adaptive testing procedures addressed the issue by selecting the most informative stimulus in sequential experimental trials. Noninformative, diffuse priors were commonly used in those tests. Hierarchical adaptive design optimization (HADO; Kim, Pitt, Lu, Steyvers, & Myung, 2014) further improves the efficiency of the standard Bayesian adaptive testing procedures by constructing an informative prior using data from observers who have already participated in the experiment. The present study represents an empirical validation of HADO in estimating the human contrast sensitivity function. The results show that HADO significantly improves the accuracy and precision of parameter estimates, and therefore requires many fewer observations to obtain reliable inference about contrast sensitivity, compared to the method of quick contrast sensitivity function (Lesmes, Lu, Baek, & Albright, 2010), which uses the standard Bayesian procedure. The improvement with HADO was maintained even when the prior was constructed from heterogeneous populations or a relatively small number of observers. These results of this case study support the conclusion that HADO can be used in Bayesian adaptive testing by replacing noninformative, diffuse priors with statistically justified informative priors without introducing unwanted bias. PMID:27105061

[SPECIFIC DIAGNOSTIC SIGNIFICANCE OF "RIPPLE SIGN" OF MEDIAL FEMORAL CONDYLE UNDER ARTHROSCOPE IN MEDIAL LONGITUDINAL MENISCAL TEARS].

PubMed

Ren Shiyou; Sun, Limang; Chen, Guofei; Jiang, Changqing; Zhang, Xintao; Zhang Wentao

2015-01-01

To investigate the reliability of the "ripple sign" on the upper surface of the medial femoral condyle in the diagnosis of medial longitudinal meniscal tears under arthroscope. Between June 2013 and June 2014, 56 patients with knee injuries were included. There were 35 males and 21 females with an average age of 22.2 years (range, 12-38 years). The causes of injury were sports in 40 cases, falling in 10 cases, and traffic accident in 6 cases. The injury was located at the left knee in 22 cases and at the right knee in 34 cases. The disease duration was 10-40 days (mean, 20.2 days). Of 56 patients, 15 cases had simple medial meniscal injury; 41 cases had combined injuries, including anterior cruciate ligament injury in 38 cases, posterior cruciate ligament injury in 2 cases, and patellar dislocation in 1 case. The "ripple sign" was observed under arthroscope before operation. Repair of medial meniscal injury and reconstruction of cruciate ligament were performed. The positive "ripple sign" was seen under arthroscope in all patients, who were diagnosed to have longitudinal meniscal tears, including 23 cases of mild "ripple sign" , 28 cases of moderate "ripple sign", and 5 cases of severe "ripple sign". The "ripple sign" on the upper surface of the medial femoral condyle is a reliable diagnostic evidence of medial longitudinal meniscal tears.

Reliability of the one-crossing approximation in describing the Mott transition

NASA Astrophysics Data System (ADS)

Vildosola, V.; Pourovskii, L. V.; Manuel, L. O.; Roura-Bas, P.

2015-12-01

We assess the reliability of the one-crossing approximation (OCA) approach in a quantitative description of the Mott transition in the framework of the dynamical mean field theory (DMFT). The OCA approach has been applied in conjunction with DMFT to a number of heavy-fermion, actinide, transition metal compounds and nanoscale systems. However, several recent studies in the framework of impurity models pointed out serious deficiencies of OCA and raised questions regarding its reliability. Here we consider a single band Hubbard model on the Bethe lattice at finite temperatures and compare the results of OCA to those of a numerically exact quantum Monte Carlo (QMC) method. The temperature-local repulsion U phase diagram for the particle-hole symmetric case obtained by OCA is in good agreement with that of QMC, with the metal-insulator transition captured very well. We find, however, that the insulator to metal transition is shifted to higher values of U and, simultaneously, correlations in the metallic phase are significantly overestimated. This counter-intuitive behaviour is due to simultaneous underestimations of the Kondo scale in the metallic phase and the size of the insulating gap. We trace the underestimation of the insulating gap to that of the second moment of the high-frequency expansion of the impurity spectral density. Calculations of the system away from the particle-hole symmetric case are also presented and discussed.

Electronic Sentinel Surveillance of Influenza-like Illness. Experience from a pilot study in New Zealand.

PubMed

Adnan, Mehnaz; Peterkin, Donald; Lopez, Liza; Mackereth, Graham

2017-02-01

Electronic reporting of Influenza-like illness (eILI) from primary care was implemented and evaluated in three general medical practices in New Zealand during May to September 2015. To measure the uptake of eILI and to identify the system's strength and limitations. Analysis of transactional data from the eILI system; comparative study of influenza-like illness cases reported using manual methods and eILI; questionnaire administered to clinical and operational stakeholders. Over the study period 66% of total ILI cases were reported using eILI. Reporting timeliness improved significantly compared to manual reporting with an average of 24 minutes from submission by the clinician to processing in the national database. Users found the system to be user-friendly. eILI assists clinicians to report ILI cases to public health authorities within a stipulated time period and is associated with faster, more reliable and improved information transfer.

Design criteria monograph for pressurized metal cases

NASA Technical Reports Server (NTRS)

1972-01-01

Organiation and presentation of data pertaining to design of solid propellant rocket engine cases are discussed. Design criteria are presented in form of monograph based on accumulated experience and knowledge. Improvements in reliability, cost effectiveness, and engine efficiency are stressed.

Evaluating the Level of Degree Programmes in Higher Education: The Case of Nursing

ERIC Educational Resources Information Center

Rexwinkel, Trudy; Haenen, Jacques; Pilot, Albert

2013-01-01

The European Quality Assurance system demands that the degree programme level is represented in terms of quantitative outcomes to be valid and reliable. To meet this need the Educational Level Evaluator (ELE) was devised. This conceptually designed procedure with instrumentation aiming to evaluate the level of a degree validly and reliably still…

Reliability Sampling Plans: A Review and Some New Results

ERIC Educational Resources Information Center

Isaic-Maniu, Alexandru; Voda, Viorel Gh.

2009-01-01

In this work we present a large area of aspects related to the problem of sampling inspection in the case of reliability. First we discuss the actual status of this domain, mentioning the newest approaches (from a technical view point) such as HALT and HASS and the statistical perspective. After a brief description of the general procedure in…

Ceramic bearings with bilayer coating in cementless total hip arthroplasty. A safe solution. A retrospective study of one hundred and twenty six cases with more than ten years' follow-up.

PubMed

Ferreira, André; Aslanian, Thierry; Dalin, Thibaud; Picaud, Jean

2017-05-01

Using a ceramic-ceramic bearings, cementless total hip arthroplasty (THA) has provided good clinical results. To ensure longevity a good quality fixation of the implants is mandatory. Different surface treatments had been used, with inconsistent results. We hypothesized that a "bilayer coating" applied to both THA components using validated technology will provide a long-lasting and reliable bone fixation. We studied the survival and bone integration of a continuous, single-surgeon, retrospective series of 126 THA cases (116 patients) with an average follow-up of 12.2 years (minimum 10 years). The THA consisted of cementless implants with a bilayer coating of titanium and hydroxyapatite and used a ceramic-ceramic bearing. With surgical revision for any cause (except infection) as the end point, THA survival was 95.1 % at 13 years. Stem (98.8 %) and cup (98.6 %) survival was similar at 13 years. Bone integration was confirmed in 100 % of implants (Engh-Massin score of 17.42 and ARA score of 5.94). There were no instances of loosening. Revisions were performed because of instability (1.6 %), prosthetic impingement or material-related issues. A bilayer titanium and hydroxyapatite coating provides strong, fast, reliable osseo integration, without deterioration at the interface or release of damaging particles. The good clinical outcomes expected of ceramic bearings were achieved, as were equally reliable stem and cup fixation.

Validity and Reliability of the Filipino Reflux Symptom Index.

PubMed

Lapeña, José Florencio F; Ambrocio, Giancarla Marie C; Carrillo, Ryner Jose D

2017-05-01

This study aimed to establish validity and reliability of the Filipino Reflux Symptom Index (FRSI) and to test it among patients with laryngopharyngeal reflux (LPR) before and after 6 months' trial of rabeprazole. A case-control study was carried out. There were 35 LPR patients and 30 controls who were twice-administered the FRSI and Filipino Voice Handicap Index (FVHI) for test-retest reliability, and videostroboscopy was performed to obtain baseline reflux finding scores (RFSs). Patients took rabeprazole 20 mg twice daily for 6 months. The FRSI and FVHI were readministered a third time, repeat videostroboscopy was performed, and repeat RFS was obtained. Reliability, validity, and internal consistency were computed. A total of 58 participants, 29 patients and controls each, aged 22-65 years completed the study. FVHI 2:1 and FRSI 2:1 significantly correlated with no significant differences between FRSI 2:1. FRSI had good item-total correlations indicating psychometrically sound items. There were significant differences between patients and controls for FRSI scores and mean scores. FRSI 3 scores were significantly lower than FRSI 1 scores, suggesting symptoms improved after treatment. There were no significant differences between RFS 2 and 1. Significant differences between FRSI 3 and 1, but not between FVHI 3 and 1, suggest the FRSI was more sensitive to changes in reflux after 6 months' intervention than the FVHI. The FRSI is a valid and reliable tool for assessing LPR symptoms and may be used for primary care screening among Filipinos. Initial response to a 2-week empirical proton pump inhibitor trial may support an impression of LPR; non-response warrants specialist referral for further investigation. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

[Multi-centre clinical assessment of the Russian language version of the Diagnostic Interview for Psychoses].

PubMed

Smirnova, D A; Petrova, N N; Pavlichenko, A V; Martynikhin, I A; Dorofeikova, M V; Eremkin, V I; Izmailova, O V; Osadshiy, Yu Yu; Romanov, D V; Ubeikon, D A; Fedotov, I A; Sheifer, M S; Shustov, A D; Yashikhina, A A; Clark, M; Badcock, J; Watterreus, A; Morgan, V; Jablensky, A

2018-01-01

The Diagnostic Interview for Psychoses (DIP) was developed to enhance the quality of diagnostic assessment of psychotic disorders. The aim of the study was the adaptation of the Russian language version and evaluation of its validity and reliability. Ninety-eight patients with psychotic disorders (89 video recordings) were assessed by 12 interviewers using the Russian version of DIP at 7 clinical sites (in 6 cities of the Russian Federation). DIP ratings on 32 cases of a randomized case sample were made by 9 interviewers and the inter-rater reliability was compared with the researchers' DIP ratings. Overall pairwise agreement and Cohen's kappa were calculated. Diagnostic validity was evaluated on the basis of comparing the researchers' ratings using the Russian version of DIP with the 'gold standard' ratings of the same 62 clinical cases from the Western Australia Family Study Schizophrenia (WAFSS). The mean duration of the interview was 47±21 minutes. The Kappa statistic demonstrated a significant or almost perfect level of agreement on the majority of DIP items (84.54%) and a significant agreement for the ICD-10 diagnoses generated by the DIP computer diagnostic algorithm (κ=0.68; 95% CI 0.53,0.93). The level of agreement on the researchers' diagnoses was considerably lower (κ=0.31; 95% CI 0.06,0.56). The agreement on affective and positive psychotic symptoms was significantly higher than agreement on negative symptoms (F(2,44)=20.72, p<0.001, η2=0.485). The diagnostic validity of the Russian language version of DIP was confirmed by 73% (45/62) of the Russian DIP diagnoses matching the original WAFSS diagnoses. Among the mismatched diagnoses were 80 cases with a diagnosis of F20 Schizophrenia in the medical documentation compared to the researchers' F20 diagnoses in only 68 patients and in 62 of the DIP computerized diagnostic outputs. The reported level of subjective difficulties experienced when using the DIP was low to moderate. The results of the study confirm the validity and reliability of the Russian version of the DIP for evaluating psychotic disorders. DIP can be recommended for use in education and training, clinical practice and research as an important diagnostic resource.

The SAFE-T assessment tool: derivation and validation of a web-based application for point-of-care evaluation of gastroenterology fellow performance in colonoscopy.

PubMed

Kumar, Navin L; Kugener, Guillaume; Perencevich, Molly L; Saltzman, John R

2018-01-01

Attending assessment is a critical part of endoscopic education for gastroenterology fellows. The aim of this study was to develop and validate a concise assessment tool to evaluate real-time fellow performance in colonoscopy administered via a web-based application. The Skill Assessment in Fellow Endoscopy Training (SAFE-T) tool was derived as a novel 5-question evaluation tool that captures both summative and formative feedback adapted into a web-based application. A prospective study of 15 gastroenterology fellows (5 fellows each from years 1 to 3 of training) was performed using the SAFE-T tool. An independent reviewer evaluated a subset of these procedures and completed the SAFE-T tool and Mayo Colonoscopy Skills Assessment Tool (MCSAT) for reliability testing. Twenty-six faculty completed 350 SAFE-T evaluations of the 15 fellows in the study. The mean SAFE-T overall score (year 1, 2.00; year 2, 3.84; year 3, 4.28) differentiated each sequential fellow year of training (P < .0001). The mean SAFE-T overall score decreased with increasing case complexity score, with straightforward cases compared with average cases (4.07 vs 3.50, P < .0001), and average cases compared with challenging cases (3.50 vs 3.08, P = .0134). In dual-observed procedures, the SAFE-T tool showed excellent inter-rater reliability with a kappa agreement statistic of 0.898 (P < .0001). Correlation of the SAFE-T overall score with the MCSAT overall hands-on and individual motor scores was excellent (each r > 0.90, P < .0001). We developed and validated the SAFE-T assessment tool, a concise and web-based means of assessing real-time gastroenterology fellow performance in colonoscopy. Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Validity and Reliability of Baseline Testing in a Standardized Environment.

PubMed

Higgins, Kathryn L; Caze, Todd; Maerlender, Arthur

2017-08-11

The Immediate Postconcussion Assessment and Cognitive Testing (ImPACT) is a computerized neuropsychological test battery commonly used to determine cognitive recovery from concussion based on comparing post-injury scores to baseline scores. This model is based on the premise that ImPACT baseline test scores are a valid and reliable measure of optimal cognitive function at baseline. Growing evidence suggests that this premise may not be accurate and a large contributor to invalid and unreliable baseline test scores may be the protocol and environment in which baseline tests are administered. This study examined the effects of a standardized environment and administration protocol on the reliability and performance validity of athletes' baseline test scores on ImPACT by comparing scores obtained in two different group-testing settings. Three hundred-sixty one Division 1 cohort-matched collegiate athletes' baseline data were assessed using a variety of indicators of potential performance invalidity; internal reliability was also examined. Thirty-one to thirty-nine percent of the baseline cases had at least one indicator of low performance validity, but there were no significant differences in validity indicators based on environment in which the testing was conducted. Internal consistency reliability scores were in the acceptable to good range, with no significant differences between administration conditions. These results suggest that athletes may be reliably performing at levels lower than their best effort would produce. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Content validity and reliability of test of gross motor development in Chilean children

PubMed Central

Cano-Cappellacci, Marcelo; Leyton, Fernanda Aleitte; Carreño, Joshua Durán

2016-01-01

ABSTRACT OBJECTIVE To validate a Spanish version of the Test of Gross Motor Development (TGMD-2) for the Chilean population. METHODS Descriptive, transversal, non-experimental validity and reliability study. Four translators, three experts and 92 Chilean children, from five to 10 years, students from a primary school in Santiago, Chile, have participated. The Committee of Experts has carried out translation, back-translation and revision processes to determine the translinguistic equivalence and content validity of the test, using the content validity index in 2013. In addition, a pilot implementation was achieved to determine test reliability in Spanish, by using the intraclass correlation coefficient and Bland-Altman method. We evaluated whether the results presented significant differences by replacing the bat with a racket, using T-test. RESULTS We obtained a content validity index higher than 0.80 for language clarity and relevance of the TGMD-2 for children. There were significant differences in the object control subtest when comparing the results with bat and racket. The intraclass correlation coefficient for reliability inter-rater, intra-rater and test-retest reliability was greater than 0.80 in all cases. CONCLUSIONS The TGMD-2 has appropriate content validity to be applied in the Chilean population. The reliability of this test is within the appropriate parameters and its use could be recommended in this population after the establishment of normative data, setting a further precedent for the validation in other Latin American countries. PMID:26815160

The use of self-report questions to examine the prevalence of musculoskeletal problems: a test-retest study.

PubMed

Gill, Tiffany K; Tucker, Graeme R; Avery, Jodie C; Shanahan, E Michael; Menz, Hylton B; Taylor, Anne W; Adams, Robert J; Hill, Catherine L

2016-02-24

Case definition has long been an issue for comparability of results obtained for musculoskeletal pain prevalence, however the test-retest reliability of questions used to determine joint pain prevalence has not been examined. The objective of this study was to determine question reliability and the impact of question wording, ordering and the time between questions on responses. A Computer Assisted Telephone Interviewing (CATI) survey was used to re-administer questions collected as part of a population-based longitudinal cohort study. On two different occasions questions were asked of the same sample of 203 community dwelling respondents (which were initially randomly selected) aged 18 years and over at two time points 14 to 27 days apart (average 15 days). Reliability of the questions was assessed using Cohen's kappa (κ) and intraclass correlation coefficient (ICC) and whether question wording and period effects existed was assessed using a crossover design. The self-reported prevalence of doctor diagnosed arthritis demonstrated excellent reliability (κ = 0.84 and κ = 0.79 for questionnaires 1 and 2 respectively). The reliability of questions relating to musculoskeletal pain and/or stiffness ranged from moderate to excellent for both types of questions, that is, those related to ever having joint pain on most days for at least a month (κ = 0.52 to κ = 0.95) and having pain and/or stiffness on most days for the last month (κ = 0.52 to κ = 0.90). However there was an effect of question wording on the results obtained for hand, foot and back pain and/or stiffness indicating that the area of pain may influence prevalence estimates. Joint pain and stiffness questions are reliable and can be used to determine prevalence. However, question wording and pain area may impact on estimates with issues such as pain perception and effect on activities playing a possible role in the recall of musculoskeletal pain.

Developmental Validation of Short Tandem Repeat Reagent Kit for Forensic DNA Profiling of Canine Biological Materials

PubMed Central

Dayton, Melody; Koskinen, Mikko T; Tom, Bradley K; Mattila, Anna-Maria; Johnston, Eric; Halverson, Joy; Fantin, Dennis; DeNise, Sue; Budowle, Bruce; Smith, David Glenn; Kanthaswamy, Sree

2009-01-01

Aim To develop a reagent kit that enables multiplex polymerase chain reaction (PCR) amplification of 18 short tandem repeats (STR) and the canine sex-determining Zinc Finger marker. Methods Validation studies to determine the robustness and reliability in forensic DNA typing of this multiplex assay included sensitivity testing, reproducibility studies, intra- and inter-locus color balance studies, annealing temperature and cycle number studies, peak height ratio determination, characterization of artifacts such as stutter percentages and dye blobs, mixture analyses, species-specificity, case type samples analyses and population studies. Results The kit robustly amplified domesticated dog samples and consistently generated full 19-locus profiles from as little as 125 pg of dog DNA. In addition, wolf DNA samples could be analyzed with the kit. Conclusion The kit, which produces robust, reliable, and reproducible results, will be made available for the forensic research community after modifications based on this study’s evaluation to comply with the quality standards expected for forensic casework. PMID:19480022

A hypothesis-driven physical examination learning and assessment procedure for medical students: initial validity evidence.

PubMed

Yudkowsky, Rachel; Otaki, Junji; Lowenstein, Tali; Riddle, Janet; Nishigori, Hiroshi; Bordage, Georges

2009-08-01

Diagnostic accuracy is maximised by having clinical signs and diagnostic hypotheses in mind during the physical examination (PE). This diagnostic reasoning approach contrasts with the rote, hypothesis-free screening PE learned by many medical students. A hypothesis-driven PE (HDPE) learning and assessment procedure was developed to provide targeted practice and assessment in anticipating, eliciting and interpreting critical aspects of the PE in the context of diagnostic challenges. This study was designed to obtain initial content validity evidence, performance and reliability estimates, and impact data for the HDPE procedure. Nineteen clinical scenarios were developed, covering 160 PE manoeuvres. A total of 66 Year 3 medical students prepared for and encountered three clinical scenarios during required formative assessments. For each case, students listed anticipated positive PE findings for two plausible diagnoses before examining the patient; examined a standardised patient (SP) simulating one of the diagnoses; received immediate feedback from the SP, and documented their findings and working diagnosis. The same students later encountered some of the scenarios during their Year 4 clinical skills examination. On average, Year 3 students anticipated 65% of the positive findings, correctly performed 88% of the PE manoeuvres and documented 61% of the findings. Year 4 students anticipated and elicited fewer findings overall, but achieved proportionally more discriminating findings, thereby more efficiently achieving a diagnostic accuracy equivalent to that of students in Year 3. Year 4 students performed better on cases on which they had received feedback as Year 3 students. Twelve cases would provide a reliability of 0.80, based on discriminating checklist items only. The HDPE provided medical students with a thoughtful, deliberate approach to learning and assessing PE skills in a valid and reliable manner.

Social tension as precursor of large damaging earthquake: legend or reality?

NASA Astrophysics Data System (ADS)

Molchanov, O.

2008-11-01

Using case study of earthquake (EQ) activity and war conflicts in Caucasus during 1975 2002 time interval and correlation analysis of global distribution of damaging EQs and war-related social tension during 1901 2005 period we conclude:

• There is a statistically reliable increase of social tension several years (or several months in case study) before damaging EQs,
• There is evident decrease of social tension several years after damaging EQs, probably due to society consolidation,
• Preseismic effect is absent for the large EQs in unpopulated areas,
• There is some factual background for legendary belief in Almighty retribution for social abnormal behavior.

Cervical vertebral maturation method and mandibular growth peak: a longitudinal study of diagnostic reliability.

PubMed

Perinetti, Giuseppe; Primozic, Jasmina; Sharma, Bhavna; Cioffi, Iacopo; Contardo, Luca

2018-03-28

The capability of the cervical vertebral maturation (CVM) method in the identification of the mandibular growth peak on an individual basis remains undetermined. The diagnostic reliability of the six-stage CVM method in the identification of the mandibular growth peak was thus investigated. From the files of the Oregon and Burlington Growth Studies (data obtained between early 1950s and middle 1970s), 50 subjects (26 females, 24 males) with at least seven annual lateral cephalograms taken from 9 to 16 years were identified. Cervical vertebral maturation was assessed according to the CVM code staging system, and mandibular growth was defined as annual increments in Co-Gn distance. A diagnostic reliability analysis was carried out to establish the capability of the circumpubertal CVM stages 2, 3, and 4 in the identification of the imminent mandibular growth peak. Variable durations of each of the CVM stages 2, 3, and 4 were seen. The overall diagnostic accuracy values for the CVM stages 2, 3, and 4 were 0.70, 0.76, and 0.77, respectively. These low values appeared to be due to false positive cases. Secular trends in conjunction with the use of a discrete staging system. In most of the Burlington Growth Study sample, the lateral head film at age 15 was missing. None of the CVM stages 2, 3, and 4 reached a satisfactorily diagnostic reliability in the identification of imminent mandibular growth peak.

The Development of DNA Based Methods for the Reliable and Efficient Identification of Nicotiana tabacum in Tobacco and Its Derived Products

PubMed Central

Fan, Wei; Li, Rong; Li, Sifan; Ping, Wenli; Li, Shujun; Naumova, Alexandra; Peelen, Tamara; Yuan, Zheng; Zhang, Dabing

2016-01-01

Reliable methods are needed to detect the presence of tobacco components in tobacco products to effectively control smuggling and classify tariff and excise in tobacco industry to control illegal tobacco trade. In this study, two sensitive and specific DNA based methods, one quantitative real-time PCR (qPCR) assay and the other loop-mediated isothermal amplification (LAMP) assay, were developed for the reliable and efficient detection of the presence of tobacco (Nicotiana tabacum) in various tobacco samples and commodities. Both assays targeted the same sequence of the uridine 5′-monophosphate synthase (UMPS), and their specificities and sensitivities were determined with various plant materials. Both qPCR and LAMP methods were reliable and accurate in the rapid detection of tobacco components in various practical samples, including customs samples, reconstituted tobacco samples, and locally purchased cigarettes, showing high potential for their application in tobacco identification, particularly in the special cases where the morphology or chemical compositions of tobacco have been disrupted. Therefore, combining both methods would facilitate not only the detection of tobacco smuggling control, but also the detection of tariff classification and of excise. PMID:27635142

Statistical Bayesian method for reliability evaluation based on ADT data

NASA Astrophysics Data System (ADS)

Lu, Dawei; Wang, Lizhi; Sun, Yusheng; Wang, Xiaohong

2018-05-01

Accelerated degradation testing (ADT) is frequently conducted in the laboratory to predict the products’ reliability under normal operating conditions. Two kinds of methods, degradation path models and stochastic process models, are utilized to analyze degradation data and the latter one is the most popular method. However, some limitations like imprecise solution process and estimation result of degradation ratio still exist, which may affect the accuracy of the acceleration model and the extrapolation value. Moreover, the conducted solution of this problem, Bayesian method, lose key information when unifying the degradation data. In this paper, a new data processing and parameter inference method based on Bayesian method is proposed to handle degradation data and solve the problems above. First, Wiener process and acceleration model is chosen; Second, the initial values of degradation model and parameters of prior and posterior distribution under each level is calculated with updating and iteration of estimation values; Third, the lifetime and reliability values are estimated on the basis of the estimation parameters; Finally, a case study is provided to demonstrate the validity of the proposed method. The results illustrate that the proposed method is quite effective and accuracy in estimating the lifetime and reliability of a product.

The reliability of a severity rating scale to measure stuttering in an unfamiliar language.

PubMed

Hoffman, Laura; Wilson, Linda; Copley, Anna; Hewat, Sally; Lim, Valerie

2014-06-01

With increasing multiculturalism, speech-language pathologists (SLPs) are likely to work with stuttering clients from linguistic backgrounds that differ from their own. No research to date has estimated SLPs' reliability when measuring severity of stuttering in an unfamiliar language. Therefore, this study was undertaken to estimate the reliability of SLPs' use of a 9-point severity rating (SR) scale, to measure severity of stuttering in a language that was different from their own. Twenty-six Australian SLPs rated 20 speech samples (10 Australian English [AE] and 10 Mandarin) of adults who stutter using a 9-point SR scale on two separate occasions. Judges showed poor agreement when using the scale to measure stuttering in Mandarin samples. Results also indicated that 50% of individual judges were unable to reliably measure the severity of stuttering in AE. The results highlight the need for (a) SLPs to develop intra- and inter-judge agreement when using the 9-point SR scale to measure severity of stuttering in their native language (in this case AE) and in unfamiliar languages; and (b) research into the development and evaluation of practice and/or training packages to assist SLPs to do so.

Portuguese version of the PTSD Checklist-Military Version (PCL-M)-I: Confirmatory Factor Analysis and reliability.

PubMed

Carvalho, Teresa; Cunha, Marina; Pinto-Gouveia, José; Duarte, Joana

2015-03-30

The PTSD Checklist-Military Version (PCL-M) is a brief self-report instrument widely used to assess Post-traumatic Stress Disorder (PTSD) symptomatology in war Veterans, according to DSM-IV. This study sought out to explore the factor structure and reliability of the Portuguese version of the PCL-M. A sample of 660 Portuguese Colonial War Veterans completed the PCL-M. Several Confirmatory Factor Analyses were conducted to test different structures for PCL-M PTSD symptoms. Although the respecified first-order four-factor model based on King et al.'s model showed the best fit to the data, the respecified first and second-order models based on the DSM-IV symptom clusters also presented an acceptable fit. In addition, the PCL-M showed adequate reliability. The Portuguese version of the PCL-M is thus a valid and reliable measure to assess the severity of PTSD symptoms as described in DSM-IV. Its use with Portuguese Colonial War Veterans may ease screening of possible PTSD cases, promote more suitable treatment planning, and enable monitoring of therapeutic outcomes. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Objective structured clinical examination for pharmacy students in Qatar: cultural and contextual barriers to assessment.

PubMed

Wilby, K J; Black, E K; Austin, Z; Mukhalalati, B; Aboulsoud, S; Khalifa, S I

2016-07-10

This study aimed to evaluate the feasibility and psychometric defensibility of implementing a comprehensive objective structured clinical examination (OSCE) on the complete pharmacy programme for pharmacy students in a Middle Eastern context, and to identify facilitators and barriers to implementation within new settings. Eight cases were developed, validated, and had standards set according to a blueprint, and were assessed with graduating pharmacy students. Assessor reliability was evaluated using inter-class coefficients (ICCs). Concurrent validity was evaluated by comparing OSCE results to professional skills course grades. Field notes were maintained to generate recommendations for implementation in other contexts. The examination pass mark was 424 points out of 700 (60.6%). All 23 participants passed. Mean performance was 74.6%. Low to moderate inter-rater reliability was obtained for analytical and global components (average ICC 0.77 and 0.48, respectively). In conclusion, OSCE was feasible in Qatar but context-related validity and reliability concerns must be addressed prior to future iterations in Qatar and elsewhere.

Reliability of medical records in diagnosing inflammatory breast cancer in Egypt.

PubMed

Le, Lynne; Schairer, Catherine; Hablas, Ahmed; Meza, Jane; Watanabe-Galloway, Shinobu; Ramadan, Mohamed; Merajver, Sofia D; Seifeldin, Ibrahim A; Soliman, Amr S

2017-03-16

Inflammatory breast cancer (IBC) is a rare, aggressive breast cancer diagnosed clinically by the presence of diffuse erythema, peau d'orange, and edema that arise quickly in the affected breast. This study evaluated the validity of medical records in Gharbiah, Egypt in identifying clinical signs/symptoms of IBC. For 34 IBC cases enrolled in a case-control study at the Gharbiah Cancer Society and Tanta Cancer Center, Egypt (2009-2010), we compared signs/symptoms of IBC noted in medical records to those recorded on a standardized form at the time of IBC diagnosis by clinicians participating in the case-control study. We calculated the sensitivity and specificity of medical records as compared to the case-control study for recording these signs/symptoms. We also performed McNemar's tests. In the case-control study, 32 (94.1%) IBC cases presented with peau d'orange, 30 (88.2%) with erythema, and 31 (91.2%) with edema. The sensitivities of the medical records as compared to the case-control study were 0.8, 0.5, and 0.2 for peau d'orange, erythema, and edema, respectively. Corresponding specificities were 1.0, 0.5, and 1.0. p values for McNemar's test were <0.05 for all signs. Medical records had data on the extent and duration of signs for at most 27% of cases for which this information was recorded in the case-control study. Twenty-three of the 34 cases (67.6%) had confirmed diagnosis of IBC in their medical records. Medical records lacked information on signs/symptoms of IBC, especially erythema and edema, when compared to the case-control study. Deficient medical records could have implications for diagnosis and treatment of IBC and proper documentation of cases in cancer registries.

German Children’s Use of Word Order and Case Marking to Interpret Simple and Complex Sentences: Testing Differences Between Constructions and Lexical Items

PubMed Central

Brandt, Silke; Lieven, Elena; Tomasello, Michael

2016-01-01

ABSTRACT Children and adults follow cues such as case marking and word order in their assignment of semantic roles in simple transitives (e.g., the dog chased the cat). It has been suggested that the same cues are used for the interpretation of complex sentences, such as transitive relative clauses (RCs) (e.g., that’s the dog that chased the cat) (Bates, Devescovi, & D’Amico, 1999). We used a pointing paradigm to test German-speaking 3-, 4-, and 6-year-old children’s sensitivity to case marking and word order in their interpretation of simple transitives and transitive RCs. In Experiment 1, case marking was ambiguous. The only cue available was word order. In Experiment 2, case was marked on lexical NPs or demonstrative pronouns. In Experiment 3, case was marked on lexical NPs or personal pronouns. Whereas the younger children mainly followed word order, the older children were more likely to base their interpretations on the more reliable case-marking cue. In most cases, children from both age groups were more likely to use these cues in their interpretation of simple transitives than in their interpretation of transitive RCs. Finally, children paid more attention to nominative case when it was marked on first-person personal pronouns than when it was marked on third-person lexical NPs or demonstrative pronouns, such as der Löwe ‘the-NOM lion’ or der ‘he-NOM.’ They were able to successfully integrate this case-marking cue in their sentence processing even when it appeared late in the sentence. We discuss four potential reasons for these differences across development, constructions, and lexical items. (1) Older children are relatively more sensitive to cue reliability. (2) Word order is more reliable in simple transitives than in transitive RCs. (3) The processing of case marking might initially be item-specific. (4) The processing of case marking might depend on its saliency and position in the sentence. PMID:27019652

Case-mix adjustment and enabled reporting of the health care experiences of adults with disabilities.

PubMed

Palsbo, Susan E; Diao, Guoqing; Palsbo, Gregory A; Tang, Liansheng; Rosenberger, William F; Mastal, Margaret F

2010-09-01

To develop activity limitation clusters for case-mix adjustment of health care ratings and as a population profiler, and to develop a cognitively accessible report of statistically reliable quality and access measures comparing the health care experiences of adults with and without disabilities, within and across health delivery organizations. Observational study. Three California Medicaid health care organizations. Adults (N = 1086) of working age enrolled for at least 1 year in Medicaid because of disability. Not applicable. Principal components analysis created 4 clusters of activity limitations that we used to characterize case mix. We identified and calculated 28 quality measures using responses from a proposed enabled version of the Consumer Assessment of Healthcare Providers and Systems (CAHPS) survey. We calculated scores for overall care as the weighted mean of the case-mix adjusted ratings. Disability caused a greater bias on health plan ratings and specialist ratings than did demographic factors. Proxy respondents rated care the same as self-respondents. Telephone and mail administration were equivalent for service reports, but telephone respondents tended to offer more positive global ratings. Plan-level reliability estimates for new composites on shared decision making and advice on healthy living are .79 and .87, respectively. Plan-level reliability estimates for a new composite measure on family planning did not discriminate between health plans because respondents rated all health plans poorly. Approximately 125 respondents per site are necessary to detect group differences. Self-reported activity limitations incorporating standard questions from the American Community Survey can be used to create a disability case-mix index and to construct profiles of a population's activity limitations. The enabled comparative report, which we call the Assessment of Health Plans and Providers by People with Activity Limitations, is more cognitively accessible than typical CAHPS report templates for state Medicaid plans. The CAHPS Medicaid reporting tools may provide misleading ratings of health plan and physician quality by people with disabilities because the mean ratings do not account for systematic biases associated with disability. More testing on larger populations would help to quantify the strength of various reporting biases.

Assessing Variations in Areal Organization for the Intrinsic Brain: From Fingerprints to Reliability

PubMed Central

Xu, Ting; Opitz, Alexander; Craddock, R. Cameron; Wright, Margaret J.; Zuo, Xi-Nian; Milham, Michael P.

2016-01-01

Resting state fMRI (R-fMRI) is a powerful in-vivo tool for examining the functional architecture of the human brain. Recent studies have demonstrated the ability to characterize transitions between functionally distinct cortical areas through the mapping of gradients in intrinsic functional connectivity (iFC) profiles. To date, this novel approach has primarily been applied to iFC profiles averaged across groups of individuals, or in one case, a single individual scanned multiple times. Here, we used a publically available R-fMRI dataset, in which 30 healthy participants were scanned 10 times (10 min per session), to investigate differences in full-brain transition profiles (i.e., gradient maps, edge maps) across individuals, and their reliability. 10-min R-fMRI scans were sufficient to achieve high accuracies in efforts to “fingerprint” individuals based upon full-brain transition profiles. Regarding test–retest reliability, the image-wise intraclass correlation coefficient (ICC) was moderate, and vertex-level ICC varied depending on region; larger durations of data yielded higher reliability scores universally. Initial application of gradient-based methodologies to a recently published dataset obtained from twins suggested inter-individual variation in areal profiles might have genetic and familial origins. Overall, these results illustrate the utility of gradient-based iFC approaches for studying inter-individual variation in brain function. PMID:27600846

Precision, Reliability, and Effect Size of Slope Variance in Latent Growth Curve Models: Implications for Statistical Power Analysis

PubMed Central

Brandmaier, Andreas M.; von Oertzen, Timo; Ghisletta, Paolo; Lindenberger, Ulman; Hertzog, Christopher

2018-01-01

Latent Growth Curve Models (LGCM) have become a standard technique to model change over time. Prediction and explanation of inter-individual differences in change are major goals in lifespan research. The major determinants of statistical power to detect individual differences in change are the magnitude of true inter-individual differences in linear change (LGCM slope variance), design precision, alpha level, and sample size. Here, we show that design precision can be expressed as the inverse of effective error. Effective error is determined by instrument reliability and the temporal arrangement of measurement occasions. However, it also depends on another central LGCM component, the variance of the latent intercept and its covariance with the latent slope. We derive a new reliability index for LGCM slope variance—effective curve reliability (ECR)—by scaling slope variance against effective error. ECR is interpretable as a standardized effect size index. We demonstrate how effective error, ECR, and statistical power for a likelihood ratio test of zero slope variance formally relate to each other and how they function as indices of statistical power. We also provide a computational approach to derive ECR for arbitrary intercept-slope covariance. With practical use cases, we argue for the complementary utility of the proposed indices of a study's sensitivity to detect slope variance when making a priori longitudinal design decisions or communicating study designs. PMID:29755377

Methods for assessing reliability and validity for a measurement tool: a case study and critique using the WHO haemoglobin colour scale.

PubMed

White, Sarah A; van den Broek, Nynke R

2004-05-30

Before introducing a new measurement tool it is necessary to evaluate its performance. Several statistical methods have been developed, or used, to evaluate the reliability and validity of a new assessment method in such circumstances. In this paper we review some commonly used methods. Data from a study that was conducted to evaluate the usefulness of a specific measurement tool (the WHO Colour Scale) is then used to illustrate the application of these methods. The WHO Colour Scale was developed under the auspices of the WHO to provide a simple portable and reliable method of detecting anaemia. This Colour Scale is a discrete interval scale, whereas the actual haemoglobin values it is used to estimate are on a continuous interval scale and can be measured accurately using electrical laboratory equipment. The methods we consider are: linear regression, correlation coefficients, paired t-tests plotting differences against mean values and deriving limits of agreement; kappa and weighted kappa statistics, sensitivity and specificity, an intraclass correlation coefficient and the repeatability coefficient. We note that although the definition and properties of each of these methods is well established inappropriate methods continue to be used in medical literature for assessing reliability and validity, as evidenced in the context of the evaluation of the WHO Colour Scale. Copyright 2004 John Wiley & Sons, Ltd.

Applying the High Reliability Health Care Maturity Model to Assess Hospital Performance: A VA Case Study.

PubMed

Sullivan, Jennifer L; Rivard, Peter E; Shin, Marlena H; Rosen, Amy K

2016-09-01

The lack of a tool for categorizing and differentiating hospitals according to their high reliability organization (HRO)-related characteristics has hindered progress toward implementing and sustaining evidence-based HRO practices. Hospitals would benefit both from an understanding of the organizational characteristics that support HRO practices and from knowledge about the steps necessary to achieve HRO status to reduce the risk of harm and improve outcomes. The High Reliability Health Care Maturity (HRHCM) model, a model for health care organizations' achievement of high reliability with zero patient harm, incorporates three major domains critical for promoting HROs-Leadership, Safety Culture, and Robust Process Improvement ®. A study was conducted to examine the content validity of the HRHCM model and evaluate whether it can differentiate hospitals' maturity levels for each of the model's components. Staff perceptions of patient safety at six US Department of Veterans Affairs (VA) hospitals were examined to determine whether all 14 HRHCM components were present and to characterize each hospital's level of organizational maturity. Twelve of the 14 components from the HRHCM model were detected; two additional characteristics emerged that are present in the HRO literature but not represented in the model-teamwork culture and system-focused tools for learning and improvement. Each hospital's level of organizational maturity could be characterized for 9 of the 14 components. The findings suggest the HRHCM model has good content validity and that there is differentiation between hospitals on model components. Additional research is needed to understand how these components can be used to build the infrastructure necessary for reaching high reliability.

An Adaptation of the Original Fresno Test to Measure Evidence-Based Practice Competence in Pediatric Bedside Nurses.

PubMed

Laibhen-Parkes, Natasha; Kimble, Laura P; Melnyk, Bernadette Mazurek; Sudia, Tanya; Codone, Susan

2018-06-01

Instruments used to assess evidence-based practice (EBP) competence in nurses have been subjective, unreliable, or invalid. The Fresno test was identified as the only instrument to measure all the steps of EBP with supportive reliability and validity data. However, the items and psychometric properties of the original Fresno test are only relevant to measure EBP with medical residents. Therefore, the purpose of this paper is to describe the development of the adapted Fresno test for pediatric nurses, and provide preliminary validity and reliability data for its use with Bachelor of Science in Nursing-prepared pediatric bedside nurses. General adaptations were made to the original instrument's case studies, item content, wording, and format to meet the needs of a pediatric nursing sample. The scoring rubric was also modified to complement changes made to the instrument. Content and face validity, and intrarater reliability of the adapted Fresno test were assessed during a mixed-methods pilot study conducted from October to December 2013 with 29 Bachelor of Science in Nursing-prepared pediatric nurses. Validity data provided evidence for good content and face validity. Intrarater reliability estimates were high. The adapted Fresno test presented here appears to be a valid and reliable assessment of EBP competence in Bachelor of Science in Nursing-prepared pediatric nurses. However, further testing of this instrument is warranted using a larger sample of pediatric nurses in diverse settings. This instrument can be a starting point for evaluating the impact of EBP competence on patient outcomes. © 2018 Sigma Theta Tau International.

Perceiving numbers does not cause automatic shifts of spatial attention.

PubMed

Fattorini, Enrico; Pinto, Mario; Rotondaro, Francesca; Doricchi, Fabrizio

2015-12-01

It is frequently assumed that the brain codes number magnitudes according to an inherent left-to-right spatial organization. In support of this hypothesis it has been reported that in humans, perceiving small numbers induces automatic shifts of attention toward the left side of space whereas perceiving large numbers automatically shifts attention to the right side of space (i.e., Attentional SNARC: Att-SNARC; Fischer, Castel, Dodd, & Pratt, 2003). Nonetheless, the Att-SNARC has been often not replicated and its reliability never tested. To ascertain whether the mere perception of numbers causes shifts of spatial attention or whether number-space interaction takes place at a different stage of cognitive processing, we re-assessed the consistency and reliability of the Att-SNARC and investigated its role in the production of SNARC effects in Parity Judgement (PJ) and Magnitude Comparison (MC) tasks. In a first study in 60 participants, we found no Att-SNARC, despite finding strong PJ- and MC-SNARC effects. No correlation was present between the Att-SNARC and the SNARC. Split-half tests showed no reliability of the Att-SNARC and high reliability of the PJ- and MC-SNARC. In a second study, we re-assessed the Att-SNARC and tested its direct influence on a MC-SNARC task with laterally presented targets. No Att-SNARC and no influence of the Att-SNARC on the MC-SNARC were found. Also in this case, the SNARC was reliable whereas the Att-SNARC task was not. Finally, in a third study we observed a significant Att-SNARC when participants were asked to recall the position occupied on a ruler by the numbers presented in each trial: however the Att-SNARC task was not reliable. These results show that perceiving numbers does not cause automatic shifts of spatial attention and that whenever present, these shifts do not modulate the SNARC. The same results suggest that numbers have no inherent mental left-to-right organization and that, whenever present, this organization can have both response-related and strategically driven memory-related origins. Nonetheless, response-related factors generate more reliable and stable spatial representations of numbers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nanomaterial synthesis and characterization for toxicological studies: TiO2 case study

USGS Publications Warehouse

Valsami-Jones, E.; Berhanu, D.; Dybowska, A.; Misra, S.; Boccaccini, A.R.; Tetley, T.D.; Luoma, S.N.; Plant, J.A.

2008-01-01

In recent years it has become apparent that the novel properties of nanomaterials may predispose them to a hitherto unknown potential for toxicity. A number of recent toxicological studies of nanomaterials exist, but these appear to be fragmented and often contradictory. Such discrepancies may be, at least in part, due to poor description of the nanomaterial or incomplete characterization, including failure to recognise impurities, surface modifications or other important physicochemical aspects of the nanomaterial. Here we make a case for the importance of good quality, well-characterized nanomaterials for future toxicological studies, combined with reliable synthesis protocols, and we present our efforts to generate such materials. The model system for which we present results is TiO2 nanoparticles, currently used in a variety of commercial products. ?? 2008 The Mineralogical Society.

Calculations of reliability predictions for the Apollo spacecraft

NASA Technical Reports Server (NTRS)

Amstadter, B. L.

1966-01-01

A new method of reliability prediction for complex systems is defined. Calculation of both upper and lower bounds are involved, and a procedure for combining the two to yield an approximately true prediction value is presented. Both mission success and crew safety predictions can be calculated, and success probabilities can be obtained for individual mission phases or subsystems. Primary consideration is given to evaluating cases involving zero or one failure per subsystem, and the results of these evaluations are then used for analyzing multiple failure cases. Extensive development is provided for the overall mission success and crew safety equations for both the upper and lower bounds.

The importance of establishing reliability and validity of assessment instruments for mental health problems: An example from Somali children and adolescents living in three refugee camps in Ethiopia

PubMed Central

Hall, Brian J.; Puffer, Eve; Murray, Laura K.; Ismael, Abdulkadir; Bass, Judith K.; Sim, Amanda; Bolton, Paul A.

2014-01-01

Assessing mental health problems cross-culturally for children exposed to war and violence presents a number of unique challenges. One of the most important issues is the lack of validated symptom measures to assess these problems. The present study sought to evaluate the psychometric properties of two measures to assess mental health problems: the Achenbach Youth Self-Report and the Child Posttraumatic Stress Disorder Symptom Scale. We conducted a validity study in three refugee camps in Eastern Ethiopia in the outskirts of Jijiga, the capital of the Somali region. A total of 147 child and caregiver pairs were assessed, and scores obtained were submitted to rigorous psychometric evaluation. Excellent internal consistency reliability was obtained for symptom measures for children and their caregivers. Validation of study instruments based on local case definitions was obtained for the caregivers but not consistently for the children. Sensitivity and specificity of study measures were generally low, indicating that these scales would not perform adequately as screening instruments. Combined test-retest and inter-rater reliability was low for all scales. This study illustrates the need for validation and testing of existing measures cross-culturally. Methodological implications for future cross-cultural research studies in low- and middle-income countries are discussed. PMID:24955147

Reliability of fluorescein dye disappearance test in assessment of adults with nasolacrimal duct obstruction.

PubMed

Kashkouli, Mohsen Bahmani; Mirzajani, Hoora; Jamshidian-Tehrani, Mansooreh; Pakdel, Farzad; Nojomi, Marzieh; Aghaei, Gholam-Hossein

2013-01-01

To evaluate the role of fluorescein dye disappearance test (FDDT) in assessment of adults with primary acquired nasolacrimal duct obstruction (PANDO) and its correlation with age and severity of epiphora. In a prospective, cross-sectional comparative study, FDDT at 2 (2-FDDT), 5 (5-FDDT), and 10 (10-FDDT) minutes were performed in 58 eyes of 58 patients with PANDO (case) and 58 eyes of 58 subjects without epiphora (control) between 2008 and 2010. Exclusion criteria were any disease, trauma, or medications that might have an effect on tear drainage system. Patients with functional or incomplete obstruction and upper lacrimal drainage system obstruction were excluded in the case group. FDDT and severity of epiphora were graded. Case and control groups were matched. 2-FDDT showed a sensitivity of 82.8%, specificity of 91.4%, positive predictive value of 90.6%, and negative predictive value of 84.1%. Sensitivity and negative predictive value decreased to 71.1% and 78.6% in 5-FDDT. 5-FDDT specificity and positive predictive value, however, increased to 94.8% and 93.5%, respectively. There was no statistically significant correlation between severity of epiphora and age with FDDT. FDDT is a simple, reliable, and highly specific test in assessment of adults with PANDO.

Cross-cultural adaptation into Punjabi of the English version of the Hospital Anxiety and Depression Scale.

PubMed

Lane, Deirdre A; Jajoo, Jagdish; Taylor, Rod S; Lip, Gregory Yh; Jolly, Kate

2007-01-26

We wanted to use a Punjabi version of the Hospital Anxiety and Depression Scale (HADS) to enable non-English speaking patients to participate in a clinical trial. The aim of the study was to translate and validate the Hospital Anxiety and Depression Scale into Punjabi. The HADS was translated into Punjabi by a multidisciplinary team, verified against the original version, and administered to 73 bilingual patients attending an outpatient clinic. One sample t-tests and the Bland-Altman plots demonstrated acceptable linguistic agreement between the two versions of the HADS. Spearman's rank-order correlation coefficients (p < 0.0001) demonstrate excellent conceptual agreement between each item and its corresponding subscale score, for both versions. Concordance rates revealed that the Punjabi HADS adequately identified borderline cases of anxiety (80.8%), definite cases of anxiety (91.8%) and depression (91.8%), but was less reliable in identifying borderline cases of depression (65.8%). Cronbach alpha coefficients revealed high levels of internal consistency for both the Punjabi and English versions (0.81 and 0.86 for anxiety and 0.71 and 0.85 for depression, respectively). The Punjabi HADS is an acceptable, reliable and valid measure of anxiety and depression among physically ill Punjabi speaking people in the United Kingdom.

Application of automation and robotics to lunar surface human exploration operations

NASA Technical Reports Server (NTRS)

Woodcock, Gordon R.; Sherwood, Brent; Buddington, Patricia A.; Bares, Leona C.; Folsom, Rolfe; Mah, Robert; Lousma, Jack

1990-01-01

Major results of a study applying automation and robotics to lunar surface base buildup and operations concepts are reported. The study developed a reference base scenario with specific goals, equipment concepts, robot concepts, activity schedules and buildup manifests. It examined crew roles, contingency cases and system reliability, and proposed a set of technologies appropriate and necessary for effective lunar operations. This paper refers readers to four companion papers for quantitative details where appropriate.

A new communication protocol family for a distributed spacecraft control system

NASA Technical Reports Server (NTRS)

Baldi, Andrea; Pace, Marco

1994-01-01

In this paper we describe the concepts behind and architecture of a communication protocol family, which was designed to fulfill the communication requirements of ESOC's new distributed spacecraft control system SCOS 2. A distributed spacecraft control system needs a data delivery subsystem to be used for telemetry (TLM) distribution, telecommand (TLC) dispatch and inter-application communication, characterized by the following properties: reliability, so that any operational workstation is guaranteed to receive the data it needs to accomplish its role; efficiency, so that the telemetry distribution, even for missions with high telemetry rates, does not cause a degradation of the overall control system performance; scalability, so that the network is not the bottleneck both in terms of bandwidth and reconfiguration; flexibility, so that it can be efficiently used in many different situations. The new protocol family which satisfies the above requirements is built on top of widely used communication protocols (UDP and TCP), provides reliable point-to-point and broadcast communication (UDP+) and is implemented in C++. Reliability is achieved using a retransmission mechanism based on a sequence numbering scheme. Such a scheme allows to have cost-effective performances compared to the traditional protocols, because retransmission is only triggered by applications which explicitly need reliability. This flexibility enables applications with different profiles to take advantage of the available protocols, so that the best rate between sped and reliability can be achieved case by case.

Improving the driver-automation interaction: an approach using automation uncertainty.

PubMed

Beller, Johannes; Heesen, Matthias; Vollrath, Mark

2013-12-01

The aim of this study was to evaluate whether communicating automation uncertainty improves the driver-automation interaction. A false system understanding of infallibility may provoke automation misuse and can lead to severe consequences in case of automation failure. The presentation of automation uncertainty may prevent this false system understanding and, as was shown by previous studies, may have numerous benefits. Few studies, however, have clearly shown the potential of communicating uncertainty information in driving. The current study fills this gap. We conducted a driving simulator experiment, varying the presented uncertainty information between participants (no uncertainty information vs. uncertainty information) and the automation reliability (high vs.low) within participants. Participants interacted with a highly automated driving system while engaging in secondary tasks and were required to cooperate with the automation to drive safely. Quantile regressions and multilevel modeling showed that the presentation of uncertainty information increases the time to collision in the case of automation failure. Furthermore, the data indicated improved situation awareness and better knowledge of fallibility for the experimental group. Consequently, the automation with the uncertainty symbol received higher trust ratings and increased acceptance. The presentation of automation uncertaintythrough a symbol improves overall driver-automation cooperation. Most automated systems in driving could benefit from displaying reliability information. This display might improve the acceptance of fallible systems and further enhances driver-automation cooperation.

A cost assessment of reliability requirements for shuttle-recoverable experiments

NASA Technical Reports Server (NTRS)

Campbell, J. W.

1975-01-01

The relaunching of unsuccessful experiments or satellites will become a real option with the advent of the space shuttle. An examination was made of the cost effectiveness of relaxing reliability requirements for experiment hardware by allowing more than one flight of an experiment in the event of its failure. Any desired overall reliability or probability of mission success can be acquired by launching an experiment with less reliability two or more times if necessary. Although this procedure leads to uncertainty in total cost projections, because the number of flights is not known in advance, a considerable cost reduction can sometimes be achieved. In cases where reflight costs are low relative to the experiment's cost, three flights with overall reliability 0.9 can be made for less than half the cost of one flight with a reliability of 0.9. An example typical of shuttle payload cost projections is cited where three low reliability flights would cost less than $50 million and a single high reliability flight would cost over $100 million. The ratio of reflight cost to experiment cost is varied and its effect on the range in total cost is observed. An optimum design reliability selection criterion to minimize expected cost is proposed, and a simple graphical method of determining this reliability is demonstrated.

Effects of DEM source and resolution on WEPP hydrologic and erosion simulation: A case study of two forest watersheds in northern Idaho

Treesearch

J. X. Zhang; J. Q. Wu; K. Chang; W. J. Elliot; S. Dun

2009-01-01

The recent modification of the Water Erosion Prediction Project (WEPP) model has improved its applicability to hydrology and erosion modeling in forest watersheds. To generate reliable topographic and hydrologic inputs for the WEPP model, carefully selecting digital elevation models (DEMs) with appropriate resolution and accuracy is essential because topography is a...

Applying Resource Utilization Groups (RUG-III) in Hong Kong Nursing Homes

ERIC Educational Resources Information Center

Chou, Kee-Lee; Chi, Iris; Leung, Joe C. B.

2008-01-01

Resource Utilization Groups III (RUG-III) is a case-mix system developed in the United States for categorization of nursing home residents and the financing of residential care services. In Hong Kong, RUG-III is based on several board groups of residents. The aim of this study was to examine the reliability and validity of the RUG-III in Hong Kong…

The Integration of Information Operations into Army Operations during Periods of Unstable Peace and Insurgency

DTIC Science & Technology

2011-12-16

broadcasts, but verified by eyewitness accounts spread through word of mouth conduits. See the Dhofari case study. He also explained adversarial...information conduits of the tribes. Word of mouth was to be one the more reliable information...information conduits to its target audiences: notice boards, leaflets, word of mouth , newspapers, radio, and television. Notice boards were placed in