Construction and Validation of a Questionnaire about Heart Failure Patients' Knowledge of Their Disease

PubMed Central

Bonin, Christiani Decker Batista; dos Santos, Rafaella Zulianello; Ghisi, Gabriela Lima de Melo; Vieira, Ariany Marques; Amboni, Ricardo; Benetti, Magnus

2014-01-01

Background The lack of tools to measure heart failure patients' knowledge about their syndrome when participating in rehabilitation programs demonstrates the need for specific recommendations regarding the amount or content of information required. Objectives To develop and validate a questionnaire to assess heart failure patients' knowledge about their syndrome when participating in cardiac rehabilitation programs. Methods The tool was developed based on the Coronary Artery Disease Education Questionnaire and applied to 96 patients with heart failure, with a mean age of 60.22 ± 11.6 years, 64% being men. Reproducibility was obtained via the intraclass correlation coefficient, using the test-retest method. Internal consistency was assessed by use of Cronbach's alpha, and construct validity, by use of exploratory factor analysis. Results The final version of the tool had 19 questions arranged in ten areas of importance for patient education. The proposed questionnaire had a clarity index of 8.94 ± 0.83. The intraclass correlation coefficient was 0.856, and Cronbach's alpha, 0.749. Factor analysis revealed five factors associated with the knowledge areas. Comparing the final scores with the characteristics of the population evidenced that low educational level and low income are significantly associated with low levels of knowledge. Conclusion The instrument has satisfactory clarity and validity indices, and can be used to assess the heart failure patients' knowledge about their syndrome when participating in cardiac rehabilitation programs. PMID:24652054

A systematic review of validated methods for identifying acute respiratory failure using administrative and claims data.

PubMed

Jones, Natalie; Schneider, Gary; Kachroo, Sumesh; Rotella, Philip; Avetisyan, Ruzan; Reynolds, Matthew W

2012-01-01

The Food and Drug Administration's (FDA) Mini-Sentinel pilot program initially aims to conduct active surveillance to refine safety signals that emerge for marketed medical products. A key facet of this surveillance is to develop and understand the validity of algorithms for identifying health outcomes of interest (HOIs) from administrative and claims data. This paper summarizes the process and findings of the algorithm review of acute respiratory failure (ARF). PubMed and Iowa Drug Information Service searches were conducted to identify citations applicable to the anaphylaxis HOI. Level 1 abstract reviews and Level 2 full-text reviews were conducted to find articles using administrative and claims data to identify ARF, including validation estimates of the coding algorithms. Our search revealed a deficiency of literature focusing on ARF algorithms and validation estimates. Only two studies provided codes for ARF, each using related yet different ICD-9 codes (i.e., ICD-9 codes 518.8, "other diseases of lung," and 518.81, "acute respiratory failure"). Neither study provided validation estimates. Research needs to be conducted on designing validation studies to test ARF algorithms and estimating their predictive power, sensitivity, and specificity. Copyright © 2012 John Wiley & Sons, Ltd.

Role of failure-mechanism identification in accelerated testing

NASA Technical Reports Server (NTRS)

Hu, J. M.; Barker, D.; Dasgupta, A.; Arora, A.

1993-01-01

Accelerated life testing techniques provide a short-cut method to investigate the reliability of electronic devices with respect to certain dominant failure mechanisms that occur under normal operating conditions. However, accelerated tests have often been conducted without knowledge of the failure mechanisms and without ensuring that the test accelerated the same mechanism as that observed under normal operating conditions. This paper summarizes common failure mechanisms in electronic devices and packages and investigates possible failure mechanism shifting during accelerated testing.

An Efficient Implementation of Fixed Failure-Rate Ratio Test for GNSS Ambiguity Resolution.

PubMed

Hou, Yanqing; Verhagen, Sandra; Wu, Jie

2016-06-23

Ambiguity Resolution (AR) plays a vital role in precise GNSS positioning. Correctly-fixed integer ambiguities can significantly improve the positioning solution, while incorrectly-fixed integer ambiguities can bring large positioning errors and, therefore, should be avoided. The ratio test is an extensively used test to validate the fixed integer ambiguities. To choose proper critical values of the ratio test, the Fixed Failure-rate Ratio Test (FFRT) has been proposed, which generates critical values according to user-defined tolerable failure rates. This contribution provides easy-to-implement fitting functions to calculate the critical values. With a massive Monte Carlo simulation, the functions for many different tolerable failure rates are provided, which enriches the choices of critical values for users. Moreover, the fitting functions for the fix rate are also provided, which for the first time allows users to evaluate the conditional success rate, i.e., the success rate once the integer candidates are accepted by FFRT. The superiority of FFRT over the traditional ratio test regarding controlling the failure rate and preventing unnecessary false alarms is shown by a simulation and a real data experiment. In the real data experiment with a baseline of 182.7 km, FFRT achieved much higher fix rates (up to 30% higher) and the same level of positioning accuracy from fixed solutions as compared to the traditional critical value.

On Validity Theory and Test Validation

ERIC Educational Resources Information Center

Sireci, Stephen G.

2007-01-01

Lissitz and Samuelsen (2007) propose a new framework for conceptualizing test validity that separates analysis of test properties from analysis of the construct measured. In response, the author of this article reviews fundamental characteristics of test validity, drawing largely from seminal writings as well as from the accepted standards. He…

Embedding Patient Education in Mobile Platform for Patients With Heart Failure: Theory-Based Development and Beta Testing.

PubMed

Athilingam, Ponrathi; Osorio, Richard E; Kaplan, Howard; Oliver, Drew; O'neachtain, Tara; Rogal, Philip J

2016-02-01

Health education is an important component of multidisciplinary disease management of heart failure. The educational information given at the time of discharge after hospitalization or at initial diagnosis is often overwhelming to patients and is often lost or never consulted again. Therefore, the aim of this developmental project was to embed interactive heart failure education in a mobile platform. A patient-centered approach, grounded on several learning theories including Mayer's Cognitive Theory of Multimedia Learning, Sweller's Cognitive Load, Instructional Design Approach, and Problem-Based Learning, was utilized to develop and test the mobile app. Ten heart failure patients, who attended an outpatient heart failure clinic, completed beta testing. A validated self-confidence questionnaire was utilized to assess patients' confidence in using the mobile app. All participants (100%) reported moderate to extreme confidence in using the app, 95% were very likely to use the app, 100% reported the design was easy to navigate, and content on heart failure was appropriate. Having the information accessible on their mobile phone was reported as a positive, like a health coach by all patients. Clinicians and nurses validated the content. Thus, embedding health education in a mobile app is proposed in promoting persistent engagement to improve health outcomes.

Failures in Hybrid Microcircuits During Environmental Testing. History Cases

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2008-01-01

This purpose of this viewgraph presentation is to discuss failures in hermetic hybrids observed at the GSFC PA Lab during environmental stress testing. The cases discussed are: Case I. Substrate metallization failures during Thermal cycling (TC). Case II. Flex lid-induced failure. Case Ill. Hermeticity failures during TC. Case IV. Die metallization cracking during TC. and how many test cycles and parts is necessary? Case V. Wire Bond failures after life test. Case VI. Failures caused by Au/In IMC growth.

Aircraft control surface failure detection and isolation using the OSGLR test. [orthogonal series generalized likelihood ratio

NASA Technical Reports Server (NTRS)

Bonnice, W. F.; Motyka, P.; Wagner, E.; Hall, S. R.

1986-01-01

The performance of the orthogonal series generalized likelihood ratio (OSGLR) test in detecting and isolating commercial aircraft control surface and actuator failures is evaluated. A modification to incorporate age-weighting which significantly reduces the sensitivity of the algorithm to modeling errors is presented. The steady-state implementation of the algorithm based on a single linear model valid for a cruise flight condition is tested using a nonlinear aircraft simulation. A number of off-nominal no-failure flight conditions including maneuvers, nonzero flap deflections, different turbulence levels and steady winds were tested. Based on the no-failure decision functions produced by off-nominal flight conditions, the failure detection and isolation performance at the nominal flight condition was determined. The extension of the algorithm to a wider flight envelope by scheduling on dynamic pressure and flap deflection is examined. Based on this testing, the OSGLR algorithm should be capable of detecting control surface failures that would affect the safe operation of a commercial aircraft. Isolation may be difficult if there are several surfaces which produce similar effects on the aircraft. Extending the algorithm over the entire operating envelope of a commercial aircraft appears feasible.

Failure analysis on false call probe pins of microprocessor test equipment

NASA Astrophysics Data System (ADS)

Tang, L. W.; Ong, N. R.; Mohamad, I. S. B.; Alcain, J. B.; Retnasamy, V.

2017-09-01

A study has been conducted to investigate failure analysis on probe pins of test modules for microprocessor. The `health condition' of the probe pin is determined by the resistance value. A test module of 5V power supplied from Arduino UNO with "Four-wire Ohm measurement" method is implemented in this study to measure the resistance of the probe pins of a microprocessor. The probe pins from a scrapped computer motherboard is used as the test sample in this study. The functionality of the test module was validated with the pre-measurement experiment via VEE Pro software. Lastly, the experimental work have demonstrated that the implemented test module have the capability to identify the probe pin's `health condition' based on the measured resistance value.

Environmental testing to prevent on-orbit TDRS failures

NASA Technical Reports Server (NTRS)

Cutler, Robert M.

1994-01-01

Can improved environmental testing prevent on-orbit component failures such as those experienced in the Tracking and Data Relay Satellite (TDRS) constellation? TDRS communications have been available to user spacecraft continuously for over 11 years, during which the five TDRS's placed in orbit have demonstrated their redundancies and robustness by surviving 26 component failures. Nevertheless, additional environmental testing prior to launch could prevent the occurrence of some types of failures, and could help to maintain communication services. Specific testing challenges involve traveling wave tube assemblies (TWTA's) whose lives may decrease with on-off cycling, and heaters that are subject to thermal cycles. The development of test conditions and procedures should account for known thermal variations. Testing may also have the potential to prevent failures in which components such as diplexers have had their lives dramatically shortened because of particle migration in a weightless environment. Reliability modeling could be used to select additional components that could benefit from special testing, but experience shows that this approach has serious limitations. Through knowledge of on-orbit experience, and with advances in testing, communication satellite programs might avoid the occurrence of some types of failures, and extend future spacecraft longevity beyond the current TDRS design life of ten years. However, determining which components to test, and how must testing to do, remain problematical.

Flight Test of an Adaptive Controller and Simulated Failure/Damage on the NASA NF-15B

NASA Technical Reports Server (NTRS)

Buschbacher, Mark; Maliska, Heather

2006-01-01

The method of flight-testing the Intelligent Flight Control System (IFCS) Second Generation (Gen-2) project on the NASA NF-15B is herein described. The Gen-2 project objective includes flight-testing a dynamic inversion controller augmented by a direct adaptive neural network to demonstrate performance improvements in the presence of simulated failure/damage. The Gen-2 objectives as implemented on the NASA NF-15B created challenges for software design, structural loading limitations, and flight test operations. Simulated failure/damage is introduced by modifying control surface commands, therefore requiring structural loads measurements. Flight-testing began with the validation of a structural loads model. Flight-testing of the Gen-2 controller continued, using test maneuvers designed in a sequenced approach. Success would clear the new controller with respect to dynamic response, simulated failure/damage, and with adaptation on and off. A handling qualities evaluation was conducted on the capability of the Gen-2 controller to restore aircraft response in the presence of a simulated failure/damage. Control room monitoring of loads sensors, flight dynamics, and controller adaptation, in addition to postflight data comparison to the simulation, ensured a safe methodology of buildup testing. Flight-testing continued without major incident to accomplish the project objectives, successfully uncovering strengths and weaknesses of the Gen-2 control approach in flight.

Spacecraft Parachute Recovery System Testing from a Failure Rate Perspective

NASA Technical Reports Server (NTRS)

Stewart, Christine E.

2013-01-01

Spacecraft parachute recovery systems, especially those with a parachute cluster, require testing to identify and reduce failures. This is especially important when the spacecraft in question is human-rated. Due to the recent effort to make spaceflight affordable, the importance of determining a minimum requirement for testing has increased. The number of tests required to achieve a mature design, with a relatively constant failure rate, can be estimated from a review of previous complex spacecraft recovery systems. Examination of the Apollo parachute testing and the Shuttle Solid Rocket Booster recovery chute system operation will clarify at which point in those programs the system reached maturity. This examination will also clarify the risks inherent in not performing a sufficient number of tests prior to operation with humans on-board. When looking at complex parachute systems used in spaceflight landing systems, a pattern begins to emerge regarding the need for a minimum amount of testing required to wring out the failure modes and reduce the failure rate of the parachute system to an acceptable level for human spaceflight. Not only a sufficient number of system level testing, but also the ability to update the design as failure modes are found is required to drive the failure rate of the system down to an acceptable level. In addition, sufficient data and images are necessary to identify incipient failure modes or to identify failure causes when a system failure occurs. In order to demonstrate the need for sufficient system level testing prior to an acceptable failure rate, the Apollo Earth Landing System (ELS) test program and the Shuttle Solid Rocket Booster Recovery System failure history will be examined, as well as some experiences in the Orion Capsule Parachute Assembly System will be noted.

[Failure modes and effects analysis in the prescription, validation and dispensing process].

PubMed

Delgado Silveira, E; Alvarez Díaz, A; Pérez Menéndez-Conde, C; Serna Pérez, J; Rodríguez Sagrado, M A; Bermejo Vicedo, T

2012-01-01

To apply a failure modes and effects analysis to the prescription, validation and dispensing process for hospitalised patients. A work group analysed all of the stages included in the process from prescription to dispensing, identifying the most critical errors and establishing potential failure modes which could produce a mistake. The possible causes, their potential effects, and the existing control systems were analysed to try and stop them from developing. The Hazard Score was calculated, choosing those that were ≥ 8, and a Severity Index = 4 was selected independently of the hazard Score value. Corrective measures and an implementation plan were proposed. A flow diagram that describes the whole process was obtained. A risk analysis was conducted of the chosen critical points, indicating: failure mode, cause, effect, severity, probability, Hazard Score, suggested preventative measure and strategy to achieve so. Failure modes chosen: Prescription on the nurse's form; progress or treatment order (paper); Prescription to incorrect patient; Transcription error by nursing staff and pharmacist; Error preparing the trolley. By applying a failure modes and effects analysis to the prescription, validation and dispensing process, we have been able to identify critical aspects, the stages in which errors may occur and the causes. It has allowed us to analyse the effects on the safety of the process, and establish measures to prevent or reduce them. Copyright © 2010 SEFH. Published by Elsevier Espana. All rights reserved.

Cadaveric study validating in vitro monitoring techniques to measure the failure mechanism of glenoid implants against clinical CT.

PubMed

Junaid, Sarah; Gregory, Thomas; Fetherston, Shirley; Emery, Roger; Amis, Andrew A; Hansen, Ulrich

2018-03-23

Definite glenoid implant loosening is identifiable on radiographs, however, identifying early loosening still eludes clinicians. Methods to monitor glenoid loosening in vitro have not been validated to clinical imaging. This study investigates the correlation between in vitro measures and CT images. Ten cadaveric scapulae were implanted with a pegged glenoid implant and fatigue tested to failure. Each scapulae were cyclically loaded superiorly and CT scanned every 20,000 cycles until failure to monitor progressive radiolucent lines. Superior and inferior rim displacements were also measured. A finite element (FE) model of one scapula was used to analyze the interfacial stresses at the implant/cement and cement/bone interfaces. All ten implants failed inferiorly at the implant-cement interface, two also failed at the cement-bone interface inferiorly, and three showed superior failure. Failure occurred at of 80,966 ± 53,729 (mean ± SD) cycles. CT scans confirmed failure of the fixation, and in most cases, was observed either before or with visual failure. Significant correlations were found between inferior rim displacement, vertical head displacement and failure of the glenoid implant. The FE model showed peak tensile stresses inferiorly and high compressive stresses superiorly, corroborating experimental findings. In vitro monitoring methods correlated to failure progression in clinical CT images possibly indicating its capacity to detect loosening earlier for earlier clinical intervention if needed. Its use in detecting failure non-destructively for implant development and testing is also valuable. The study highlights failure at the implant-cement interface and early signs of failure are identifiable in CT images. © 2018 The Authors. Journal of Orthopaedic Research ® Published by Wiley Periodicals, Inc. on behalf of the Orthopaedic Research Society. J Orthop Res 9999:XX-XX, 2018. © 2018 The Authors. Journal of Orthopaedic Research® Published by

Development and validation of a risk score for hospitalization for heart failure in patients with Type 2 diabetes mellitus.

PubMed

Yang, Xilin; Ma, Ronald C; So, Wing-Yee; Kong, Alice P; Ko, Gary T; Ho, Chun-Shun; Lam, Christopher W; Cockram, Clive S; Tong, Peter C; Chan, Juliana C

2008-04-22

There are no risk scores available for predicting heart failure in Type 2 diabetes mellitus (T2DM). Based on the Hong Kong Diabetes Registry, this study aimed to develop and validate a risk score for predicting heart failure that needs hospitalisation in T2DM. 7067 Hong Kong Chinese diabetes patients without history of heart failure, and without history and clinical evidence of coronary heart disease at baseline were analyzed. The subjects have been followed up for a median period of 5.5 years. Data were randomly and evenly assigned to a training dataset and a test dataset. Sex-stratified Cox proportional hazard regression was used to obtain predictors of HF-related hospitalization in the training dataset. Calibration was assessed using Hosmer-Lemeshow test and discrimination was examined using the area under receiver's operating characteristic curve (aROC) in the test dataset. During the follow-up, 274 patients developed heart failure event/s that needed hospitalisation. Age, body mass index (BMI), spot urinary albumin to creatinine ratio (ACR), HbA1c, blood haemoglobin (Hb) at baseline and coronary heart disease during follow-up were predictors of HF-related hospitalization in the training dataset. HF-related hospitalization risk score = 0.0709 x age (year) + 0.0627 x BMI (kg/m2) + 0.1363 x HbA1c(%) + 0.9915 x Log10(1+ACR) (mg/mmol) - 0.3606 x Blood Hb(g/dL) + 0.8161 x CHD during follow-up (1 if yes). The 5-year probability of heart failure = 1-S0(5)EXP{0.9744 x (Risk Score - 2.3961)}. Where S0(5) = 0.9888 if male and 0.9809 if female. The predicted and observed 5-year probabilities of HF-related hospitalization were similar (p > 0.20) and the adjusted aROC was 0.920 for 5 years of follow-up. The risk score had adequate performance. Further validations in other cohorts of patients with T2DM are needed before clinical use.

Investigation on bending failure to characterize crashworthiness of 6xxx-series aluminium sheet alloys with bending-tension test procedure

NASA Astrophysics Data System (ADS)

Henn, Philipp; Liewald, Mathias; Sindel, Manfred

2018-05-01

As lightweight design as well as crash performance are crucial to future car body design, exact material characterisation is important to use materials at their full potential and reach maximum efficiency. Within the scope of this paper, the potential of newly established bending-tension test procedure to characterise material crashworthiness is investigated. In this test setup for the determination of material failure, a buckling-bending test is coupled with a subsequent tensile test. If prior bending load is critical, tensile strength and elongation in the subsequent tensile test are dramatically reduced. The new test procedure therefore offers an applicable definition of failure as the incapacity of energy consumption in subsequent phases of the crash represents failure of a component. In addition to that, the correlation of loading condition with actual crash scenarios (buckling and free bending) is improved compared to three- point bending test. The potential of newly established bending-tension test procedure to characterise material crashworthiness is investigated in this experimental studys on two aluminium sheet alloys. Experimental results are validated with existing ductility characterisation from edge compression test.

Safety validation test equipment operation

NASA Astrophysics Data System (ADS)

Kurosaki, Tadaaki; Watanabe, Takashi

1992-08-01

An overview of the activities conducted on safety validation test equipment operation for materials used for NASA manned missions is presented. Safety validation tests, such as flammability, odor, offgassing, and so forth were conducted in accordance with NASA-NHB-8060.1C using test subjects common with those used by NASA, and the equipment used were qualified for their functions and performances in accordance with NASDA-CR-99124 'Safety Validation Test Qualification Procedures.' Test procedure systems were established by preparing 'Common Procedures for Safety Validation Test' as well as test procedures for flammability, offgassing, and odor tests. The test operation organization chaired by the General Manager of the Parts and Material Laboratory of NASDA (National Space Development Agency of Japan) was established, and the test leaders and operators in the organization were qualified in accordance with the specified procedures. One-hundred-one tests had been conducted so far by the Parts and Material Laboratory according to the request submitted by the manufacturers through the Space Station Group and the Safety and Product Assurance for Manned Systems Office.

Assessing the Value-Added by the Environmental Testing Process with the Aide of Physics/Engineering of Failure Evaluations

NASA Technical Reports Server (NTRS)

Cornford, S.; Gibbel, M.

1997-01-01

NASA's Code QT Test Effectiveness Program is funding a series of applied research activities focused on utilizing the principles of physics and engineering of failure and those of engineering economics to assess and improve the value-added by the various validation and verification activities to organizations.

Investigation of Spiral Bevel Gear Condition Indicator Validation Via AC-29-2C Using Damage Progression Tests

NASA Technical Reports Server (NTRS)

Dempsey, Paula J.

2014-01-01

This report documents the results of spiral bevel gear rig tests performed under a NASA Space Act Agreement with the Federal Aviation Administration (FAA) to support validation and demonstration of rotorcraft Health and Usage Monitoring Systems (HUMS) for maintenance credits via FAA Advisory Circular (AC) 29-2C, Section MG-15, Airworthiness Approval of Rotorcraft (HUMS) (Ref. 1). The overarching goal of this work was to determine a method to validate condition indicators in the lab that better represent their response to faults in the field. Using existing in-service helicopter HUMS flight data from faulted spiral bevel gears as a "Case Study," to better understand the differences between both systems, and the availability of the NASA Glenn Spiral Bevel Gear Fatigue Rig, a plan was put in place to design, fabricate and test comparable gear sets with comparable failure modes within the constraints of the test rig. The research objectives of the rig tests were to evaluate the capability of detecting gear surface pitting fatigue and other generated failure modes on spiral bevel gear teeth using gear condition indicators currently used in fielded HUMS. Nineteen final design gear sets were tested. Tables were generated for each test, summarizing the failure modes observed on the gear teeth for each test during each inspection interval and color coded based on damage mode per inspection photos. Gear condition indicators (CI) Figure of Merit 4 (FM4), Root Mean Square (RMS), +/- 1 Sideband Index (SI1) and +/- 3 Sideband Index (SI3) were plotted along with rig operational parameters. Statistical tables of the means and standard deviations were calculated within inspection intervals for each CI. As testing progressed, it became clear that certain condition indicators were more sensitive to a specific component and failure mode. These tests were clustered together for further analysis. Maintenance actions during testing were also documented. Correlation coefficients were

The Caregiver Burden Questionnaire for Heart Failure (CBQ-HF): face and content validity

PubMed Central

2013-01-01

Background A new caregiver burden questionnaire for heart failure (CBQ-HF v1.0) was developed based on previously conducted qualitative interviews with HF caregivers and with input from HF clinical experts. Version 1.0 of the CBQ-HF included 41 items measuring the burden associated with caregiving in the following domains: physical, emotional/psychological, social, and impact on caregiver’s life. Following initial development, the next stage was to evaluate caregivers’ understanding of the questionnaire items and their conceptual relevance. Methods To evaluate the face and content validity of the new questionnaire, cognitive interviews were conducted with caregivers of heart failure patients. The cognitive interviews included a “think aloud” exercise as the patient completed the CBQ-HF, followed by more specific probing questions to better understand caregivers’ understanding, interpretation and the relevance of the instructions, items, response scales and recall period. Results Eighteen caregivers of heart failure patients were recruited. The mean age of the caregivers was 50 years (SD = 10.2). Eighty-three percent of caregivers were female and most commonly the patient was either a spouse (44%) or a parent (28%). Among the patients 55% were NYHA Class 2 and 45% were NYHA Class 3 or 4. The caregiver cognitive interviews demonstrated that the CBQ-HF was well understood, relevant and consistently interpreted. From the initial 41 item questionnaire, fifteen items were deleted due to conceptual overlap and/or item redundancy. The final 26-item CBQ-HF (v3.0) uses a 5-point Likert severity scale, assessing 4 domains of physical, emotional/psychological, social and lifestyle burdens using a 4-week recall period. Conclusions The CBQ-HF (v3.0) is a comprehensive and relevant measure of subjective caregiver burden with strong content validity. This study has established that the CBQ-HF (v3.0) has strong face and content validity and should be valuable as an

Orbiter post-tire failure and skid testing results

NASA Technical Reports Server (NTRS)

Daugherty, Robert H.; Stubbs, Sandy M.

1989-01-01

An investigation was conducted at the NASA Langley Research Center's Aircraft Landing Dynamics Facility (ALDF) to define the post-tire failure drag characteristics of the Space Shuttle Orbiter main tire and wheel assembly. Skid tests on various materials were also conducted to define their friction and wear rate characteristics under higher speed and bearing pressures than any previous tests. The skid tests were conducted to support a feasibility study of adding a skid to the orbiter strut between the main tires to protect an intact tire from failure due to overload should one of the tires fail. Roll-on-rim tests were conducted to define the ability of a standard and a modified orbiter main wheel to roll without a tire. Results of the investigation are combined into a generic model of strut drag versus time under failure conditions for inclusion into rollout simulators used to train the shuttle astronauts.

Rigging Test Bed Development for Validation of Multi-Stage Decelerator Extractions

NASA Technical Reports Server (NTRS)

Kenig, Sivan J.; Gallon, John C.; Adams, Douglas S.; Rivellini, Tommaso P.

2013-01-01

The Low Density Supersonic Decelerator project is developing new decelerator systems for Mars entry which would include testing with a Supersonic Flight Dynamics Test Vehicle. One of the decelerator systems being developed is a large supersonic ringsail parachute. Due to the configuration of the vehicle it is not possible to deploy the parachute with a mortar which would be the preferred method for a spacecraft in a supersonic flow. Alternatively, a multi-stage extraction process using a ballute as a pilot is being developed for the test vehicle. The Rigging Test Bed is a test venue being constructed to perform verification and validation of this extraction process. The test bed consists of a long pneumatic piston device capable of providing a constant force simulating the ballute drag force during the extraction events. The extraction tests will take place both inside a high-bay for frequent tests of individual extraction stages and outdoors using a mobile hydraulic crane for complete deployment tests from initial pack pull out to canopy extraction. These tests will measure line tensions and use photogrammetry to track motion of the elements involved. The resulting data will be used to verify packing and rigging as well, as validate models and identify potential failure modes in order to finalize the design of the extraction system.

On the Validity of Useless Tests

ERIC Educational Resources Information Center

Sireci, Stephen G.

2016-01-01

A misconception exists that validity may refer only to the "interpretation" of test scores and not to the "uses" of those scores. The development and evolution of validity theory illustrate test score interpretation was a primary focus in the earliest days of modern testing, and that validating interpretations derived from test…

Validity evidence based on test content.

PubMed

Sireci, Stephen; Faulkner-Bond, Molly

2014-01-01

Validity evidence based on test content is one of the five forms of validity evidence stipulated in the Standards for Educational and Psychological Testing developed by the American Educational Research Association, American Psychological Association, and National Council on Measurement in Education. In this paper, we describe the logic and theory underlying such evidence and describe traditional and modern methods for gathering and analyzing content validity data. A comprehensive review of the literature and of the aforementioned Standards is presented. For educational tests and other assessments targeting knowledge and skill possessed by examinees, validity evidence based on test content is necessary for building a validity argument to support the use of a test for a particular purpose. By following the methods described in this article, practitioners have a wide arsenal of tools available for determining how well the content of an assessment is congruent with and appropriate for the specific testing purposes.

Railcar Roller Bearing Failure Progression Tests

DOT National Transportation Integrated Search

1982-04-01

This report describes the laboratory endurance test of six railcar roller bearings that had previously suffered physical damage or were otherwise degraded as a result of actual railroad service. Two different onboard impending bearing failure sensors...

Taming Test Anxiety: The Activation of Failure-Related Concepts Enhances Cognitive Test Performance of Test-Anxious Students

ERIC Educational Resources Information Center

Tempel, Tobias; Neumann, Roland

2016-01-01

We investigated processes underlying performance decrements of highly test-anxious persons. Three experiments contrasted conditions that differed in the degree of activation of concepts related to failure. Participants memorized a list of words either containing words related to failure or containing no words related to failure in Experiment 1. In…

Flight Testing an Iced Business Jet for Flight Simulation Model Validation

NASA Technical Reports Server (NTRS)

Ratvasky, Thomas P.; Barnhart, Billy P.; Lee, Sam; Cooper, Jon

2007-01-01

A flight test of a business jet aircraft with various ice accretions was performed to obtain data to validate flight simulation models developed through wind tunnel tests. Three types of ice accretions were tested: pre-activation roughness, runback shapes that form downstream of the thermal wing ice protection system, and a wing ice protection system failure shape. The high fidelity flight simulation models of this business jet aircraft were validated using a software tool called "Overdrive." Through comparisons of flight-extracted aerodynamic forces and moments to simulation-predicted forces and moments, the simulation models were successfully validated. Only minor adjustments in the simulation database were required to obtain adequate match, signifying the process used to develop the simulation models was successful. The simulation models were implemented in the NASA Ice Contamination Effects Flight Training Device (ICEFTD) to enable company pilots to evaluate flight characteristics of the simulation models. By and large, the pilots confirmed good similarities in the flight characteristics when compared to the real airplane. However, pilots noted pitch up tendencies at stall with the flaps extended that were not representative of the airplane and identified some differences in pilot forces. The elevator hinge moment model and implementation of the control forces on the ICEFTD were identified as a driver in the pitch ups and control force issues, and will be an area for future work.

On-clip high frequency reliability and failure test structures

DOEpatents

Snyder, Eric S.; Campbell, David V.

1997-01-01

Self-stressing test structures for realistic high frequency reliability characterizations. An on-chip high frequency oscillator, controlled by DC signals from off-chip, provides a range of high frequency pulses to test structures. The test structures provide information with regard to a variety of reliability failure mechanisms, including hot-carriers, electromigration, and oxide breakdown. The system is normally integrated at the wafer level to predict the failure mechanisms of the production integrated circuits on the same wafer.

On-clip high frequency reliability and failure test structures

DOEpatents

Snyder, E.S.; Campbell, D.V.

1997-04-29

Self-stressing test structures for realistic high frequency reliability characterizations. An on-chip high frequency oscillator, controlled by DC signals from off-chip, provides a range of high frequency pulses to test structures. The test structures provide information with regard to a variety of reliability failure mechanisms, including hot-carriers, electromigration, and oxide breakdown. The system is normally integrated at the wafer level to predict the failure mechanisms of the production integrated circuits on the same wafer. 22 figs.

Validation of alternative methods for toxicity testing.

PubMed Central

Bruner, L H; Carr, G J; Curren, R D; Chamberlain, M

1998-01-01

Before nonanimal toxicity tests may be officially accepted by regulatory agencies, it is generally agreed that the validity of the new methods must be demonstrated in an independent, scientifically sound validation program. Validation has been defined as the demonstration of the reliability and relevance of a test method for a particular purpose. This paper provides a brief review of the development of the theoretical aspects of the validation process and updates current thinking about objectively testing the performance of an alternative method in a validation study. Validation of alternative methods for eye irritation testing is a specific example illustrating important concepts. Although discussion focuses on the validation of alternative methods intended to replace current in vivo toxicity tests, the procedures can be used to assess the performance of alternative methods intended for other uses. Images Figure 1 PMID:9599695

Validation of a Videoconferenced Speaking Test

ERIC Educational Resources Information Center

Kim, Jungtae; Craig, Daniel A.

2012-01-01

Videoconferencing offers new opportunities for language testers to assess speaking ability in low-stakes diagnostic tests. To be considered a trusted testing tool in language testing, a test should be examined employing appropriate validation processes [Chapelle, C.A., Jamieson, J., & Hegelheimer, V. (2003). "Validation of a web-based ESL…

Failure Modes in Capacitors When Tested Under a Time-Varying Stress

NASA Technical Reports Server (NTRS)

Liu, David (Donhang)

2011-01-01

Steady step surge testing (SSST) is widely applied to screen out potential power-on failures in solid tantalum capacitors. The test simulates the power supply's on and off characteristics. Power-on failure has been the prevalent failure mechanism for solid tantalum capacitors for decoupling applications. On the other hand, the SSST can also be reviewed as an electrically destructive test under a time-varying stress. It consists of rapidly charging the capacitor with incremental voltage increases, through a low resistance in series, until the capacitor under test is electrically shorted. Highly accelerated life testing (HALT) is usually a time-efficient method for determining the failure mechanism in capacitors; however, a destructive test under a time-varying stress like SSST is even more effective. It normally takes days to complete a HALT test, but it only takes minutes for a time-varying stress test to produce failures. The advantage of incorporating specific time-varying stress into a statistical model is significant in providing an alternative life test method for quickly revealing the failure modes in capacitors. In this paper, a time-varying stress has been incorporated into the Weibull model to characterize the failure modes. The SSST circuit and transient conditions to correctly test the capacitors is discussed. Finally, the SSST was applied for testing polymer aluminum capacitors (PA capacitors), Ta capacitors, and multi-layer ceramic capacitors with both precious metal electrode (PME) and base-metal-electrodes (BME). It appears that testing results are directly associated to the dielectric layer breakdown in PA and Ta capacitors and are independent on the capacitor values, the way the capacitors being built, and the manufactures. The testing results also reveal that ceramic capacitors exhibit breakdown voltages more than 20 times the rated voltage, and the breakdown voltages are inverse proportional to the dielectric layer thickness. The possibility of

Analysis for the Progressive Failure Response of Textile Composite Fuselage Frames

NASA Technical Reports Server (NTRS)

Johnson, Eric R.; Boitnott, Richard L. (Technical Monitor)

2002-01-01

A part of aviation accident mitigation is a crash worthy airframe structure, and an important measure of merit for a crash worthy structure is the amount of kinetic energy that can be absorbed in the crush of the structure. Prediction of the energy absorbed from finite element analyses requires modeling the progressive failure sequence. Progressive failure modes may include material degradation, fracture and crack growth, and buckling and collapse. The design of crash worthy airframe components will benefit from progressive failure analyses that have been validated by tests. The subject of this research is the development of a progressive failure analysis for textile composite. circumferential fuselage frames subjected to a quasi-static, crash-type load. The test data for these frames are reported, and these data, along with stub column test data, are to be used to develop and to validate methods for the progressive failure response.

10 CFR 26.131 - Cutoff levels for validity screening and initial validity tests.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Cutoff levels for validity screening and initial validity tests. 26.131 Section 26.131 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Licensee Testing Facilities § 26.131 Cutoff levels for validity screening and initial validity tests. (a) Each...

10 CFR 26.131 - Cutoff levels for validity screening and initial validity tests.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Cutoff levels for validity screening and initial validity tests. 26.131 Section 26.131 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Licensee Testing Facilities § 26.131 Cutoff levels for validity screening and initial validity tests. (a) Each...

Evaluation of the Effect of the Volume Throughput and Maximum Flux of Low-Surface-Tension Fluids on Bacterial Penetration of 0.2 Micron-Rated Filters during Process-Specific Filter Validation Testing.

PubMed

Folmsbee, Martha

2015-01-01

Approximately 97% of filter validation tests result in the demonstration of absolute retention of the test bacteria, and thus sterile filter validation failure is rare. However, while Brevundimonas diminuta (B. diminuta) penetration of sterilizing-grade filters is rarely detected, the observation that some fluids (such as vaccines and liposomal fluids) may lead to an increased incidence of bacterial penetration of sterilizing-grade filters by B. diminuta has been reported. The goal of the following analysis was to identify important drivers of filter validation failure in these rare cases. The identification of these drivers will hopefully serve the purpose of assisting in the design of commercial sterile filtration processes with a low risk of filter validation failure for vaccine, liposomal, and related fluids. Filter validation data for low-surface-tension fluids was collected and evaluated with regard to the effect of bacterial load (CFU/cm(2)), bacterial load rate (CFU/min/cm(2)), volume throughput (mL/cm(2)), and maximum filter flux (mL/min/cm(2)) on bacterial penetration. The data set (∼1162 individual filtrations) included all instances of process-specific filter validation failures performed at Pall Corporation, including those using other filter media, but did not include all successful retentive filter validation bacterial challenges. It was neither practical nor necessary to include all filter validation successes worldwide (Pall Corporation) to achieve the goals of this analysis. The percentage of failed filtration events for the selected total master data set was 27% (310/1162). Because it is heavily weighted with penetration events, this percentage is considerably higher than the actual rate of failed filter validations, but, as such, facilitated a close examination of the conditions that lead to filter validation failure. In agreement with our previous reports, two of the significant drivers of bacterial penetration identified were the total

Validation of bending tests by nanoindentation for micro-contact analysis of MEMS switches

NASA Astrophysics Data System (ADS)

Broue, Adrien; Fourcade, Thibaut; Dhennin, Jérémie; Courtade, Frédéric; Charvet, Pierre–Louis; Pons, Patrick; Lafontan, Xavier; Plana, Robert

2010-08-01

Research on contact characterization for microelectromechanical system (MEMS) switches has been driven by the necessity to reach a high-reliability level for micro-switch applications. One of the main failures observed during cycling of the devices is the increase of the electrical contact resistance. The key issue is the electromechanical behaviour of the materials used at the contact interface where the current flows through. Metal contact switches have a large and complex set of failure mechanisms according to the current level. This paper demonstrates the validity of a new methodology using a commercial nanoindenter coupled with electrical measurements on test vehicles specially designed to investigate the micro-scale contact physics. Dedicated validation tests and modelling are performed to assess the introduced methodology by analyzing the gold contact interface with 5 µm2 square bumps at various current levels. Contact temperature rise is measured, which affects the mechanical properties of the contact materials and modifies the contact topology. In addition, the data provide a better understanding of micro-contact behaviour related to the impact of current at low- to medium-power levels. This article was originally submitted for the special section 'Selected papers from the 20th Micromechanics Europe Workshop (MME 09) (Toulouse, France, 20-22 September 2009)', Journal of Micromechanics and Microengineering, volume 20, issue 6.

Testing and validating environmental models

USGS Publications Warehouse

Kirchner, J.W.; Hooper, R.P.; Kendall, C.; Neal, C.; Leavesley, G.

1996-01-01

Generally accepted standards for testing and validating ecosystem models would benefit both modellers and model users. Universally applicable test procedures are difficult to prescribe, given the diversity of modelling approaches and the many uses for models. However, the generally accepted scientific principles of documentation and disclosure provide a useful framework for devising general standards for model evaluation. Adequately documenting model tests requires explicit performance criteria, and explicit benchmarks against which model performance is compared. A model's validity, reliability, and accuracy can be most meaningfully judged by explicit comparison against the available alternatives. In contrast, current practice is often characterized by vague, subjective claims that model predictions show 'acceptable' agreement with data; such claims provide little basis for choosing among alternative models. Strict model tests (those that invalid models are unlikely to pass) are the only ones capable of convincing rational skeptics that a model is probably valid. However, 'false positive' rates as low as 10% can substantially erode the power of validation tests, making them insufficiently strict to convince rational skeptics. Validation tests are often undermined by excessive parameter calibration and overuse of ad hoc model features. Tests are often also divorced from the conditions under which a model will be used, particularly when it is designed to forecast beyond the range of historical experience. In such situations, data from laboratory and field manipulation experiments can provide particularly effective tests, because one can create experimental conditions quite different from historical data, and because experimental data can provide a more precisely defined 'target' for the model to hit. We present a simple demonstration showing that the two most common methods for comparing model predictions to environmental time series (plotting model time series

Failure Modes in Capacitors When Tested Under a Time-Varying Stress

NASA Technical Reports Server (NTRS)

Liu, David (Donhang)

2011-01-01

Power-on failure has been the prevalent failure mechanism for solid tantalum capacitors in decoupling applications. A surge step stress test (SSST) has been previously applied to identify the critical stress level of a capacitor batch to give some predictability to the power-on failure mechanism [1]. But SSST can also be viewed as an electrically destructive test under a time-varying stress (voltage). It consists of rapidly charging the capacitor with incremental voltage increases, through a low resistance in series, until the capacitor under test is electrically shorted. When the reliability of capacitors is evaluated, a highly accelerated life test (HALT) is usually adopted since it is a time-efficient method of determining the failure mechanism; however, a destructive test under a time-varying stress such as SSST is even more time efficient. It usually takes days or weeks to complete a HALT test, but it only takes minutes for a time-varying stress test to produce failures. The advantage of incorporating a specific time-varying stress profile into a statistical model is significant in providing an alternative life test method for quickly revealing the failure mechanism in capacitors. In this paper, a time-varying stress that mimics a typical SSST has been incorporated into the Weibull model to characterize the failure mechanism in different types of capacitors. The SSST circuit and transient conditions for correctly surge testing capacitors are discussed. Finally, the SSST was applied for testing Ta capacitors, polymer aluminum capacitors (PA capacitors), and multi-layer ceramic (MLC) capacitors with both precious metal electrodes (PME) and base metal electrodes (BME). The test results are found to be directly associated with the dielectric layer breakdown in Ta and PA capacitors and are independent of the capacitor values, the way the capacitors were built, and the capacitors manufacturers. The test results also show that MLC capacitors exhibit surge breakdown

The prone bridge test: Performance, validity, and reliability among older and younger adults.

PubMed

Bohannon, Richard W; Steffl, Michal; Glenney, Susan S; Green, Michelle; Cashwell, Leah; Prajerova, Kveta; Bunn, Jennifer

2018-04-01

The prone bridge maneuver, or plank, has been viewed as a potential alternative to curl-ups for assessing trunk muscle performance. The purpose of this study was to assess prone bridge test performance, validity, and reliability among younger and older adults. Sixty younger (20-35 years old) and 60 older (60-79 years old) participants completed this study. Groups were evenly divided by sex. Participants completed surveys regarding physical activity and abdominal exercise participation. Height, weight, body mass index (BMI), and waist circumference were measured. On two occasions, 5-9 days apart, participants held a prone bridge until volitional exhaustion or until repeated technique failure. Validity was examined using data from the first session: convergent validity by calculating correlations between survey responses, anthropometrics, and prone bridge time, known groups validity by using an ANOVA comparing bridge times of younger and older adults and of men and women. Test-retest reliability was examined by using a paired t-test to compare prone bridge times for Session1 and Session 2. Furthermore, an intraclass correlation coefficient (ICC) was used to characterize relative reliability and minimal detectable change (MDC 95% ) was used to describe absolute reliability. The mean prone bridge time was 145.3 ± 71.5 s, and was positively correlated with physical activity participation (p ≤ 0.001) and negatively correlated with BMI and waist circumference (p ≤ 0.003). Younger participants had significantly longer plank times than older participants (p = 0.003). The ICC between testing sessions was 0.915. The prone bridge test is a valid and reliable measure for evaluating abdominal performance in both younger and older adults. Copyright © 2017 Elsevier Ltd. All rights reserved.

Analysis for the Progressive Failure Response of Textile Composite Fuselage Frames

NASA Technical Reports Server (NTRS)

Johnson, Eric R.; Boitnott, Richard L. (Technical Monitor)

2002-01-01

A part of aviation accident mitigation is a crashworthy airframe structure, and an important measure of merit for a crashworthy structure is the amount of kinetic energy that can be absorbed in the crush of the structure. Prediction of the energy absorbed from finite element analyses requires modeling the progressive failure sequence. Progressive failure modes may include material degradation, fracture and crack growth, and buckling and collapse. The design of crashworthy airframe components will benefit from progressive failure analyses that have been validated by tests. The subject of this research is the development of a progressive failure analysis for a textile composite, circumferential fuselage frame subjected to a quasi-static, crash-type load. The test data for the frame are reported, and these data are used to develop and to validate methods for the progressive failure response.

Moving beyond the Failure of Test-Based Accountability

ERIC Educational Resources Information Center

Koretz, Daniel

2018-01-01

In "The Testing Charade: Pretending to Make Schools Better", the author's new book from which this article is drawn, the failures of test-based accountability are documented and some of the most egregious misuses and outright abuses of testing are described, along with some of the most serious negative effects. Neither good intentions…

Space Shuttle Solid Rocket Booster Decelerator Subsystem Drop Test 3 - Anatomy of a failure

NASA Technical Reports Server (NTRS)

Runkle, R. E.; Woodis, W. R.

1979-01-01

A test failure dramatically points out a design weakness or the limits of the material in the test article. In a low budget test program, with a very limited number of tests, a test failure sparks supreme efforts to investigate, analyze, and/or explain the anomaly and to improve the design such that the failure will not recur. The third air drop of the Space Shuttle Solid Rocket Booster Recovery System experienced such a dramatic failure. On air drop 3, the 54-ft drogue parachute was totally destroyed 0.7 sec after deployment. The parachute failure investigation, based on analysis of drop test data and supporting ground element test results is presented. Drogue design modifications are also discussed.

Development and Validation of a Lifecycle-based Prognostics Architecture with Test Bed Validation

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

Hines, J. Wesley; Upadhyaya, Belle; Sharp, Michael

On-line monitoring and tracking of nuclear plant system and component degradation is being investigated as a method for improving the safety, reliability, and maintainability of aging nuclear power plants. Accurate prediction of the current degradation state of system components and structures is important for accurate estimates of their remaining useful life (RUL). The correct quantification and propagation of both the measurement uncertainty and model uncertainty is necessary for quantifying the uncertainty of the RUL prediction. This research project developed and validated methods to perform RUL estimation throughout the lifecycle of plant components. Prognostic methods should seamlessly operate from beginning ofmore » component life (BOL) to end of component life (EOL). We term this "Lifecycle Prognostics." When a component is put into use, the only information available may be past failure times of similar components used in similar conditions, and the predicted failure distribution can be estimated with reliability methods such as Weibull Analysis (Type I Prognostics). As the component operates, it begins to degrade and consume its available life. This life consumption may be a function of system stresses, and the failure distribution should be updated to account for the system operational stress levels (Type II Prognostics). When degradation becomes apparent, this information can be used to again improve the RUL estimate (Type III Prognostics). This research focused on developing prognostics algorithms for the three types of prognostics, developing uncertainty quantification methods for each of the algorithms, and, most importantly, developing a framework using Bayesian methods to transition between prognostic model types and update failure distribution estimates as new information becomes available. The developed methods were then validated on a range of accelerated degradation test beds. The ultimate goal of prognostics is to provide an accurate

Orthogonal series generalized likelihood ratio test for failure detection and isolation. [for aircraft control

NASA Technical Reports Server (NTRS)

Hall, Steven R.; Walker, Bruce K.

1990-01-01

A new failure detection and isolation algorithm for linear dynamic systems is presented. This algorithm, the Orthogonal Series Generalized Likelihood Ratio (OSGLR) test, is based on the assumption that the failure modes of interest can be represented by truncated series expansions. This assumption leads to a failure detection algorithm with several desirable properties. Computer simulation results are presented for the detection of the failures of actuators and sensors of a C-130 aircraft. The results show that the OSGLR test generally performs as well as the GLR test in terms of time to detect a failure and is more robust to failure mode uncertainty. However, the OSGLR test is also somewhat more sensitive to modeling errors than the GLR test.

The role of exercise testing in heart failure.

PubMed

Swedberg, K; Gundersen, T

1993-01-01

The objectives of exercise testing in congestive heart failure (CHF) may be summarized as follows: (a) detect impaired cardiac performance, (b) grade severity of cardiac failure and classify functional capability, and (c) assess effects of interventions. Several different methods are available to make these assessments, and we have to ask ourselves how well exercise testing achieves these objectives. It has to be kept in mind that the power generated by the exercising muscles is dependent on the oxygen delivery to the skeletal muscles. Oxygen uptake is the result of an integrated performance of the lungs, heart, and peripheral circulation. In patients, as well as in normal subjects, oxygen uptake is related to hemodynamic indices such as cardiac output, stroke volume, or exercise duration when a stepwise regulated maximal exercise protocol is used. However, there are major differences in the concept of a true maximum in normal subjects versus heart failure patients. Fit-normal subjects will achieve a real maximal oxygen uptake, whereas patients may stop testing before a maximum is reached because of symptoms such as dyspnea or leg fatigue. Therefore, it is better if the actual oxygen uptake can be measured. "Peak" rather than true maximal oxygen uptake has been suggested for the classification of the severity of heart failure. Peripheral factors modify the cardiac output through such factors as vascular resistance, organ function, and hormonal release. Maximal exercise will stress the cardiovascular system to a point where the weakest chain will impose a limiting effect.(ABSTRACT TRUNCATED AT 250 WORDS)

Simulating direct shear tests with the Bullet physics library: A validation study.

PubMed

Izadi, Ehsan; Bezuijen, Adam

2018-01-01

This study focuses on the possible uses of physics engines, and more specifically the Bullet physics library, to simulate granular systems. Physics engines are employed extensively in the video gaming, animation and movie industries to create physically plausible scenes. They are designed to deliver a fast, stable, and optimal simulation of certain systems such as rigid bodies, soft bodies and fluids. This study focuses exclusively on simulating granular media in the context of rigid body dynamics with the Bullet physics library. The first step was to validate the results of the simulations of direct shear testing on uniform-sized metal beads on the basis of laboratory experiments. The difference in the average angle of mobilized frictions was found to be only 1.0°. In addition, a very close match was found between dilatancy in the laboratory samples and in the simulations. A comprehensive study was then conducted to determine the failure and post-failure mechanism. We conclude with the presentation of a simulation of a direct shear test on real soil which demonstrated that Bullet has all the capabilities needed to be used as software for simulating granular systems.

Initial Teacher Licensure Testing in Tennessee: Test Validation.

ERIC Educational Resources Information Center

Bowman, Harry L.; Petry, John R.

In 1988 a study was conducted to determine the validity of candidate teacher licensure examinations for use in Tennessee under the 1984 Comprehensive Education Reform Act. The Department of Education conducted a study to determine the validity of 11 previously unvalidated or extensively revised tests for certification and to make recommendations…

Evaluating Test Validity: Reprise and Progress

ERIC Educational Resources Information Center

Shepard, Lorrie A.

2016-01-01

The AERA, APA, NCME Standards define validity as "the degree to which evidence and theory support the interpretations of test scores for proposed uses of tests". A century of disagreement about validity does not mean that there has not been substantial progress. This consensus definition brings together interpretations and use so that it…

Construct Validity of Neuropsychological Tests in Schizophrenia.

ERIC Educational Resources Information Center

Allen, Daniel N.; Aldarondo, Felito; Goldstein, Gerald; Huegel, Stephen G.; Gilbertson, Mark; van Kammen, Daniel P.

1998-01-01

The construct validity of neuropsychological tests in patients with schizophrenia was studied with 39 patients who were evaluated with a battery of six tests assessing attention, memory, and abstract reasoning abilities. Results support the construct validity of the neuropsychological tests in patients with schizophrenia. (SLD)

Valid methods: the quality assurance of test method development, validation, approval, and transfer for veterinary testing laboratories.

PubMed

Wiegers, Ann L

2003-07-01

Third-party accreditation is a valuable tool to demonstrate a laboratory's competence to conduct testing. Accreditation, internationally and in the United States, has been discussed previously. However, accreditation is only I part of establishing data credibility. A validated test method is the first component of a valid measurement system. Validation is defined as confirmation by examination and the provision of objective evidence that the particular requirements for a specific intended use are fulfilled. The international and national standard ISO/IEC 17025 recognizes the importance of validated methods and requires that laboratory-developed methods or methods adopted by the laboratory be appropriate for the intended use. Validated methods are therefore required and their use agreed to by the client (i.e., end users of the test results such as veterinarians, animal health programs, and owners). ISO/IEC 17025 also requires that the introduction of methods developed by the laboratory for its own use be a planned activity conducted by qualified personnel with adequate resources. This article discusses considerations and recommendations for the conduct of veterinary diagnostic test method development, validation, evaluation, approval, and transfer to the user laboratory in the ISO/IEC 17025 environment. These recommendations are based on those of nationally and internationally accepted standards and guidelines, as well as those of reputable and experienced technical bodies. They are also based on the author's experience in the evaluation of method development and transfer projects, validation data, and the implementation of quality management systems in the area of method development.

Alternative Vocabularies in the Test Validity Literature

ERIC Educational Resources Information Center

Markus, Keith A.

2016-01-01

Justification of testing practice involves moving from one state of knowledge about the test to another. Theories of test validity can (a) focus on the beginning of the process, (b) focus on the end, or (c) encompass the entire process. Analyses of four case studies test and illustrate three claims: (a) restrictions on validity entail a supplement…

Alphabus Mechanical Validation Plan and Test Campaign

NASA Astrophysics Data System (ADS)

Calvisi, G.; Bonnet, D.; Belliol, P.; Lodereau, P.; Redoundo, R.

2012-07-01

A joint team of the two leading European satellite companies (Astrium and Thales Alenia Space) worked with the support of ESA and CNES to define a product line able to efficiently address the upper segment of communications satellites : Alphabus Starting in 2009 and up to 2011 the mechanical validation of the Alphabus platform has been obtained thanks to static tests performed on dedicated static model and to environmental test performed on the first satellite based on Alphabus: Alphasat I-XL. The mechanical validation of the Alphabus platform presented an excellent opportunity to improve the validation and qualification process, with respect to static, sine vibrations, acoustic and L/V shock environment, minimizing recurrent cost of manufacturing, integration and testing. A main driver on mechanical testing is that mechanical acceptance testing at satellite level will be performed with empty tanks due to technical constraints (limitation of existing vibration devices) and programmatic advantages (test risk reduction, test schedule minimization). In this paper the impacts that such testing logic have on validation plan are briefly recalled and its actual application for Alphasat PFM mechanical test campaign is detailed.

Derivation and validation of a simple clinical risk-model in heart failure based on 6 minute walk test performance and NT-proBNP status--do we need specificity for sex and beta-blockers?

PubMed

Frankenstein, L; Goode, K; Ingle, L; Remppis, A; Schellberg, D; Nelles, M; Katus, H A; Clark, A L; Cleland, J G F; Zugck, C

2011-02-17

It is unclear whether risk prediction strategies in chronic heart failure (CHF) need to be specific for sex or beta-blockers. We examined this problem and developed and validated the consequent risk models based on 6-minute-walk-test and NT-proBNP. The derivation cohort comprised 636 German patients with systolic dysfunction. They were validated against 676 British patients with similar aetiology. ROC-curves for 1-year mortality identified cut-off values separately for specificity (none, sex, beta-blocker, both). Patients were grouped according to number of cut-offs met (group I/II/III - 0/1/2 cut-offs). Widest separation between groups was achieved with sex- and beta-blocker-specific cut offs. In the derivation population, 1-year mortality was 0%, 8%, 31% for group I, II and III, respectively. In the validation population, 1-year rates in the three risk groups were 2%, 7%, 14%, respectively, after application of the same cut-offs. Risk stratification for CHF should perhaps take sex and beta-blocker usage into account. We derived and independently validated relevant risk models based on 6-minute-walk-tests and NT-proBNP. Specifying sex and use of beta-blockers identified three distinct sub-groups with widely differing prognosis. In clinical practice, it may be appropriate to tailor the intensity of follow-up and/or the treatment strategy according to the risk-group. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

Photovoltaic module reliability improvement through application testing and failure analysis

NASA Technical Reports Server (NTRS)

Dumas, L. N.; Shumka, A.

1982-01-01

During the first four years of the U.S. Department of Energy (DOE) National Photovoltatic Program, the Jet Propulsion Laboratory Low-Cost Solar Array (LSA) Project purchased about 400 kW of photovoltaic modules for test and experiments. In order to identify, report, and analyze test and operational problems with the Block Procurement modules, a problem/failure reporting and analysis system was implemented by the LSA Project with the main purpose of providing manufacturers with feedback from test and field experience needed for the improvement of product performance and reliability. A description of the more significant types of failures is presented, taking into account interconnects, cracked cells, dielectric breakdown, delamination, and corrosion. Current design practices and reliability evaluations are also discussed. The conducted evaluation indicates that current module designs incorporate damage-resistant and fault-tolerant features which address field failure mechanisms observed to date.

A Note on Economic Content and Test Validity.

ERIC Educational Resources Information Center

Soper, John C.; Brenneke, Judith Staley

1987-01-01

Offers practical tips on how teachers can determine whether classroom tests are actually measuring what they are designed to measure. Discusses criterion-related validity, construct validity, and content validity. Demonstrates how to determine the degree of content validity a particular test may have for a particular course or unit. (Author/DH)

Validation of the Lollipop Test: A Diagnostic Screening Test of School Readiness.

ERIC Educational Resources Information Center

Chew, Alex L.; Morris, John D.

1984-01-01

The validity of the Lollipop Test: A Diagnostic Screening Test of School Readiness was examined using the Metropolitan Readiness Test (MRT), Level I, Form Q, as the criterion. Appreciable concurrent validity was found across test batteries. Implications for school readiness screening are discussed. (Author/BS)

Development Testing and Subsequent Failure Investigation of a Spring Strut Mechanism

NASA Technical Reports Server (NTRS)

Dervan, Jared; Robertson, Brandan; Staab, Lucas; Culberson, Michael; Pellicciotti, Joseph

2014-01-01

The NASA Engineering and Safety Center (NESC) and Lockheed Martin (LM) performed random vibration testing on a single spring strut development unit to assess its ability to withstand qualification level random vibration environments. Failure of the strut while exposed to random vibration resulted in a follow-on failure investigation, design changes, and additional development tests. This paper focuses on the results of the failure investigations referenced in detail in the NESC final report [1] including identified lessons learned to aid in future design iterations of the spring strut and to help other mechanism developers avoid similar pitfalls.

Development Testing and Subsequent Failure Investigation of a Spring Strut Mechanism

NASA Technical Reports Server (NTRS)

Dervan, Jared; Robertson, Brandon; Staab, Lucas; Culberson, Michael; Pellicciotti, Joseph

2014-01-01

The NASA Engineering and Safety Center (NESC) and Lockheed Martin (LM) performed random vibration testing on a single spring strut development unit to assess its ability to withstand qualification level random vibration environments. Failure of the strut while exposed to random vibration resulted in a follow-on failure investigation, design changes, and additional development tests. This paper focuses on the results of the failure investigations referenced in detail in the NESC final report including identified lessons learned to aid in future design iterations of the spring strut and to help other mechanism developers avoid similar pitfalls.

Verification and Validation of Adaptive and Intelligent Systems with Flight Test Results

NASA Technical Reports Server (NTRS)

Burken, John J.; Larson, Richard R.

2009-01-01

F-15 IFCS project goals are: a) Demonstrate Control Approaches that can Efficiently Optimize Aircraft Performance in both Normal and Failure Conditions [A] & [B] failures. b) Advance Neural Network-Based Flight Control Technology for New Aerospace Systems Designs with a Pilot in the Loop. Gen II objectives include; a) Implement and Fly a Direct Adaptive Neural Network Based Flight Controller; b) Demonstrate the Ability of the System to Adapt to Simulated System Failures: 1) Suppress Transients Associated with Failure; 2) Re-Establish Sufficient Control and Handling of Vehicle for Safe Recovery. c) Provide Flight Experience for Development of Verification and Validation Processes for Flight Critical Neural Network Software.

Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project: Test act system validation

NASA Technical Reports Server (NTRS)

1985-01-01

The primary objective of the Test Active Control Technology (ACT) System laboratory tests was to verify and validate the system concept, hardware, and software. The initial lab tests were open loop hardware tests of the Test ACT System as designed and built. During the course of the testing, minor problems were uncovered and corrected. Major software tests were run. The initial software testing was also open loop. These tests examined pitch control laws, wing load alleviation, signal selection/fault detection (SSFD), and output management. The Test ACT System was modified to interface with the direct drive valve (DDV) modules. The initial testing identified problem areas with DDV nonlinearities, valve friction induced limit cycling, DDV control loop instability, and channel command mismatch. The other DDV issue investigated was the ability to detect and isolate failures. Some simple schemes for failure detection were tested but were not completely satisfactory. The Test ACT System architecture continues to appear promising for ACT/FBW applications in systems that must be immune to worst case generic digital faults, and be able to tolerate two sequential nongeneric faults with no reduction in performance. The challenge in such an implementation would be to keep the analog element sufficiently simple to achieve the necessary reliability.

14 CFR 91.1041 - Aircraft proving and validation tests.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Aircraft proving and validation tests. 91... Ownership Operations Program Management § 91.1041 Aircraft proving and validation tests. (a) No program... tests. However, pilot flight training may be conducted during the proving tests. (d) Validation testing...

14 CFR 91.1041 - Aircraft proving and validation tests.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Aircraft proving and validation tests. 91... Ownership Operations Program Management § 91.1041 Aircraft proving and validation tests. (a) No program... tests. However, pilot flight training may be conducted during the proving tests. (d) Validation testing...

14 CFR 91.1041 - Aircraft proving and validation tests.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Aircraft proving and validation tests. 91... Ownership Operations Program Management § 91.1041 Aircraft proving and validation tests. (a) No program... tests. However, pilot flight training may be conducted during the proving tests. (d) Validation testing...

14 CFR 91.1041 - Aircraft proving and validation tests.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Aircraft proving and validation tests. 91... Ownership Operations Program Management § 91.1041 Aircraft proving and validation tests. (a) No program... tests. However, pilot flight training may be conducted during the proving tests. (d) Validation testing...

14 CFR 91.1041 - Aircraft proving and validation tests.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aircraft proving and validation tests. 91... Ownership Operations Program Management § 91.1041 Aircraft proving and validation tests. (a) No program... tests. However, pilot flight training may be conducted during the proving tests. (d) Validation testing...

Cycle life test and failure model of nickel-hydrogen cells

NASA Technical Reports Server (NTRS)

Smithrick, J. J.

1983-01-01

Six ampere hour individual pressure vessel nickel hydrogen cells were charge/discharge cycled to failure. Failure as used here is defined to occur when the end of discharge voltage degraded to 0.9 volts. They were cycled under a low earth orbit cycle regime to a deep depth of discharge (80 percent of rated ampere hour capacity). Both cell designs were fabricated by the same manufacturer and represent current state of the art. A failure model was advanced which suggests both cell designs have inadequate volume tolerance characteristics. The limited existing data base at a deep depth of discharge (DOD) was expanded. Two cells of each design were cycled. One COMSAT cell failed at cycle 1712 and the other failed at cycle 1875. For the Air Force/Hughes cells, one cell failed at cycle 2250 and the other failed at cycle 2638. All cells, of both designs, failed due to low end of discharge voltage (0.9 volts). No cell failed due to electrical shorts. After cell failure, three different reconditioning tests (deep discharge, physical reorientation, and open circuit voltage stand) were conducted on all cells of each design. A fourth reconditioning test (electrolyte addition) was conducted on one cell of each design. In addition post cycle cell teardown and failure analysis were performed on the one cell of each design which did not have electrolyte added after failure.

Evidence of Construct Validity in Published Achievement Tests.

ERIC Educational Resources Information Center

Nolet, Victor; Tindal, Gerald

Valid interpretation of test scores is the shared responsibility of the test designer and the test user. Test publishers must provide evidence of the validity of the decisions their tests are intended to support, while test users are responsible for analyzing this evidence and subsequently using the test in the manner indicated by the publisher.…

Personality Changes as a Function of Minimum Competency Test Success or Failure.

ERIC Educational Resources Information Center

Richman, Charles L.; And Others

1987-01-01

The psychological effects of success and failure on the North Carolina Minimum Competency Test (MCT) were examined. Subjects were high school students, who were pre- and post-tested using the Rosenberg Self Esteem Scale and the High School Personality Questionnaire. Self-esteem decreased following knowledge of MCT failure. (LMO)

Validation and Potential Mechanisms of Red Cell Distribution Width as a Prognostic Marker in Heart Failure

PubMed Central

ALLEN, LARRY A.; FELKER, G. MICHAEL; MEHRA, MANDEEP R.; CHIONG, JUN R.; DUNLAP, STEPHANIE H.; GHALI, JALAL K.; LENIHAN, DANIEL J.; OREN, RON M.; WAGONER, LYNNE E.; SCHWARTZ, TODD A.; ADAMS, KIRKWOOD F.

2014-01-01

Background: Adverse outcomes have recently been linked to elevated red cell distribution width (RDW) in heart failure. Our study sought to validate the prognostic value of RDW in heart failure and to explore the potential mechanisms underlying this association. Methods and Results: Data from the Study of Anemia in a Heart Failure Population (STAMINA-HFP) registry, a prospective, multicenter cohort of ambulatory patients with heart failure supported multivariable modeling to assess relationships between RDW and outcomes. The association between RDW and iron metabolism, inflammation, and neurohormonal activation was studied in a separate cohort of heart failure patients from the United Investigators to Evaluate Heart Failure (UNITE-HF) Biomarker registry. RDW was independently predictive of outcome (for each 1% increase in RDW, hazard ratio for mortality 1.06, 95% CI 1.01-1.12; hazard ratio for hospitalization or mortality 1.06; 95% CI 1.02-1.10) after adjustment for other covariates. Increasing RDW correlated with decreasing hemoglobin, increasing interleukin-6, and impaired iron mobilization. Conclusions: Our results confirm previous observations that RDW is a strong, independent predictor of adverse outcome in chronic heart failure and suggest elevated RDW may indicate inflammatory stress and impaired iron mobilization. These findings encourage further research into the relationship between heart failure and the hematologic system. PMID:20206898

Validation and potential mechanisms of red cell distribution width as a prognostic marker in heart failure.

PubMed

Allen, Larry A; Felker, G Michael; Mehra, Mandeep R; Chiong, Jun R; Dunlap, Stephanie H; Ghali, Jalal K; Lenihan, Daniel J; Oren, Ron M; Wagoner, Lynne E; Schwartz, Todd A; Adams, Kirkwood F

2010-03-01

Adverse outcomes have recently been linked to elevated red cell distribution width (RDW) in heart failure. Our study sought to validate the prognostic value of RDW in heart failure and to explore the potential mechanisms underlying this association. Data from the Study of Anemia in a Heart Failure Population (STAMINA-HFP) registry, a prospective, multicenter cohort of ambulatory patients with heart failure supported multivariable modeling to assess relationships between RDW and outcomes. The association between RDW and iron metabolism, inflammation, and neurohormonal activation was studied in a separate cohort of heart failure patients from the United Investigators to Evaluate Heart Failure (UNITE-HF) Biomarker registry. RDW was independently predictive of outcome (for each 1% increase in RDW, hazard ratio for mortality 1.06, 95% CI 1.01-1.12; hazard ratio for hospitalization or mortality 1.06; 95% CI 1.02-1.10) after adjustment for other covariates. Increasing RDW correlated with decreasing hemoglobin, increasing interleukin-6, and impaired iron mobilization. Our results confirm previous observations that RDW is a strong, independent predictor of adverse outcome in chronic heart failure and suggest elevated RDW may indicate inflammatory stress and impaired iron mobilization. These findings encourage further research into the relationship between heart failure and the hematologic system. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Validity and reliability of the NAB Naming Test.

PubMed

Sachs, Bonnie C; Rush, Beth K; Pedraza, Otto

2016-05-01

Confrontation naming is commonly assessed in neuropsychological practice, but few standardized measures of naming exist and those that do are susceptible to the effects of education and culture. The Neuropsychological Assessment Battery (NAB) Naming Test is a 31-item measure used to assess confrontation naming. Despite adequate psychometric information provided by the test publisher, there has been limited independent validation of the test. In this study, we investigated the convergent and discriminant validity, internal consistency, and alternate forms reliability of the NAB Naming Test in a sample of adults (Form 1: n = 247, Form 2: n = 151) clinically referred for neuropsychological evaluation. Results indicate adequate-to-good internal consistency and alternate forms reliability. We also found strong convergent validity as demonstrated by relationships with other neurocognitive measures. We found preliminary evidence that the NAB Naming Test demonstrates a more pronounced ceiling effect than other commonly used measures of naming. To our knowledge, this represents the largest published independent validation study of the NAB Naming Test in a clinical sample. Our findings suggest that the NAB Naming Test demonstrates adequate validity and reliability and merits consideration in the test arsenal of clinical neuropsychologists.

Development and validation of a prognostic score to predict mortality in patients with acute-on-chronic liver failure.

PubMed

Jalan, Rajiv; Saliba, Faouzi; Pavesi, Marco; Amoros, Alex; Moreau, Richard; Ginès, Pere; Levesque, Eric; Durand, Francois; Angeli, Paolo; Caraceni, Paolo; Hopf, Corinna; Alessandria, Carlo; Rodriguez, Ezequiel; Solis-Muñoz, Pablo; Laleman, Wim; Trebicka, Jonel; Zeuzem, Stefan; Gustot, Thierry; Mookerjee, Rajeshwar; Elkrief, Laure; Soriano, German; Cordoba, Joan; Morando, Filippo; Gerbes, Alexander; Agarwal, Banwari; Samuel, Didier; Bernardi, Mauro; Arroyo, Vicente

2014-11-01

Acute-on-chronic liver failure (ACLF) is a frequent syndrome (30% prevalence), characterized by acute decompensation of cirrhosis, organ failure(s) and high short-term mortality. This study develops and validates a specific prognostic score for ACLF patients. Data from 1349 patients included in the CANONIC study were used. First, a simplified organ function scoring system (CLIF Consortium Organ Failure score, CLIF-C OFs) was developed to diagnose ACLF using data from all patients. Subsequently, in 275 patients with ACLF, CLIF-C OFs and two other independent predictors of mortality (age and white blood cell count) were combined to develop a specific prognostic score for ACLF (CLIF Consortium ACLF score [CLIF-C ACLFs]). A concordance index (C-index) was used to compare the discrimination abilities of CLIF-C ACLF, MELD, MELD-sodium (MELD-Na), and Child-Pugh (CPs) scores. The CLIF-C ACLFs was validated in an external cohort and assessed for sequential use. The CLIF-C ACLFs showed a significantly higher predictive accuracy than MELDs, MELD-Nas, and CPs, reducing (19-28%) the corresponding prediction error rates at all main time points after ACLF diagnosis (28, 90, 180, and 365 days) in both the CANONIC and the external validation cohort. CLIF-C ACLFs computed at 48 h, 3-7 days, and 8-15 days after ACLF diagnosis predicted the 28-day mortality significantly better than at diagnosis. The CLIF-C ACLFs at ACLF diagnosis is superior to the MELDs and MELD-Nas in predicting mortality. The CLIF-C ACLFs is a clinically relevant, validated scoring system that can be used sequentially to stratify the risk of mortality in ACLF patients. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

College Text Test Validity.

ERIC Educational Resources Information Center

McAfee, Donald C.

1979-01-01

A team of faculty members and graduate students identified major concepts and developed validated test questions for two widely used textbooks in personal hygiene classes in order to standardize norms for classes and supplement inadequate instructor's manuals. (JMF)

Validity testing and neuropsychology practice in the VA healthcare system: results from recent practitioner survey (.).

PubMed

Young, J Christopher; Roper, Brad L; Arentsen, Timothy J

2016-05-01

A survey of neuropsychologists in the Veterans Health Administration examined symptom/performance validity test (SPVT) practices and estimated base rates for patient response bias. Invitations were emailed to 387 psychologists employed within the Veterans Affairs (VA), identified as likely practicing neuropsychologists, resulting in 172 respondents (44.4% response rate). Practice areas varied, with 72% at least partially practicing in general neuropsychology clinics and 43% conducting VA disability exams. Mean estimated failure rates were 23.0% for clinical outpatient, 12.9% for inpatient, and 39.4% for disability exams. Failure rates were the highest for mTBI and PTSD referrals. Failure rates were positively correlated with the number of cases seen and frequency and number of SPVT use. Respondents disagreed regarding whether one (45%) or two (47%) failures are required to establish patient response bias, with those administering more measures employing the more stringent criterion. Frequency of the use of specific SPVTs is reported. Base rate estimates for SPVT failure in VA disability exams are comparable to those in other medicolegal settings. However, failure in routine clinical exams is much higher in the VA than in other settings, possibly reflecting the hybrid nature of the VA's role in both healthcare and disability determination. Generally speaking, VA neuropsychologists use SPVTs frequently and eschew pejorative terms to describe their failure. Practitioners who require only one SPVT failure to establish response bias may overclassify patients. Those who use few or no SPVTs may fail to identify response bias. Additional clinical and theoretical implications are discussed.

Evaluating the Content Validity of Multistage-Adaptive Tests

ERIC Educational Resources Information Center

Crotts, Katrina; Sireci, Stephen G.; Zenisky, April

2012-01-01

Validity evidence based on test content is important for educational tests to demonstrate the degree to which they fulfill their purposes. Most content validity studies involve subject matter experts (SMEs) who rate items that comprise a test form. In computerized-adaptive testing, examinees take different sets of items and test "forms"…

15 CFR 995.27 - Format validation software testing.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 15 Commerce and Foreign Trade 3 2013-01-01 2013-01-01 false Format validation software testing... of NOAA ENC Products § 995.27 Format validation software testing. Tests shall be performed verifying, as far as reasonable and practicable, that CEVAD's data testing software performs the checks, as...

15 CFR 995.27 - Format validation software testing.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 15 Commerce and Foreign Trade 3 2014-01-01 2014-01-01 false Format validation software testing... of NOAA ENC Products § 995.27 Format validation software testing. Tests shall be performed verifying, as far as reasonable and practicable, that CEVAD's data testing software performs the checks, as...

15 CFR 995.27 - Format validation software testing.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 15 Commerce and Foreign Trade 3 2012-01-01 2012-01-01 false Format validation software testing... of NOAA ENC Products § 995.27 Format validation software testing. Tests shall be performed verifying, as far as reasonable and practicable, that CEVAD's data testing software performs the checks, as...

15 CFR 995.27 - Format validation software testing.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 15 Commerce and Foreign Trade 3 2011-01-01 2011-01-01 false Format validation software testing... of NOAA ENC Products § 995.27 Format validation software testing. Tests shall be performed verifying, as far as reasonable and practicable, that CEVAD's data testing software performs the checks, as...

15 CFR 995.27 - Format validation software testing.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 15 Commerce and Foreign Trade 3 2010-01-01 2010-01-01 false Format validation software testing... CERTIFICATION REQUIREMENTS FOR NOAA HYDROGRAPHIC PRODUCTS AND SERVICES CERTIFICATION REQUIREMENTS FOR... of NOAA ENC Products § 995.27 Format validation software testing. Tests shall be performed verifying...

14 CFR 135.145 - Aircraft proving and validation tests.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Aircraft proving and validation tests. 135... Aircraft and Equipment § 135.145 Aircraft proving and validation tests. (a) No certificate holder may...) Validation testing is required to determine that a certificate holder is capable of conducting operations...

14 CFR 135.145 - Aircraft proving and validation tests.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Aircraft proving and validation tests. 135... Aircraft and Equipment § 135.145 Aircraft proving and validation tests. (a) No certificate holder may...) Validation testing is required to determine that a certificate holder is capable of conducting operations...

14 CFR 135.145 - Aircraft proving and validation tests.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Aircraft proving and validation tests. 135... Aircraft and Equipment § 135.145 Aircraft proving and validation tests. (a) No certificate holder may...) Validation testing is required to determine that a certificate holder is capable of conducting operations...

14 CFR 135.145 - Aircraft proving and validation tests.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Aircraft proving and validation tests. 135... Aircraft and Equipment § 135.145 Aircraft proving and validation tests. (a) No certificate holder may...) Validation testing is required to determine that a certificate holder is capable of conducting operations...

14 CFR 135.145 - Aircraft proving and validation tests.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Aircraft proving and validation tests. 135... Aircraft and Equipment § 135.145 Aircraft proving and validation tests. (a) No certificate holder may...) Validation testing is required to determine that a certificate holder is capable of conducting operations...

Numerical Simulation and Experimental Validation of Failure Caused by Vibration of a Fan

NASA Astrophysics Data System (ADS)

Zhou, Qiang; Han, Wu; Feng, Jianmei; Jia, Xiaohan; Peng, Xueyuan

2017-08-01

This paper presents the root cause analysis of an unexpected fracture occurred on the blades of a motor fan used in a natural gas reciprocating compressor unit. A finite element model was established to investigate the natural frequencies and modal shapes of the fan, and a modal test was performed to verify the numerical results. It was indicated that the numerical results agreed well with experimental data. The third order natural frequency was close to the six times excitation frequency, and the corresponding modal shape was the combination of bending and torsional vibration, which consequently contributed to low-order resonance and fracture failure of the fan. The torsional moment obtained by a torsional vibration analysis of the compressor shaft system was exerted on the numerical model of the fan to evaluate the dynamic stress response of the fan. The results showed that the stress concentration regions on the numerical model were consistent with the location of fractures on the fan. Based on the numerical simulation and experimental validation, some recommendations were given to improve the reliability of the motor fan.

Failure in laboratory fault models in triaxial tests

USGS Publications Warehouse

Savage, J.C.; Lockner, D.A.; Byerlee, J.D.

1996-01-01

A model of a fault in the Earth is a sand-filled saw cut in a granite cylinder subjected to a triaxial test. The saw cut is inclined at an angle a to the cylinder axis, and the sand filling is intended to represent gouge. The triaxial test subjects the granite cylinder to a constant confining pressure and increasing axial stress to maintain a constant rate of shortening of the cylinder. The required axial stress increases at a decreasing rate to a maximum, beyond which a roughly constant axial stress is sufficient to maintain the constant rate of shortening: Such triaxial tests were run for saw cuts inclined at angles ?? of 20??, 25??, 30??, 35??, 40??, 45??, and 50?? to the cylinder axis, and the apparent coefficient of friction ??a (ratio of the shear stress to the normal stress, both stresses resolved onto the saw cut) at failure was determined. Subject to the assumption that the observed failure involves slip on Coulomb shears (orientation unspecified), the orientation of the principal compression axis within the gouge can be calculated as a function of ??a for a given value of the coefficient of internal friction ??i. The rotation of the principal stress axes within the gouge in a triaxial test can then be followed as the shear strain across the gouge layer increases. For ??i ??? 0.8, an appropriate value for highly sheared sand, the observed values ??a imply that the principal-axis of compression within the gouge rotates so as to approach being parallel to the cylinder axis for all saw cut angles (20?? < ?? < 50??). In the limiting state (principal compression axis parallel to cylinder axis) the stress state in the gouge layer would be the same as that in the granite cylinder, and the failure criterion would be independent of the saw cut angle.

Construct Validity of the Nepalese School Leaving English Reading Test

ERIC Educational Resources Information Center

Dawadi, Saraswati; Shrestha, Prithvi N.

2018-01-01

There has been a steady interest in investigating the validity of language tests in the last decades. Despite numerous studies on construct validity in language testing, there are not many studies examining the construct validity of a reading test. This paper reports on a study that explored the construct validity of the English reading test in…

Psychometric properties of the Symptom Status Questionnaire-Heart Failure.

PubMed

Heo, Seongkum; Moser, Debra K; Pressler, Susan J; Dunbar, Sandra B; Mudd-Martin, Gia; Lennie, Terry A

2015-01-01

Many patients with heart failure (HF) experience physical symptoms, poor health-related quality of life (HRQOL), and high rates of hospitalization. Physical symptoms are associated with HRQOL and are major antecedents of hospitalization. However, reliable and valid physical symptom instruments have not been established. Therefore, this study examined the psychometric properties of the Symptom Status Questionnaire-Heart Failure (SSQ-HF) in patients with HF. Data on symptoms using the SSQ-HF were collected from 249 patients (aged 61 years, 67% male, 45% in New York Heart Association functional class III/IV). Internal consistency reliability was assessed using Cronbach's α. Item homogeneity was assessed using item-total and interitem correlations. Construct validity was assessed using factor analysis and testing hypotheses on known relationships. Data on depressive symptoms (Beck Depression Inventory II), HRQOL (Minnesota Living With Heart Failure Questionnaire), and event-free survival were collected to test known relationships. Internal consistency reliability was supported: Cronbach's α was .80. Item-total correlation coefficients and interitem correlation coefficients were acceptable. Factor analysis supported the construct validity of the instrument. More severe symptoms were associated with more depressive symptoms, poorer HRQOL, and more risk for hospitalization, emergency department visit, or death, controlling for covariates. The findings of this study support the reliability and validity of the SSQ-HF. Clinicians and researchers can use this instrument to assess physical symptoms in patients with HF.

Preliminary Failure Modes and Effects Analysis of the US DCLL Test Blanket Module

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

Lee C. Cadwallader

2010-06-01

This report presents the results of a preliminary failure modes and effects analysis (FMEA) of a small tritium-breeding test blanket module design for the International Thermonuclear Experimental Reactor. The FMEA was quantified with “generic” component failure rate data, and the failure events are binned into postulated initiating event families and frequency categories for safety assessment. An appendix to this report contains repair time data to support an occupational radiation exposure assessment for test blanket module maintenance.

Preliminary Failure Modes and Effects Analysis of the US DCLL Test Blanket Module

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

Lee C. Cadwallader

2007-08-01

This report presents the results of a preliminary failure modes and effects analysis (FMEA) of a small tritium-breeding test blanket module design for the International Thermonuclear Experimental Reactor. The FMEA was quantified with “generic” component failure rate data, and the failure events are binned into postulated initiating event families and frequency categories for safety assessment. An appendix to this report contains repair time data to support an occupational radiation exposure assessment for test blanket module maintenance.

Development Testing and Subsequent Failure Investigation of a Spring Strut Mechanism

NASA Technical Reports Server (NTRS)

Dervan, Jared; Robertson, Brandon; Staab, Lucas; Culberson, Michael

2014-01-01

Commodities are transferred between the Multi-Purpose Crew Vehicle (MPCV) crew module (CM) and service module (SM) via an external umbilical that is driven apart with spring-loaded struts after the structural connection is severed. The spring struts must operate correctly for the modules to separate safely. There was no vibration testing of strut development units scoped in the MPCV Program Plan; therefore, any design problems discovered as a result of vibration testing would not have been found until the component qualification. The NASA Engineering and Safety Center (NESC) and Lockheed Martin (LM) performed random vibration testing on a single spring strut development unit to assess its ability to withstand qualification level random vibration environments. Failure of the strut while exposed to random vibration resulted in a follow-on failure investigation, design changes, and additional development tests. This paper focuses on the results of the failure investigations including identified lessons learned and best practices to aid in future design iterations of the spring strut and to help other mechanism developers avoid similar pitfalls.

Estimation procedures to measure and monitor failure rates of components during thermal-vacuum testing

NASA Technical Reports Server (NTRS)

Williams, R. E.; Kruger, R.

1980-01-01

Estimation procedures are described for measuring component failure rates, for comparing the failure rates of two different groups of components, and for formulating confidence intervals for testing hypotheses (based on failure rates) that the two groups perform similarly or differently. Appendix A contains an example of an analysis in which these methods are applied to investigate the characteristics of two groups of spacecraft components. The estimation procedures are adaptable to system level testing and to monitoring failure characteristics in orbit.

Numerical simulation of failure behavior of granular debris flows based on flume model tests.

PubMed

Zhou, Jian; Li, Ye-xun; Jia, Min-cai; Li, Cui-na

2013-01-01

In this study, the failure behaviors of debris flows were studied by flume model tests with artificial rainfall and numerical simulations (PFC(3D)). Model tests revealed that grain sizes distribution had profound effects on failure mode, and the failure in slope of medium sand started with cracks at crest and took the form of retrogressive toe sliding failure. With the increase of fine particles in soil, the failure mode of the slopes changed to fluidized flow. The discrete element method PFC(3D) can overcome the hypothesis of the traditional continuous medium mechanic and consider the simple characteristics of particle. Thus, a numerical simulations model considering liquid-solid coupled method has been developed to simulate the debris flow. Comparing the experimental results, the numerical simulation result indicated that the failure mode of the failure of medium sand slope was retrogressive toe sliding, and the failure of fine sand slope was fluidized sliding. The simulation result is consistent with the model test and theoretical analysis, and grain sizes distribution caused different failure behavior of granular debris flows. This research should be a guide to explore the theory of debris flow and to improve the prevention and reduction of debris flow.

Test Takers and the Validity of Score Interpretations

ERIC Educational Resources Information Center

Kopriva, Rebecca J.; Thurlow, Martha L.; Perie, Marianne; Lazarus, Sheryl S.; Clark, Amy

2016-01-01

This article argues that test takers are as integral to determining validity of test scores as defining target content and conditioning inferences on test use. A principled sustained attention to how students interact with assessment opportunities is essential, as is a principled sustained evaluation of evidence confirming the validity or calling…

Determination of fiber-matrix interface failure parameters from off-axis tests

NASA Technical Reports Server (NTRS)

Naik, Rajiv A.; Crews, John H., Jr.

1993-01-01

Critical fiber-matrix (FM) interface strength parameters were determined using a micromechanics-based approach together with failure data from off-axis tension (OAT) tests. The ply stresses at failure for a range of off-axis angles were used as input to a micromechanics analysis that was performed using the personal computer-based MICSTRAN code. FM interface stresses at the failure loads were calculated for both the square and the diamond array models. A simple procedure was developed to determine which array had the more severe FM interface stresses and the location of these critical stresses on the interface. For the cases analyzed, critical FM interface stresses were found to occur with the square array model and were located at a point where adjacent fibers were closest together. The critical FM interface stresses were used together with the Tsai-Wu failure theory to determine a failure criterion for the FM interface. This criterion was then used to predict the onset of ply cracking in angle-ply laminates for a range of laminate angles. Predictions for the onset of ply cracking in angle-ply laminates agreed with the test data trends.

The Need and Requirements for Validating Damage Detection Capability

DTIC Science & Technology

2011-09-01

Testing of Airborne Equipment [11], 2) Materials / Structure Certification, 3) NDE (POD) Validation Procedures, 4) Failure Mode Effects and Criticality...Analysis (FMECA), and 5) Cost Benefits Analysis [12]. Existing procedures for environmental testing of airborne equipment ensure flight...e.g. ultrasound or eddy current), damage type or failure conditions to detect, criticality of the damage state (e.g. safety of flight), likelihood of

Predictive Validity Study of the APS Writing and Reading Tests [and] Validating Placement Rules for the APS Writing Test.

ERIC Educational Resources Information Center

College of the Canyons, Valencia, CA. Office of Institutional Development.

California's College of the Canyons has used the College Board Assessment and Placement Services (APS) test to assess students' abilities in basic and college English since spring 1993. These two reports summarize data from a May 1994 study of the predictive validity of the APS writing and reading tests and a June 1994 effort to validate the cut…

Effort test failure: toward a predictive model.

PubMed

Webb, James W; Batchelor, Jennifer; Meares, Susanne; Taylor, Alan; Marsh, Nigel V

2012-01-01

Predictors of effort test failure were examined in an archival sample of 555 traumatically brain-injured (TBI) adults. Logistic regression models were used to examine whether compensation-seeking, injury-related, psychological, demographic, and cultural factors predicted effort test failure (ETF). ETF was significantly associated with compensation-seeking (OR = 3.51, 95% CI [1.25, 9.79]), low education (OR:. 83 [.74, . 94]), self-reported mood disorder (OR: 5.53 [3.10, 9.85]), exaggerated displays of behavior (OR: 5.84 [2.15, 15.84]), psychotic illness (OR: 12.86 [3.21, 51.44]), being foreign-born (OR: 5.10 [2.35, 11.06]), having sustained a workplace accident (OR: 4.60 [2.40, 8.81]), and mild traumatic brain injury severity compared with very severe traumatic brain injury severity (OR: 0.37 [0.13, 0.995]). ETF was associated with a broader range of statistical predictors than has previously been identified and the relative importance of psychological and behavioral predictors of ETF was evident in the logistic regression model. Variables that might potentially extend the model of ETF are identified for future research efforts.

Validating use of a critical thinking test for the dental admission test.

PubMed

Tsai, Tsung-Hsun

2014-04-01

The purpose of this study was to validate the use of a test to assess dental school applicants' critical thinking abilities. The intent was to include this test on the Dental Admission Test (DAT) if it was shown to enhance the DAT's validity. Correlation and regression analyses of undergraduate and dental school performance with scores on each of the tests on the DAT battery and the California Critical Thinking Skills Test (CCTST) were performed. Data were collected from 439 third- and fourth-year dental students who consented to participate and were enrolled at one of the ten accredited dental schools included in the study. These ten dental schools were from most regions of the United States. This study concluded that including the CCTST on the DAT did not significantly enhance the DAT's validity.

External validity of two nomograms for predicting distant brain failure after radiosurgery for brain metastases in a bi-institutional independent patient cohort.

PubMed

Prabhu, Roshan S; Press, Robert H; Boselli, Danielle M; Miller, Katherine R; Lankford, Scott P; McCammon, Robert J; Moeller, Benjamin J; Heinzerling, John H; Fasola, Carolina E; Patel, Kirtesh R; Asher, Anthony L; Sumrall, Ashley L; Curran, Walter J; Shu, Hui-Kuo G; Burri, Stuart H

2018-03-01

Patients treated with stereotactic radiosurgery (SRS) for brain metastases (BM) are at increased risk of distant brain failure (DBF). Two nomograms have been recently published to predict individualized risk of DBF after SRS. The goal of this study was to assess the external validity of these nomograms in an independent patient cohort. The records of consecutive patients with BM treated with SRS at Levine Cancer Institute and Emory University between 2005 and 2013 were reviewed. Three validation cohorts were generated based on the specific nomogram or recursive partitioning analysis (RPA) entry criteria: Wake Forest nomogram (n = 281), Canadian nomogram (n = 282), and Canadian RPA (n = 303) validation cohorts. Freedom from DBF at 1-year in the Wake Forest study was 30% compared with 50% in the validation cohort. The validation c-index for both the 6-month and 9-month freedom from DBF Wake Forest nomograms was 0.55, indicating poor discrimination ability, and the goodness-of-fit test for both nomograms was highly significant (p < 0.001), indicating poor calibration. The 1-year actuarial DBF in the Canadian nomogram study was 43.9% compared with 50.9% in the validation cohort. The validation c-index for the Canadian 1-year DBF nomogram was 0.56, and the goodness-of-fit test was also highly significant (p < 0.001). The validation accuracy and c-index of the Canadian RPA classification was 53% and 0.61, respectively. The Wake Forest and Canadian nomograms for predicting risk of DBF after SRS were found to have limited predictive ability in an independent bi-institutional validation cohort. These results reinforce the importance of validating predictive models in independent patient cohorts.

Studies in knowledge-based diagnosis of failures in robotic assembly

NASA Technical Reports Server (NTRS)

Lam, Raymond K.; Pollard, Nancy S.; Desai, Rajiv S.

1990-01-01

The telerobot diagnostic system (TDS) is a knowledge-based system that is being developed for identification and diagnosis of failures in the space robotic domain. The system is able to isolate the symptoms of the failure, generate failure hypotheses based on these symptoms, and test their validity at various levels by interpreting or simulating the effects of the hypotheses on results of plan execution. The implementation of the TDS is outlined. The classification of failures and the types of system models used by the TDS are discussed. A detailed example of the TDS approach to failure diagnosis is provided.

Health status in patients with coexistent COPD and heart failure: a validation and comparison between the Clinical COPD Questionnaire and the Minnesota Living with Heart Failure Questionnaire

PubMed Central

Berkhof, Farida F; Metzemaekers, Leola; Uil, Steven M; Kerstjens, Huib AM; van den Berg, Jan WK

2014-01-01

Background Chronic obstructive pulmonary disease (COPD) and heart failure (HF) are both common diseases that coexist frequently. Patients with both diseases have worse stable state health status when compared with patients with one of these diseases. In many outpatient clinics, health status is monitored routinely in COPD patients using the Clinical COPD Questionnaire (CCQ) and in HF patients with the Minnesota Living with Heart Failure Questionnaire (MLHF-Q). This study validated and compared which questionnaire, ie, the CCQ or the MLHF-Q, is suited best for patients with coexistent COPD and HF. Methods Patients with both COPD and HF and aged ≥40 years were included. Construct validity, internal consistency, test–retest reliability, and agreement were determined. The Short-Form 36 was used as the external criterion. All questionnaires were completed at baseline. The CCQ and MLHF-Q were repeated after 2 weeks, together with a global rating of change. Results Fifty-eight patients were included, of whom 50 completed the study. Construct validity was acceptable. Internal consistency was adequate for CCQ and MLHF-Q total and domain scores, with a Cronbach’s alpha ≥0.70. Reliability was adequate for MLHF-Q and CCQ total and domain scores, and intraclass correlation coefficients were 0.70–0.90, except for the CCQ symptom score (intraclass correlation coefficient 0.42). The standard error of measurement on the group level was smaller than the minimal clinical important difference for both questionnaires. However, the standard error of measurement on the individual level was larger than the minimal clinical important difference. Agreement was acceptable on the group level and limited on the individual level. Conclusion CCQ and MLHF-Q were both valid and reliable questionnaires for assessment of health status in patients with coexistent COPD and HF on the group level, and hence for research. However, in clinical practice, on the individual level, the

The Concurrent Validity of Four Tests of Metalinguistic Awareness.

ERIC Educational Resources Information Center

Day, Kaaren C.; Day, H. D.

1991-01-01

Examines the concurrent validity of four metalinguistic awareness tests (Written Language Awareness Test, Test of Early Reading Ability, Linguistic Awareness in Reading Readiness Test, and the Concepts about Print Test). Finds rather low concurrent validity coefficients which suggests that further work is needed to clarify the operations required…

Validation of Computerized Automatic Calculation of the Sequential Organ Failure Assessment Score

PubMed Central

Harrison, Andrew M.; Pickering, Brian W.; Herasevich, Vitaly

2013-01-01

Purpose. To validate the use of a computer program for the automatic calculation of the sequential organ failure assessment (SOFA) score, as compared to the gold standard of manual chart review. Materials and Methods. Adult admissions (age > 18 years) to the medical ICU with a length of stay greater than 24 hours were studied in the setting of an academic tertiary referral center. A retrospective cross-sectional analysis was performed using a derivation cohort to compare automatic calculation of the SOFA score to the gold standard of manual chart review. After critical appraisal of sources of disagreement, another analysis was performed using an independent validation cohort. Then, a prospective observational analysis was performed using an implementation of this computer program in AWARE Dashboard, which is an existing real-time patient EMR system for use in the ICU. Results. Good agreement between the manual and automatic SOFA calculations was observed for both the derivation (N=94) and validation (N=268) cohorts: 0.02 ± 2.33 and 0.29 ± 1.75 points, respectively. These results were validated in AWARE (N=60). Conclusion. This EMR-based automatic tool accurately calculates SOFA scores and can facilitate ICU decisions without the need for manual data collection. This tool can also be employed in a real-time electronic environment. PMID:23936639

Development and psychometric evaluation of the Thirst Distress Scale for patients with heart failure.

PubMed

Waldréus, Nana; Jaarsma, Tiny; van der Wal, Martje Hl; Kato, Naoko P

2018-03-01

Patients with heart failure can experience thirst distress. However, there is no instrument to measure this in patients with heart failure. The aim of the present study was to develop the Thirst Distress Scale for patients with Heart Failure (TDS-HF) and to evaluate psychometric properties of the scale. The TDS-HF was developed to measure thirst distress in patients with heart failure. Face and content validity was confirmed using expert panels including patients and healthcare professionals. Data on the TDS-HF was collected from patients with heart failure at outpatient heart failure clinics and hospitals in Sweden, the Netherlands and Japan. Psychometric properties were evaluated using data from 256 heart failure patients (age 72±11 years). Concurrent validity of the scale was assessed using a thirst intensity visual analogue scale. Patients did not have any difficulties answering the questions, and time taken to answer the questions was about five minutes. Factor analysis of the scale showed one factor. After psychometric testing, one item was deleted. For the eight item TDS-HF, a single factor explained 61% of the variance and Cronbach's alpha was 0.90. The eight item TDS-HF was significantly associated with the thirst intensity score ( r=0.55, p<0.001). Regarding test-retest reliability, the intraclass correlation coefficient was 0.88, and the weighted kappa values ranged from 0.29-0.60. The eight-item TDS-HF is valid and reliable for measuring thirst distress in patients with heart failure.

The reliability and validity of Chinese version of SF36 v2 in aging patients with chronic heart failure.

PubMed

Dong, Aishu; Chen, Sisi; Zhu, Lianlian; Shi, Lingmin; Cai, Yueli; Zeng, Jingni; Guo, Wenjian

2017-08-01

Chronic heart failure (CHF), a major public health problem worldwide, seriously limits health-related quality of life (HRQOL). How to evaluate HRQOL in older patients with CHF remains a problem. To evaluate the reliability and validity of the Chinese version of the Medical Outcomes Study Short Form version 2 (SF-36v2) in CHF patients. From September 2012 to June 2014, we assessed QOL using the SF-36v2 in 171 aging participants with CHF in four cardiology departments. Convergent and discriminant validity, factorial validity, sensitivity among different NYHA classes and between different age groups, and reliability were determined using standard measurement methods. A total of 150 participants completed a structured questionnaire including general information and the Chinese SF-36v2; 132 questionnaires were considered valid, while 21 patients refused to take part. 25 of the 50 participants invited to complete the 2-week test-retest questionnaires returned completed questionnaires. The internal consistency reliability (Cronbach's α) of the total SF-36v2 was 0.92 (range 0.74-0.93). All hypothesized item-subscale correlations showed satisfactory convergent and discriminant validity. Sensitivity was measured in different NYHA classes and age groups. Comparison of different NYHA classes showed statistical significance, but there was no significant difference between age groups. We confirmed the SF-36v2 as a valid instrument for evaluating HRQOL Chinese CHF patients. Both reliability and validity were strongly satisfactory, but there was divergence in understanding subscales such as "social functioning" because of differing cultural background. The reliability, validity, and sensitivity of SF-36v2 in aging patients with CHF were acceptable.

NASA Double Asteroid Redirection Test (Dart) Trajectory Validation and Robustness

NASA Technical Reports Server (NTRS)

Sarli, Bruno V.; Ozimek, Martin T.; Atchison, Justin A.; Englander, Jacob A.; Barbee, Brent W.

2017-01-01

The Double Asteroid Redirection Test (DART) mission will be the first to test the concept of a kinetic impactor. Several studies have been made on asteroid redirection and impact mitigation, however, to this date no mission tested the proposed concepts. An impact study on a representative body allows the measurement of the effects on the target's orbit and physical structure. With this goal, DART's objective is to verify the effectiveness of the kinetic impact concept for planetary defense. The spacecraft uses solar electric propulsion to escape Earth, flyby (138971) 2001 CB21 for impart rehearsal, and impact the secondary body of the (65803) Didymos system. This work focuses on the interplanetary trajectory design part of the mission with the validation of the baseline trajectory, performance comparison to other mission objectives, and assessment of the baseline robustness to missed thrust events. Results show a good performance of the selected trajectory for different mission objectives: latest possible escape date, maximum kinetic energy on impact, shortest possible time of flight, and use of an Earth swing-by. The baseline trajectory was shown to be robust to a missed thrust with 1% of fuel margin being enough to recover the mission for failures of more than 14 days.

NASA Double Asteroid Redirection Test (DART) Trajectory Validation and Robutness

NASA Technical Reports Server (NTRS)

Sarli, Bruno V.; Ozimek, Martin T.; Atchison, Justin A.; Englander, Jacob A.; Barbee, Brent W.

2017-01-01

The Double Asteroid Redirection Test (DART) mission will be the first to test the concept of a kinetic impactor. Several studies have been made on asteroid redirection and impact mitigation, however, to this date no mission tested the proposed concepts. An impact study on a representative body allows the measurement of the effects on the target's orbit and physical structure. With this goal, DART's objective is to verify the effectiveness of the kinetic impact concept for planetary defense. The spacecraft uses solar electric propulsion to escape Earth, fly by (138971) 2001 CB21 for impact rehearsal, and impact Didymos-B, the secondary body of the binary (65803) Didymos system. This work focuses on the heliocentric transfer design part of the mission with the validation of the baseline trajectory, performance comparison to other mission objectives, and assessment of the baseline robustness to missed thrust events. Results show a good performance of the selected trajectory for different mission objectives: latest possible escape date, maximum kinetic energy on impact, shortest possible time of flight, and use of an Earth swing-by. The baseline trajectory was shown to be robust to a missed thrust with 1% of fuel margin being enough to recover the mission for failures of more than 14 days.

Specificity rates for non-clinical, bilingual, Mexican Americans on three popular performance validity measures.

PubMed

Gasquoine, Philip G; Weimer, Amy A; Amador, Arnoldo

2017-04-01

To measure specificity as failure rates for non-clinical, bilingual, Mexican Americans on three popular performance validity measures: (a) the language format Reliable Digit Span; (b) visual-perceptual format Test of Memory Malingering; and (c) visual-perceptual format Dot Counting, using optimal/suboptimal effort cut scores developed for monolingual, English-speakers. Participants were 61 consecutive referrals, aged between 18 and 65 years, with <16 years of education who were subjectively bilingual (confirmed via formal assessment) and chose the language of assessment, Spanish or English, for the performance validity tests. Failure rates were 38% for Reliable Digit Span, 3% for the Test of Memory Malingering, and 7% for Dot Counting. For Reliable Digit Span, the failure rates for Spanish (46%) and English (31%) languages of administration did not differ significantly. Optimal/suboptimal effort cut scores derived for monolingual English-speakers can be used with Spanish/English bilinguals when using the visual-perceptual format Test of Memory Malingering and Dot Counting. The high failure rate for Reliable Digit Span suggests it should not be used as a performance validity measure with Spanish/English bilinguals, irrespective of the language of test administration, Spanish or English.

Validation studies and proficiency testing.

PubMed

Ankilam, Elke; Heinze, Petra; Kay, Simon; Van den Eede, Guy; Popping, Bert

2002-01-01

Genetically modified organisms (GMOs) entered the European food market in 1996. Current legislation demands the labeling of food products if they contain <1% GMO, as assessed for each ingredient of the product. To create confidence in the testing methods and to complement enforcement requirements, there is an urgent need for internationally validated methods, which could serve as reference methods. To date, several methods have been submitted to validation trials at an international level; approaches now exist that can be used in different circumstances and for different food matrixes. Moreover, the requirement for the formal validation of methods is clearly accepted; several national and international bodies are active in organizing studies. Further validation studies, especially on the quantitative polymerase chain reaction methods, need to be performed to cover the rising demand for new extraction methods and other background matrixes, as well as for novel GMO constructs.

40 CFR 86.1341-90 - Test cycle validation criteria.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 19 2011-07-01 2011-07-01 false Test cycle validation criteria. 86... Procedures § 86.1341-90 Test cycle validation criteria. (a) To minimize the biasing effect of the time lag... brake horsepower-hour. (c) Regression line analysis to calculate validation statistics. (1) Linear...

40 CFR 86.1341-90 - Test cycle validation criteria.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 20 2013-07-01 2013-07-01 false Test cycle validation criteria. 86... Procedures § 86.1341-90 Test cycle validation criteria. (a) To minimize the biasing effect of the time lag... brake horsepower-hour. (c) Regression line analysis to calculate validation statistics. (1) Linear...

40 CFR 86.1341-90 - Test cycle validation criteria.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 20 2012-07-01 2012-07-01 false Test cycle validation criteria. 86... Procedures § 86.1341-90 Test cycle validation criteria. (a) To minimize the biasing effect of the time lag... brake horsepower-hour. (c) Regression line analysis to calculate validation statistics. (1) Linear...

Failure Simulation Testing of the Z-1 Spacesuit Titanium Bearing Assemblies

NASA Technical Reports Server (NTRS)

de Baca, Richard C.; Juarez, Alfredo; Peralta, Stephen; Tylka, Jonathan; Rhodes, Richard

2016-01-01

The Z-2 is a candidate for NASA's next generation spacesuit, designed for a range of possible missions with enhanced mobility for spacewalks both on planetary surfaces and in microgravity. Increased mobility was accomplished through innovations in shoulder and hip joints, using a number of new bearings to allow spacesuit wearers to dip, walk, and bend with ease; all important tasks for a planetary explorer collecting samples or traveling over rough terrain. The Advanced Spacesuit Development Team of NASA Johnson Space Center requested that the NASA White Sands Test Facility (WSTF) perform a series failure simulation tests on three titanium bearing assemblies, an elemental part of the joint construction used in new spacesuit designs. This testing simulated two undetected failures within the bearings and as a result the objective of this test program was to evaluate whether a failed or failing bearing could result in ignition of the titanium race material due to friction. The first failure was an inner seal leak sufficient to pressurize the race with +99 percent oxygen. The second failure was an improperly installed or mismatched ball port that created a protrusion in the ball bearing race, partially obstructing the nominal rolling path of each ball bearing. When the spacesuit bearings are assembled, bearing balls are loaded into the assembly via a ball port. The ball port is specific and unique to each bearing assembly (matched pair). The simulated mismatched ball port is a significant source of friction, which would be caused by an assembly error. To evaluate this risk, the bearings were cycled in a simulated worst-case scenario environment, with operational loads, and potential flaw conditions. During test the amount of actuation torque required and heat generated through continuous operation were measured and the bearings were observed for sparks or burning events. This paper provides detailed descriptions of the test hardware, methodology, and results.

Content validation of the operational definitions of the nursing diagnoses of activity intolerance, excess fluid volume, and decreased cardiac output in patients with heart failure.

PubMed

de Souza, Vanessa; Zeitoun, Sandra Salloum; Lopes, Camila Takao; de Oliveira, Ana Paula Dias; Lopes, Juliana de Lima; de Barros, Alba Lucia Botura Leite

2014-06-01

To consensually validate the operational definitions of the nursing diagnoses activity intolerance, excessive fluid volume, and decreased cardiac output in patients with decompensated heart failure. Consensual validation was performed in two stages: analogy by similarity of defining characteristics, and development of operational definitions and validation with experts. A total of 38 defining characteristics were found. Operational definitions were developed and content-validated. One hundred percent of agreement was achieved among the seven experts after five rounds. "Ascites" was added in the nursing diagnosis excessive fluid volume. The consensual validation improves interpretation of human response, grounding the selection of nursing interventions and contributing to improved nursing outcomes. Support the assessment of patients with decompensated heart failure. © 2013 NANDA International.

40 CFR 86.1341-98 - Test cycle validation criteria.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 20 2012-07-01 2012-07-01 false Test cycle validation criteria. 86... Procedures § 86.1341-98 Test cycle validation criteria. Section 86.1341-98 includes text that specifies...-90 (d)(4), shall be excluded from both cycle validation and the integrated work used for emissions...

40 CFR 86.1341-98 - Test cycle validation criteria.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 20 2013-07-01 2013-07-01 false Test cycle validation criteria. 86... Procedures § 86.1341-98 Test cycle validation criteria. Section 86.1341-98 includes text that specifies...-90 (d)(4), shall be excluded from both cycle validation and the integrated work used for emissions...

40 CFR 86.1341-98 - Test cycle validation criteria.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 19 2011-07-01 2011-07-01 false Test cycle validation criteria. 86... Procedures § 86.1341-98 Test cycle validation criteria. Section 86.1341-98 includes text that specifies...-90 (d)(4), shall be excluded from both cycle validation and the integrated work used for emissions...

Students' Initial Knowledge State and Test Design: Towards a Valid and Reliable Test Instrument

ERIC Educational Resources Information Center

CoPo, Antonio Roland I.

2015-01-01

Designing a good test instrument involves specifications, test construction, validation, try-out, analysis and revision. The initial knowledge state of forty (40) tertiary students enrolled in Business Statistics course was determined and the same test instrument undergoes validation. The designed test instrument did not only reveal the baseline…

Fracture simulation of restored teeth using a continuum damage mechanics failure model.

PubMed

Li, Haiyan; Li, Jianying; Zou, Zhenmin; Fok, Alex Siu-Lun

2011-07-01

The aim of this paper is to validate the use of a finite-element (FE) based continuum damage mechanics (CDM) failure model to simulate the debonding and fracture of restored teeth. Fracture testing of plastic model teeth, with or without a standard Class-II MOD (mesial-occusal-distal) restoration, was carried out to investigate their fracture behavior. In parallel, 2D FE models of the teeth are constructed and analyzed using the commercial FE software ABAQUS. A CDM failure model, implemented into ABAQUS via the user element subroutine (UEL), is used to simulate the debonding and/or final fracture of the model teeth under a compressive load. The material parameters needed for the CDM model to simulate fracture are obtained through separate mechanical tests. The predicted results are then compared with the experimental data of the fracture tests to validate the failure model. The failure processes of the intact and restored model teeth are successfully reproduced by the simulation. However, the fracture parameters obtained from testing small specimens need to be adjusted to account for the size effect. The results indicate that the CDM model is a viable model for the prediction of debonding and fracture in dental restorations. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Microseismic Signature of Magma Failure: Testing Failure Forecast in Heterogeneous Material

NASA Astrophysics Data System (ADS)

Vasseur, J.; Lavallee, Y.; Hess, K.; Wassermann, J. M.; Dingwell, D. B.

2012-12-01

Volcanoes exhibit a range of seismic precursors prior to eruptions. This range of signals derive from different processes, which if quantified, may tell us when and how the volcano will erupt: effusively or explosively. This quantification can be performed in laboratory. Here we investigated the signals associated with the deformation and failure of single-phase silicate liquids compare to mutli-phase magmas containing pores and crystals as heterogeneities. For the past decades, magmas have been simplified as viscoelastic fluids with grossly predictable failure, following an analysis of the stress and strain rate conditions in volcanic conduits. Yet it is clear that the way magmas fail is not unique and evidences increasingly illustrate the role of heterogeneities in the process of magmatic fragmentation. In such multi-phase magmas, failure cannot be predicted using current rheological laws. Microseismicity, as detected in the laboratory by analogous Acoustic Emission (AE), can be used to monitor fracture initiation and propagation, and thus provides invaluable information to characterise the process of brittle failure underlying explosive eruptions. Tri-axial press experiments on different synthetised and natural glass samples have been performed to investigate the acoustic signature of failure. We observed that the failure of single-phase liquids occurs without much strain and is preceded by the constant nucleation, propagation and coalescence of cracks as demonstrated by the monitored AE. In contrast, the failure of multi-phase magmas depends on the applied stress and is strain dependent. The path dependence of magma failure is nonetheless accompanied by supra exponential acceleration in released AEs. Analysis of the released AEs following material Failure Forecast Method (FFM) suggests that the predicability of failure is enhanced by the presence of heterogeneities in magmas. We discuss our observations in terms of volcanic scenarios.

Temporal-varying failures of nodes in networks

NASA Astrophysics Data System (ADS)

Knight, Georgie; Cristadoro, Giampaolo; Altmann, Eduardo G.

2015-08-01

We consider networks in which random walkers are removed because of the failure of specific nodes. We interpret the rate of loss as a measure of the importance of nodes, a notion we denote as failure centrality. We show that the degree of the node is not sufficient to determine this measure and that, in a first approximation, the shortest loops through the node have to be taken into account. We propose approximations of the failure centrality which are valid for temporal-varying failures, and we dwell on the possibility of externally changing the relative importance of nodes in a given network by exploiting the interference between the loops of a node and the cycles of the temporal pattern of failures. In the limit of long failure cycles we show analytically that the escape in a node is larger than the one estimated from a stochastic failure with the same failure probability. We test our general formalism in two real-world networks (air-transportation and e-mail users) and show how communities lead to deviations from predictions for failures in hubs.

Minimizing false positive error with multiple performance validity tests: response to Bilder, Sugar, and Hellemann (2014 this issue).

PubMed

Larrabee, Glenn J

2014-01-01

Bilder, Sugar, and Hellemann (2014 this issue) contend that empirical support is lacking for use of multiple performance validity tests (PVTs) in evaluation of the individual case, differing from the conclusions of Davis and Millis (2014), and Larrabee (2014), who found no substantial increase in false positive rates using a criterion of failure of ≥ 2 PVTs and/or Symptom Validity Tests (SVTs) out of multiple tests administered. Reconsideration of data presented in Larrabee (2014) supports a criterion of ≥ 2 out of up to 7 PVTs/SVTs, as keeping false positive rates close to and in most cases below 10% in cases with bona fide neurologic, psychiatric, and developmental disorders. Strategies to minimize risk of false positive error are discussed, including (1) adjusting individual PVT cutoffs or criterion for number of PVTs failed, for examinees who have clinical histories placing them at risk for false positive identification (e.g., severe TBI, schizophrenia), (2) using the history of the individual case to rule out conditions known to result in false positive errors, (3) using normal performance in domains mimicked by PVTs to show that sufficient native ability exists for valid performance on the PVT(s) that have been failed, and (4) recognizing that as the number of PVTs/SVTs failed increases, the likelihood of valid clinical presentation decreases, with a corresponding increase in the likelihood of invalid test performance and symptom report.

Assessment of heart rate, acidosis, consciousness, oxygenation, and respiratory rate to predict noninvasive ventilation failure in hypoxemic patients.

PubMed

Duan, Jun; Han, Xiaoli; Bai, Linfu; Zhou, Lintong; Huang, Shicong

2017-02-01

To develop and validate a scale using variables easily obtained at the bedside for prediction of failure of noninvasive ventilation (NIV) in hypoxemic patients. The test cohort comprised 449 patients with hypoxemia who were receiving NIV. This cohort was used to develop a scale that considers heart rate, acidosis, consciousness, oxygenation, and respiratory rate (referred to as the HACOR scale) to predict NIV failure, defined as need for intubation after NIV intervention. The highest possible score was 25 points. To validate the scale, a separate group of 358 hypoxemic patients were enrolled in the validation cohort. The failure rate of NIV was 47.8 and 39.4% in the test and validation cohorts, respectively. In the test cohort, patients with NIV failure had higher HACOR scores at initiation and after 1, 12, 24, and 48 h of NIV than those with successful NIV. At 1 h of NIV the area under the receiver operating characteristic curve was 0.88, showing good predictive power for NIV failure. Using 5 points as the cutoff value, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy for NIV failure were 72.6, 90.2, 87.2, 78.1, and 81.8%, respectively. These results were confirmed in the validation cohort. Moreover, the diagnostic accuracy for NIV failure exceeded 80% in subgroups classified by diagnosis, age, or disease severity and also at 1, 12, 24, and 48 h of NIV. Among patients with NIV failure with a HACOR score of >5 at 1 h of NIV, hospital mortality was lower in those who received intubation at ≤12 h of NIV than in those intubated later [58/88 (66%) vs. 138/175 (79%); p = 0.03). The HACOR scale variables are easily obtained at the bedside. The scale appears to be an effective way of predicting NIV failure in hypoxemic patients. Early intubation in high-risk patients may reduce hospital mortality.

Validation test of advanced technology for IPV nickel-hydrogen flight cells: Update

NASA Technical Reports Server (NTRS)

Smithrick, John J.; Hall, Stephen W.

1992-01-01

Individual pressure vessel (IPV) nickel-hydrogen technology was advanced at NASA Lewis and under Lewis contracts with the intention of improving cycle life and performance. One advancement was to use 26 percent potassium hydroxide (KOH) electrolyte to improve cycle life. Another advancement was to modify the state-of-the-art cell design to eliminate identified failure modes. The modified design is referred to as the advanced design. A breakthrough in the low-earth-orbit (LEO) cycle life of IPV nickel-hydrogen cells has been previously reported. The cycle life of boiler plate cells containing 26 percent KOH electrolyte was about 40,000 LEO cycles compared to 3,500 cycles for cells containing 31 percent KOH. The boiler plate test results are in the process of being validated using flight hardware and real time LEO testing at the Naval Weapons Support Center (NWSC), Crane, Indiana under a NASA Lewis Contract. An advanced 125 Ah IPV nickel-hydrogen cell was designed. The primary function of the advanced cell is to store and deliver energy for long-term, LEO spacecraft missions. The new features of this design are: (1) use of 26 percent rather than 31 percent KOH electrolyte; (2) use of a patented catalyzed wall wick; (3) use of serrated-edge separators to facilitate gaseous oxygen and hydrogen flow within the cell, while still maintaining physical contact with the wall wick for electrolyte management; and (4) use of a floating rather than a fixed stack (state-of-the-art) to accommodate nickel electrode expansion due to charge/discharge cycling. The significant improvements resulting from these innovations are: extended cycle life; enhanced thermal, electrolyte, and oxygen management; and accommodation of nickel electrode expansion. The advanced cell design is in the process of being validated using real time LEO cycle life testing of NWSC, Crane, Indiana. An update of validation test results confirming this technology is presented.

The Teenage Nonviolence Test: Concurrent and Discriminant Validity.

ERIC Educational Resources Information Center

Konen, Kristopher; Mayton, Daniel M., II; Delva, Zenita; Sonnen, Melinda; Dahl, William; Montgomery, Richard

This study was designed to document the validity of the Teenage Nonviolence Test (TNT). In this study the concurrent validity of the TNT in various ways, the validity of the TNT using known groups, and the discriminant validity of the TNT by evaluating its relationships with other psychological constructs were assessed. The results showed that the…

Dynamic testing in schizophrenia: does training change the construct validity of a test?

PubMed

Wiedl, Karl H; Schöttke, Henning; Green, Michael F; Nuechterlein, Keith H

2004-01-01

Dynamic testing typically involves specific interventions for a test to assess the extent to which test performance can be modified, beyond level of baseline (static) performance. This study used a dynamic version of the Wisconsin Card Sorting Test (WCST) that is based on cognitive remediation techniques within a test-training-test procedure. From results of previous studies with schizophrenia patients, we concluded that the dynamic and static versions of the WCST should have different construct validity. This hypothesis was tested by examining the patterns of correlations with measures of executive functioning, secondary verbal memory, and verbal intelligence. Results demonstrated a specific construct validity of WCST dynamic (i.e., posttest) scores as an index of problem solving (Tower of Hanoi) and secondary verbal memory and learning (Auditory Verbal Learning Test), whereas the impact of general verbal capacity and selective attention (Verbal IQ, Stroop Test) was reduced. It is concluded that the construct validity of the test changes with dynamic administration and that this difference helps to explain why the dynamic version of the WCST predicts functional outcome better than the static version.

Failure analysis on optical fiber on swarm flight payload

NASA Astrophysics Data System (ADS)

Bourcier, Frédéric; Fratter, Isabelle; Teyssandier, Florent; Barenes, Magali; Dhenin, Jérémie; Peyriguer, Marie; Petre-Bordenave, Romain

2017-11-01

Failure analysis on optical components is usually carried-out, on standard testing devices such as optical/electronic microscopes and spectrometers, on isolated but representative samples. Such analyses are not contactless and not totally non-invasive, so they cannot be used easily on flight models. Furthermore, for late payload or satellite integration/validation phases with tight schedule issues, it could be necessary to carry out a failure analysis directly on the flight hardware, in cleanroom.

Digital Fly-By-Wire Flight Control Validation Experience

NASA Technical Reports Server (NTRS)

Szalai, K. J.; Jarvis, C. R.; Krier, G. E.; Megna, V. A.; Brock, L. D.; Odonnell, R. N.

1978-01-01

The experience gained in digital fly-by-wire technology through a flight test program being conducted by the NASA Dryden Flight Research Center in an F-8C aircraft is described. The system requirements are outlined, along with the requirements for flight qualification. The system is described, including the hardware components, the aircraft installation, and the system operation. The flight qualification experience is emphasized. The qualification process included the theoretical validation of the basic design, laboratory testing of the hardware and software elements, systems level testing, and flight testing. The most productive testing was performed on an iron bird aircraft, which used the actual electronic and hydraulic hardware and a simulation of the F-8 characteristics to provide the flight environment. The iron bird was used for sensor and system redundancy management testing, failure modes and effects testing, and stress testing in many cases with the pilot in the loop. The flight test program confirmed the quality of the validation process by achieving 50 flights without a known undetected failure and with no false alarms.

Centrifuge Modeling of Rainfall Induced Slope Failure

NASA Astrophysics Data System (ADS)

Ling, H.; Wu, M.

2006-12-01

of rainfall intensity versus duration were obtained from the test results. Such curves are extremely useful for disaster management. This study indicated feasibilities of using centrifuge modeling technique in simulating rainfall induced slope failure. The results obtained may also be used for validating numerical tools.

40 CFR 86.1341-98 - Test cycle validation criteria.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Test cycle validation criteria. 86...) Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines; Gaseous and Particulate Exhaust Test Procedures § 86.1341-98 Test cycle validation criteria. Section 86.1341-98 includes text that specifies...

Methodology for testing and validating knowledge bases

NASA Technical Reports Server (NTRS)

Krishnamurthy, C.; Padalkar, S.; Sztipanovits, J.; Purves, B. R.

1987-01-01

A test and validation toolset developed for artificial intelligence programs is described. The basic premises of this method are: (1) knowledge bases have a strongly declarative character and represent mostly structural information about different domains, (2) the conditions for integrity, consistency, and correctness can be transformed into structural properties of knowledge bases, and (3) structural information and structural properties can be uniformly represented by graphs and checked by graph algorithms. The interactive test and validation environment have been implemented on a SUN workstation.

40 CFR 86.1341-90 - Test cycle validation criteria.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Test cycle validation criteria. 86...) Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines; Gaseous and Particulate Exhaust Test Procedures § 86.1341-90 Test cycle validation criteria. (a) To minimize the biasing effect of the time lag...

The role of biaxial stresses in discriminating between meaningful and illusory composite failure theories

NASA Technical Reports Server (NTRS)

Hart-Smith, L. J.

1992-01-01

The irrelevance of most composite failure criteria to conventional fiber-polymer composites is claimed to have remained undetected primarily because the experiments that can either validate or disprove them are difficult to perform. Uniaxial tests are considered inherently incapable of validating or refuting any composite failure theory because so much of the total load is carried by the fibers aligned in the direction of the load. The Ten-Percent Rule, a simple rule-of-mixtures analysis method, is said to work well only because of this phenomenon. It is stated that failure criteria can be verified for fibrous composites only by biaxial tests, with orthogonal in-plane stresses of the same as well as different signs, because these particular states of combined stress reveal substantial differences between the predictions of laminate strength made by various theories. Three scientifically plausible failure models for fibrous composites are compared, and it is shown that only the in-plane shear test (orthogonal tension and compression) is capable of distinguishing between them. This is because most theories are 'calibrated' against the measured uniaxial tension and compression tests and any cross-plied laminate tests dominated by those same states of stress must inevitably 'confirm' the theory.

Validating a Spanish Developmental Spelling Test.

ERIC Educational Resources Information Center

Ferroli, Lou; Krajenta, Marilyn

The creation and validation of a Spanish version of an English developmental spelling test (DST) is described. An introductory section reviews related literature on the rationale for and construction of DSTs, spelling development in the early grades, and Spanish-English bilingual education. Differences between the English and Spanish test versions…

Performance and Symptom Validity Testing as a Function of Medical Board Evaluation in U.S. Military Service Members with a History of Mild Traumatic Brain Injury.

PubMed

Armistead-Jehle, Patrick; Cole, Wesley R; Stegman, Robert L

2018-02-01

The study was designed to replicate and extend pervious findings demonstrating the high rates of invalid neuropsychological testing in military service members (SMs) with a history of mild traumatic brain injury (mTBI) assessed in the context of a medical evaluation board (MEB). Two hundred thirty-one active duty SMs (61 of which were undergoing an MEB) underwent neuropsychological assessment. Performance validity (Word Memory Test) and symptom validity (MMPI-2-RF) test data were compared across those evaluated within disability (MEB) and clinical contexts. As with previous studies, there were significantly more individuals in an MEB context that failed performance (MEB = 57%, non-MEB = 31%) and symptom validity testing (MEB = 57%, non-MEB = 22%) and performance validity testing had a notable affect on cognitive test scores. Performance and symptom validity test failure rates did not vary as a function of the reason for disability evaluation when divided into behavioral versus physical health conditions. These data are consistent with past studies, and extends those studies by including symptom validity testing and investigating the effect of reason for MEB. This and previous studies demonstrate that more than 50% of SMs seen in the context of an MEB will fail performance validity tests and over-report on symptom validity measures. These results emphasize the importance of using both performance and symptom validity testing when evaluating SMs with a history of mTBI, especially if they are being seen for disability evaluations, in order to ensure the accuracy of cognitive and psychological test data. Published by Oxford University Press 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Prognostics of Power Electronics, Methods and Validation Experiments

NASA Technical Reports Server (NTRS)

Kulkarni, Chetan S.; Celaya, Jose R.; Biswas, Gautam; Goebel, Kai

2012-01-01

Abstract Failure of electronic devices is a concern for future electric aircrafts that will see an increase of electronics to drive and control safety-critical equipment throughout the aircraft. As a result, investigation of precursors to failure in electronics and prediction of remaining life of electronic components is of key importance. DC-DC power converters are power electronics systems employed typically as sourcing elements for avionics equipment. Current research efforts in prognostics for these power systems focuses on the identification of failure mechanisms and the development of accelerated aging methodologies and systems to accelerate the aging process of test devices, while continuously measuring key electrical and thermal parameters. Preliminary model-based prognostics algorithms have been developed making use of empirical degradation models and physics-inspired degradation model with focus on key components like electrolytic capacitors and power MOSFETs (metal-oxide-semiconductor-field-effect-transistor). This paper presents current results on the development of validation methods for prognostics algorithms of power electrolytic capacitors. Particularly, in the use of accelerated aging systems for algorithm validation. Validation of prognostics algorithms present difficulties in practice due to the lack of run-to-failure experiments in deployed systems. By using accelerated experiments, we circumvent this problem in order to define initial validation activities.

Could the two-minute step test be an alternative to the six-minute walk test for patients with systolic heart failure?

PubMed

Węgrzynowska-Teodorczyk, Kinga; Mozdzanowska, Dagmara; Josiak, Krystian; Siennicka, Agnieszka; Nowakowska, Katarzyna; Banasiak, Waldemar; Jankowska, Ewa A; Ponikowski, Piotr; Woźniewski, Marek

2016-08-01

The consequence of exercise intolerance for patients with heart failure is the difficulty climbing stairs. The two-minute step test is a test that reflects the activity of climbing stairs. The aim of the study design is to evaluate the applicability of the two-minute step test in an assessment of exercise tolerance in patients with heart failure and the association between the six-minute walk test and the two-minute step test. Participants in this study were 168 men with systolic heart failure (New York Heart Association (NYHA) class I-IV). In the study we used the two-minute step test, the six-minute walk test, the cardiopulmonary exercise test and isometric dynamometer armchair. Patients who performed more steps during the two-minute step test covered a longer distance during the six-minute walk test (r = 0.45). The quadriceps strength was correlated with the two-minute step test and the six-minute walk test (r = 0.61 and r = 0.48). The greater number of steps performed during the two-minute step test was associated with higher values of peak oxygen consumption (r = 0.33), ventilatory response to exercise slope (r = -0.17) and longer time of exercise during the cardiopulmonary exercise test (r = 0.34). Fatigue and leg fatigue were greater after the two-minute step test than the six-minute walk test whereas dyspnoea and blood pressure responses were similar. The two-minute step test is well tolerated by patients with heart failure and may thus be considered as an alternative for the six-minute walk test. © The European Society of Cardiology 2016.

Traceability validation of a high speed short-pulse testing method used in LED production

NASA Astrophysics Data System (ADS)

Revtova, Elena; Vuelban, Edgar Moreno; Zhao, Dongsheng; Brenkman, Jacques; Ulden, Henk

2017-12-01

Industrial processes of LED (light-emitting diode) production include LED light output performance testing. Most of them are monitored and controlled by optically, electrically and thermally measuring LEDs by high speed short-pulse measurement methods. However, these are not standardized and a lot of information is proprietary that it is impossible for third parties, such as NMIs, to trace and validate. It is known, that these techniques have traceability issue and metrological inadequacies. Often due to these, the claimed performance specifications of LEDs are overstated, which consequently results to manufacturers experiencing customers' dissatisfaction and a large percentage of failures in daily use of LEDs. In this research a traceable setup is developed to validate one of the high speed testing techniques, investigate inadequacies and work out the traceability issues. A well-characterised short square pulse of 25 ms is applied to chip-on-board (CoB) LED modules to investigate the light output and colour content. We conclude that the short-pulse method is very efficient in case a well-defined electrical current pulse is applied and the stabilization time of the device is "a priori" accurately determined. No colour shift is observed. The largest contributors to the measurement uncertainty include badly-defined current pulse and inaccurate calibration factor.

Cross-validation of the Dot Counting Test in a large sample of credible and non-credible patients referred for neuropsychological testing.

PubMed

McCaul, Courtney; Boone, Kyle B; Ermshar, Annette; Cottingham, Maria; Victor, Tara L; Ziegler, Elizabeth; Zeller, Michelle A; Wright, Matthew

2018-01-18

To cross-validate the Dot Counting Test in a large neuropsychological sample. Dot Counting Test scores were compared in credible (n = 142) and non-credible (n = 335) neuropsychology referrals. Non-credible patients scored significantly higher than credible patients on all Dot Counting Test scores. While the original E-score cut-off of ≥17 achieved excellent specificity (96.5%), it was associated with mediocre sensitivity (52.8%). However, the cut-off could be substantially lowered to ≥13.80, while still maintaining adequate specificity (≥90%), and raising sensitivity to 70.0%. Examination of non-credible subgroups revealed that Dot Counting Test sensitivity in feigned mild traumatic brain injury (mTBI) was 55.8%, whereas sensitivity was 90.6% in patients with non-credible cognitive dysfunction in the context of claimed psychosis, and 81.0% in patients with non-credible cognitive performance in depression or severe TBI. Thus, the Dot Counting Test may have a particular role in detection of non-credible cognitive symptoms in claimed psychiatric disorders. Alternative to use of the E-score, failure on ≥1 cut-offs applied to individual Dot Counting Test scores (≥6.0″ for mean grouped dot counting time, ≥10.0″ for mean ungrouped dot counting time, and ≥4 errors), occurred in 11.3% of the credible sample, while nearly two-thirds (63.6%) of the non-credible sample failed one of more of these cut-offs. An E-score cut-off of 13.80, or failure on ≥1 individual score cut-offs, resulted in few false positive identifications in credible patients, and achieved high sensitivity (64.0-70.0%), and therefore appear appropriate for use in identifying neurocognitive performance invalidity.

Determination of UAV pre-flight Checklist for flight test purpose using qualitative failure analysis

NASA Astrophysics Data System (ADS)

Hendarko; Indriyanto, T.; Syardianto; Maulana, F. A.

2018-05-01

Safety aspects are of paramount importance in flight, especially in flight test phase. Before performing any flight tests of either manned or unmanned aircraft, one should include pre-flight checklists as a required safety document in the flight test plan. This paper reports on the development of a new approach for determination of pre-flight checklists for UAV flight test based on aircraft’s failure analysis. The Lapan’s LSA (Light Surveillance Aircraft) is used as a study case, assuming this aircraft has been transformed into the unmanned version. Failure analysis is performed on LSA using fault tree analysis (FTA) method. Analysis is focused on propulsion system and flight control system, which fail of these systems will lead to catastrophic events. Pre-flight checklist of the UAV is then constructed based on the basic causes obtained from failure analysis.

A new casemix adjustment index for hospital mortality among patients with congestive heart failure.

PubMed

Polanczyk, C A; Rohde, L E; Philbin, E A; Di Salvo, T G

1998-10-01

Comparative analysis of hospital outcomes requires reliable adjustment for casemix. Although congestive heart failure is one of the most common indications for hospitalization, congestive heart failure casemix adjustment has not been widely studied. The purposes of this study were (1) to describe and validate a new congestive heart failure-specific casemix adjustment index to predict in-hospital mortality and (2) to compare its performance to the Charlson comorbidity index. Data from all 4,608 admissions to the Massachusetts General Hospital from January 1990 to July 1996 with a principal ICD-9-CM discharge diagnosis of congestive heart failure were evaluated. Massachusetts General Hospital patients were randomly divided in a derivation and a validation set. By logistic regression, odds ratios for in-hospital death were computed and weights were assigned to construct a new predictive index in the derivation set. The performance of the index was tested in an internal Massachusetts General Hospital validation set and in a non-Massachusetts General Hospital external validation set incorporating data from all 1995 New York state hospital discharges with a primary discharge diagnosis of congestive heart failure. Overall in-hospital mortality was 6.4%. Based on the new index, patients were assigned to six categories with incrementally increasing hospital mortality rates ranging from 0.5% to 31%. By logistic regression, "c" statistics of the congestive heart failure-specific index (0.83 and 0.78, derivation and validation set) were significantly superior to the Charlson index (0.66). Similar incrementally increasing hospital mortality rates were observed in the New York database with the congestive heart failure-specific index ("c" statistics 0.75). In an administrative database, this congestive heart failure-specific index may be a more adequate casemix adjustment tool to predict hospital mortality in patients hospitalized for congestive heart failure.

Development of wheelchair caster testing equipment and preliminary testing of caster models

PubMed Central

Mhatre, Anand; Ott, Joseph

2017-01-01

Background Because of the adverse environmental conditions present in less-resourced environments (LREs), the World Health Organization (WHO) has recommended that specialised wheelchair test methods may need to be developed to support product quality standards in these environments. A group of experts identified caster test methods as a high priority because of their common failure in LREs, and the insufficiency of existing test methods described in the International Organization for Standardization (ISO) Wheelchair Testing Standards (ISO 7176). Objectives To develop and demonstrate the feasibility of a caster system test method. Method Background literature and expert opinions were collected to identify existing caster test methods, caster failures common in LREs and environmental conditions present in LREs. Several conceptual designs for the caster testing method were developed, and through an iterative process using expert feedback, a final concept and a design were developed and a prototype was fabricated. Feasibility tests were conducted by testing a series of caster systems from wheelchairs used in LREs, and failure modes were recorded and compared to anecdotal reports about field failures. Results The new caster testing system was developed and it provides the flexibility to expose caster systems to typical conditions in LREs. Caster failures such as stem bolt fractures, fork fractures, bearing failures and tire cracking occurred during testing trials and are consistent with field failures. Conclusion The new caster test system has the capability to incorporate necessary test factors that degrade caster quality in LREs. Future work includes developing and validating a testing protocol that results in failure modes common during wheelchair use in LRE. PMID:29062762

Failure modes and effects criticality analysis and accelerated life testing of LEDs for medical applications

NASA Astrophysics Data System (ADS)

Sawant, M.; Christou, A.

2012-12-01

While use of LEDs in Fiber Optics and lighting applications is common, their use in medical diagnostic applications is not very extensive. Since the precise value of light intensity will be used to interpret patient results, understanding failure modes [1-4] is very important. We used the Failure Modes and Effects Criticality Analysis (FMECA) tool to identify the critical failure modes of the LEDs. FMECA involves identification of various failure modes, their effects on the system (LED optical output in this context), their frequency of occurrence, severity and the criticality of the failure modes. The competing failure modes/mechanisms were degradation of: active layer (where electron-hole recombination occurs to emit light), electrodes (provides electrical contact to the semiconductor chip), Indium Tin Oxide (ITO) surface layer (used to improve current spreading and light extraction), plastic encapsulation (protective polymer layer) and packaging failures (bond wires, heat sink separation). A FMECA table is constructed and the criticality is calculated by estimating the failure effect probability (β), failure mode ratio (α), failure rate (λ) and the operating time. Once the critical failure modes were identified, the next steps were generation of prior time to failure distribution and comparing with our accelerated life test data. To generate the prior distributions, data and results from previous investigations were utilized [5-33] where reliability test results of similar LEDs were reported. From the graphs or tabular data, we extracted the time required for the optical power output to reach 80% of its initial value. This is our failure criterion for the medical diagnostic application. Analysis of published data for different LED materials (AlGaInP, GaN, AlGaAs), the Semiconductor Structures (DH, MQW) and the mode of testing (DC, Pulsed) was carried out. The data was categorized according to the materials system and LED structure such as AlGaInP-DH-DC, Al

Validation of a diabetes numeracy test in Arabic.

PubMed

Alghodaier, Hussah; Jradi, Hoda; Mohammad, Najwa Samantha; Bawazir, Amen

2017-01-01

The prevalence of diabetes Mellitus in Saudi Arabia is 24%, ranking it among the top ten Worldwide. Diabetes education focuses on self-management and relies on numeracy skills. Poor numeracy may go unrecognized and it is important to have an assessment tool in Arabic to measure such a skill in diabetes care. To validate a 15-item Diabetes Numeracy Test (DNT-15) in the Arabic Language as a tool to assess the numeracy skills of patients with diabetes and to test its properties among Saudi patients with diabetes. A 15-question Arabic-language test to assess diabetes numeracy among patients with diabetes on the basis of the diabetes numeracy test (DNT-15) was validated among a sample Arabic speaking Saudi patients with diabetes. Data collection included patients' demographics, long-term glycemic control, diabetes type, duration, co-morbidities, and diabetes related knowledge questions. Internal reliability was assessed using Kuder-Richardson Formula 20 (KR-20). The average score of Arabic DNT-15 was 53.3% and took an average of 30 minutes to complete. The scores significantly correlated with education, income, HbA1c, and diabetes knowledge (p<0.05). Content Validity Ratio (CVR) of 0.75 and Content Validity Index (CVI) of 0.89 supported good content validity. The Arabic DNT-15 also had good internal reliability (KR20 = 0.90). Patients with diabetes need numeracy skills to manage their disease. Level of education does not reflect level of numeracy, and low numeracy skills might be unnoticed by health care providers. The Arabic DNT-15 is a valid and reliable scale to identify Arabic speaking patients with difficulties in certain diabetes-related numeracy skills.

Validation of the Sport Competition Anxiety Test.

ERIC Educational Resources Information Center

Cheatham, T.; Rosentswieg, J.

1982-01-01

Fifteen female varsity softball coaches were administered the Sport Competition Anxiety Test prior to competition. Their heart rates, continuously monitored by tilemetry, did not relate significantly to the anxiety test data. The test does not appear to be a valid measure of trait anxiety for women softball coaches. (Author/PN)

Educational testing validity and reliability in pharmacy and medical education literature.

PubMed

Hoover, Matthew J; Jung, Rose; Jacobs, David M; Peeters, Michael J

2013-12-16

To evaluate and compare the reliability and validity of educational testing reported in pharmacy education journals to medical education literature. Descriptions of validity evidence sources (content, construct, criterion, and reliability) were extracted from articles that reported educational testing of learners' knowledge, skills, and/or abilities. Using educational testing, the findings of 108 pharmacy education articles were compared to the findings of 198 medical education articles. For pharmacy educational testing, 14 articles (13%) reported more than 1 validity evidence source while 83 articles (77%) reported 1 validity evidence source and 11 articles (10%) did not have evidence. Among validity evidence sources, content validity was reported most frequently. Compared with pharmacy education literature, more medical education articles reported both validity and reliability (59%; p<0.001). While there were more scholarship of teaching and learning (SoTL) articles in pharmacy education compared to medical education, validity, and reliability reporting were limited in the pharmacy education literature.

Construct Validation of the Fairy Tale Test--Standardization Data.

ERIC Educational Resources Information Center

Coulacoglou, Carina

2002-01-01

Studied the construct validity of the Fairy Tale Test (C. Coulacoglu, 1993), a personality projective test for children, in a sample of 800 Greek children aged 8, 10, and 12. Factor analysis led to identification of eight primary factors, and correlations with other measures provide construct validity evidence. (SLD)

Validating Test Score Meaning and Defending Test Score Use: Different Aims, Different Methods

ERIC Educational Resources Information Center

Cizek, Gregory J.

2016-01-01

Advances in validity theory and alacrity in validation practice have suffered because the term "validity" has been used to refer to two incompatible concerns: (1) the degree of support for specified interpretations of test scores (i.e. intended score meaning) and (2) the degree of support for specified applications (i.e. intended test…

Failure analysis of electronic parts: Laboratory methods. [for destructive and nondestructive testing

NASA Technical Reports Server (NTRS)

Anstead, R. J. (Editor); Goldberg, E. (Editor)

1975-01-01

Failure analysis test methods are presented for use in analyzing candidate electronic parts and in improving future design reliability. Each test is classified as nondestructive, semidestructive, or destructive. The effects upon applicable part types (i.e. integrated circuit, transitor) are discussed. Methodology is given for performing the following: immersion tests, radio graphic tests, dewpoint tests, gas ambient analysis, cross sectioning, and ultraviolet examination.

Development and testing of an algorithm to detect implantable cardioverter-defibrillator lead failure.

PubMed

Gunderson, Bruce D; Gillberg, Jeffrey M; Wood, Mark A; Vijayaraman, Pugazhendhi; Shepard, Richard K; Ellenbogen, Kenneth A

2006-02-01

Implantable cardioverter-defibrillator (ICD) lead failures often present as inappropriate shock therapy. An algorithm that can reliably discriminate between ventricular tachyarrhythmias and noise due to lead failure may prevent patient discomfort and anxiety and avoid device-induced proarrhythmia by preventing inappropriate ICD shocks. The goal of this analysis was to test an ICD tachycardia detection algorithm that differentiates noise due to lead failure from ventricular tachyarrhythmias. We tested an algorithm that uses a measure of the ventricular intracardiac electrogram baseline to discriminate the sinus rhythm isoelectric line from the right ventricular coil-can (i.e., far-field) electrogram during oversensing of noise caused by a lead failure. The baseline measure was defined as the product of the sum (mV) and standard deviation (mV) of the voltage samples for a 188-ms window centered on each sensed electrogram. If the minimum baseline measure of the last 12 beats was <0.35 mV-mV, then the detected rhythm was considered noise due to a lead failure. The first ICD-detected episode of lead failure and inappropriate detection from 24 ICD patients with a pace/sense lead failure and all ventricular arrhythmias from 56 ICD patients without a lead failure were selected. The stored data were analyzed to determine the sensitivity and specificity of the algorithm to detect lead failures. The minimum baseline measure for the 24 lead failure episodes (0.28 +/- 0.34 mV-mV) was smaller than the 135 ventricular tachycardia (40.8 +/- 43.0 mV-mV, P <.0001) and 55 ventricular fibrillation episodes (19.1 +/- 22.8 mV-mV, P <.05). A minimum baseline <0.35 mV-mV threshold had a sensitivity of 83% (20/24) with a 100% (190/190) specificity. A baseline measure of the far-field electrogram had a high sensitivity and specificity to detect lead failure noise compared with ventricular tachycardia or fibrillation.

Experimental validation of clock synchronization algorithms

NASA Technical Reports Server (NTRS)

Palumbo, Daniel L.; Graham, R. Lynn

1992-01-01

The objective of this work is to validate mathematically derived clock synchronization theories and their associated algorithms through experiment. Two theories are considered, the Interactive Convergence Clock Synchronization Algorithm and the Midpoint Algorithm. Special clock circuitry was designed and built so that several operating conditions and failure modes (including malicious failures) could be tested. Both theories are shown to predict conservative upper bounds (i.e., measured values of clock skew were always less than the theory prediction). Insight gained during experimentation led to alternative derivations of the theories. These new theories accurately predict the behavior of the clock system. It is found that a 100 percent penalty is paid to tolerate worst-case failures. It is also shown that under optimal conditions (with minimum error and no failures) the clock skew can be as much as three clock ticks. Clock skew grows to six clock ticks when failures are present. Finally, it is concluded that one cannot rely solely on test procedures or theoretical analysis to predict worst-case conditions.

WEC-SIM Validation Testing Plan FY14 Q4.

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

Ruehl, Kelley Michelle

2016-02-01

The WEC-Sim project is currently on track, having met both the SNL and NREL FY14 Milestones, as shown in Table 1 and Table 2. This is also reflected in the Gantt chart uploaded to the WEC-Sim SharePoint site in the FY14 Q4 Deliverables folder. The work completed in FY14 includes code verification through code-to-code comparison (FY14 Q1 and Q2), preliminary code validation through comparison to experimental data (FY14 Q2 and Q3), presentation and publication of the WEC-Sim project at OMAE 2014 [1], [2], [3] and GMREC/METS 2014 [4] (FY14 Q3), WEC-Sim code development and public open-source release (FY14 Q3), andmore » development of a preliminary WEC-Sim validation test plan (FY14 Q4). This report presents the preliminary Validation Testing Plan developed in FY14 Q4. The validation test effort started in FY14 Q4 and will go on through FY15. Thus far the team has developed a device selection method, selected a device, and placed a contract with the testing facility, established several collaborations including industry contacts, and have working ideas on the testing details such as scaling, device design, and test conditions.« less

Extended version of the "Sniffin' Sticks" identification test: test-retest reliability and validity.

PubMed

Sorokowska, A; Albrecht, E; Haehner, A; Hummel, T

2015-03-30

The extended, 32-item version of the Sniffin' Sticks identification test was developed in order to create a precise tool enabling repeated, longitudinal testing of individual olfactory subfunctions. Odors of the previous test version had to be changed for technical reasons, and the odor identification test needed re-investigation in terms of reliability, validity, and normative values. In our study we investigated olfactory abilities of a group of 100 patients with olfactory dysfunction and 100 controls. We reconfirmed the high test-retest reliability of the extended version of the Sniffin' Sticks identification test and high correlations between the new and the original part of this tool. In addition, we confirmed the validity of the test as it discriminated clearly between controls and patients with olfactory loss. The additional set of 16 odor identification sticks can be either included in the current olfactory test, thus creating a more detailed diagnosis tool, or it can be used separately, enabling to follow olfactory function over time. Additionally, the normative values presented in our paper might provide useful guidelines for interpretation of the extended identification test results. The revised version of the Sniffin' Sticks 32-item odor identification test is a reliable and valid tool for the assessment of olfactory function. Copyright © 2015 Elsevier B.V. All rights reserved.

Failure analysis of energy storage spring in automobile composite brake chamber

NASA Astrophysics Data System (ADS)

Luo, Zai; Wei, Qing; Hu, Xiaofeng

2015-02-01

This paper set energy storage spring of parking brake cavity, part of automobile composite brake chamber, as the research object. And constructed the fault tree model of energy storage spring which caused parking brake failure based on the fault tree analysis method. Next, the parking brake failure model of energy storage spring was established by analyzing the working principle of composite brake chamber. Finally, the data of working load and the push rod stroke measured by comprehensive test-bed valve was used to validate the failure model above. The experimental result shows that the failure model can distinguish whether the energy storage spring is faulted.

Real-time sensor data validation

NASA Technical Reports Server (NTRS)

Bickmore, Timothy W.

1994-01-01

This report describes the status of an on-going effort to develop software capable of detecting sensor failures on rocket engines in real time. This software could be used in a rocket engine controller to prevent the erroneous shutdown of an engine due to sensor failures which would otherwise be interpreted as engine failures by the control software. The approach taken combines analytical redundancy with Bayesian belief networks to provide a solution which has well defined real-time characteristics and well-defined error rates. Analytical redundancy is a technique in which a sensor's value is predicted by using values from other sensors and known or empirically derived mathematical relations. A set of sensors and a set of relations among them form a network of cross-checks which can be used to periodically validate all of the sensors in the network. Bayesian belief networks provide a method of determining if each of the sensors in the network is valid, given the results of the cross-checks. This approach has been successfully demonstrated on the Technology Test Bed Engine at the NASA Marshall Space Flight Center. Current efforts are focused on extending the system to provide a validation capability for 100 sensors on the Space Shuttle Main Engine.

Validity and reliability of the Hexoskin® wearable biometric vest during maximal aerobic power testing in elite cyclists.

PubMed

Elliot, Catherine A; Hamlin, Michael J; Lizamore, Catherine A

2017-07-28

The purpose of this study was to investigate the validity and reliability of the Hexoskin® vest for measuring respiration and heart rate (HR) in elite cyclists during a progressive test to exhaustion. Ten male elite cyclists (age 28.8 ± 12.5 yr, height 179.3 ± 6.0 cm, weight 73.2 ± 9.1 kg, V˙ O2max 60.7 ± 7.8 ml.kg.min mean ± SD) conducted a maximal aerobic cycle ergometer test using a ramped protocol (starting at 100W with 25W increments each min to failure) during two separate occasions over a 3-4 day period. Compared to the criterion measure (Metamax 3B) the Hexoskin® vest showed mainly small typical errors (1.3-6.2%) for HR and breathing frequency (f), but larger typical errors (9.5-19.6%) for minute ventilation (V˙E) during the progressive test to exhaustion. The typical error indicating the reliability of the Hexoskin® vest at moderate intensity exercise between tests was small for HR (2.6-2.9%) and f (2.5-3.2%) but slightly larger for V˙E (5.3-7.9%). We conclude that the Hexoskin® vest is sufficiently valid and reliable for measurements of HR and f in elite athletes during high intensity cycling but the calculated V˙E value the Hexoskin® vest produces during such exercise should be used with caution due to the lower validity and reliability of this variable.

Comprehensive analysis of cochlear implant failure: usefulness of clinical symptom-based algorithm combined with in situ integrity testing.

PubMed

Yamazaki, Hiroshi; O'Leary, Stephen; Moran, Michelle; Briggs, Robert

2014-04-01

Accurate diagnosis of cochlear implant failures is important for management; however, appropriate strategies to assess possible device failures are not always clear. The purpose of this study is to understand correlation between causes of device failure and the presenting clinical symptoms as well as results of in situ integrity testing and to propose effective strategies for diagnosis of device failure. Retrospective case review. Cochlear implant center at a tertiary referral hospital. Twenty-seven cases with suspected device failure of Cochlear Nucleus systems (excluding CI512 failures) on the basis of deterioration in auditory perception from January 2000 to September 2012 in the Melbourne cochlear implant clinic. Clinical presentations and types of abnormalities on in situ integrity testing were compared with modes of device failure detected by returned device analysis. Sudden deterioration in auditory perception was always observed in cases with "critical damage": either fracture of the integrated circuit or most or all of the electrode wires. Subacute or gradually progressive deterioration in auditory perception was significantly associated with a more limited number of broken electrode wires. Cochlear implant mediated auditory and nonauditory symptoms were significantly associated with an insulation problem. An algorithm based on the time course of deterioration in auditory perception and cochlear implant-mediated auditory and nonauditory symptoms was developed on the basis of these retrospective analyses, to help predict the mode of device failure. In situ integrity testing, which included close monitoring of device function in routine programming sessions as well as repeating the manufacturer's integrity test battery, was sensitive enough to detect malfunction in all suspected device failures, and each mode of device failure showed a characteristic abnormality on in situ integrity testing. Our clinical manifestation-based algorithm combined with in situ

Herth hope index: psychometric testing of the Chinese version.

PubMed

Chan, Keung Sum; Li, Ho Cheung William; Chan, Sally Wai-Chi; Lopez, Violeta

2012-09-01

This article is a report on psychometric testing of the Chinese version of the herth hope index. The availability of a valid and reliable instrument that accurately measures the level of hope in patients with heart failure is crucial before any hope-enhancing interventions can be appropriately planned and evaluated. There is no such instrument for Chinese people. A test-retest, within-subjects design was used. A purposive sample of 120 Hong Kong Chinese patients with heart failure between the ages of 60 and 80 years admitted to two medical wards was recruited during an 8-month period in 2009. Participants were asked to respond to the Chinese version of the herth hope index, Hamilton depression rating scale and Rosenberg's self-esteem scale. The internal consistency, content validity and construct validity and test-retest reliability of the Chinese version of the herth hope index were assessed. The newly translated scale demonstrated adequate internal consistency, good content validity and appropriate convergent and discriminant validity. Confirmatory factor analysis added further evidence of the construct validity of the scale. Results suggest that the newly translated scale can be used as a self-report assessment tool in assessing the level of hope in Hong Kong Chinese patients with heart failure. © 2011 Blackwell Publishing Ltd.

The Hyper-X Flight Systems Validation Program

NASA Technical Reports Server (NTRS)

Redifer, Matthew; Lin, Yohan; Bessent, Courtney Amos; Barklow, Carole

2007-01-01

For the Hyper-X/X-43A program, the development of a comprehensive validation test plan played an integral part in the success of the mission. The goal was to demonstrate hypersonic propulsion technologies by flight testing an airframe-integrated scramjet engine. Preparation for flight involved both verification and validation testing. By definition, verification is the process of assuring that the product meets design requirements; whereas validation is the process of assuring that the design meets mission requirements for the intended environment. This report presents an overview of the program with emphasis on the validation efforts. It includes topics such as hardware-in-the-loop, failure modes and effects, aircraft-in-the-loop, plugs-out, power characterization, antenna pattern, integration, combined systems, captive carry, and flight testing. Where applicable, test results are also discussed. The report provides a brief description of the flight systems onboard the X-43A research vehicle and an introduction to the ground support equipment required to execute the validation plan. The intent is to provide validation concepts that are applicable to current, follow-on, and next generation vehicles that share the hybrid spacecraft and aircraft characteristics of the Hyper-X vehicle.

Application of a truncated normal failure distribution in reliability testing

NASA Technical Reports Server (NTRS)

Groves, C., Jr.

1968-01-01

Statistical truncated normal distribution function is applied as a time-to-failure distribution function in equipment reliability estimations. Age-dependent characteristics of the truncated function provide a basis for formulating a system of high-reliability testing that effectively merges statistical, engineering, and cost considerations.

Coverage of the Test of Memory Malingering, Victoria Symptom Validity Test, and Word Memory Test on the Internet: is test security threatened?

PubMed

Bauer, Lyndsey; McCaffrey, Robert J

2006-01-01

In forensic neuropsychological settings, maintaining test security has become critically important, especially in regard to symptom validity tests (SVTs). Coaching, which can entail providing patients or litigants with information about the cognitive sequelae of head injury, or teaching them test-taking strategies to avoid detection of symptom dissimulation has been examined experimentally in many research studies. Emerging evidence supports that coaching strategies affect psychological and neuropsychological test performance to differing degrees depending on the coaching paradigm and the tests administered. The present study sought to examine Internet coverage of SVTs because it is potentially another source of coaching, or information that is readily available. Google searches were performed on the Test of Memory Malingering, the Victoria Symptom Validity Test, and the Word Memory Test. Results indicated that there is a variable amount of information available about each test that could threaten test security and validity should inappropriately interested parties find it. Steps that could be taken to improve this situation and limitations to this exploration are discussed.

Development and Validation of Diagnostic Economics Test for Secondary Schools

ERIC Educational Resources Information Center

Eleje, Lydia I.; Esomonu, Nkechi P. M.; Agu, Ngozi N.; Okoye, Romy O.; Obasi, Emma; Onah, Frederick E.

2016-01-01

A diagnostic test in economics to aid the teachers determine student's specific weak content areas was developed and validated. Five research questions guided the study. Preliminary validation was done by two experienced teachers in the content area of secondary economics and two experts in test construction. The pilot testing was conducted for…

Failure Engineering Study and Accelerated Stress Test Results for the Mars Global Surveyor Spacecraft's Power Shunt Assemblies

NASA Technical Reports Server (NTRS)

Gibbel, Mark; Larson, Timothy

2000-01-01

An Engineering-of-Failure approach to designing and executing an accelerated product qualification test was performed to support a risk assessment of a "work-around" necessitated by an on-orbit failure of another piece of hardware on the Mars Global Surveyor spacecraft. The proposed work-around involved exceeding the previous qualification experience both in terms of extreme cold exposure level and in terms of demonstrated low cycle fatigue life for the power shunt assemblies. An analysis was performed to identify potential failure sites, modes and associated failure mechanisms consistent with the new use conditions. A test was then designed and executed which accelerated the failure mechanisms identified by analysis. Verification of the resulting failure mechanism concluded the effort.

10 CFR 26.139 - Reporting initial validity and drug test results.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false Reporting initial validity and drug test results. 26.139... § 26.139 Reporting initial validity and drug test results. (a) The licensee testing facility shall... permitted under § 26.75(h), positive test results from initial drug tests at the licensee testing facility...

10 CFR 26.139 - Reporting initial validity and drug test results.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Reporting initial validity and drug test results. 26.139... § 26.139 Reporting initial validity and drug test results. (a) The licensee testing facility shall... permitted under § 26.75(h), positive test results from initial drug tests at the licensee testing facility...

Validation of Clinical Testing for Warfarin Sensitivity

PubMed Central

Langley, Michael R.; Booker, Jessica K.; Evans, James P.; McLeod, Howard L.; Weck, Karen E.

2009-01-01

Responses to warfarin (Coumadin) anticoagulation therapy are affected by genetic variability in both the CYP2C9 and VKORC1 genes. Validation of pharmacogenetic testing for warfarin responses includes demonstration of analytical validity of testing platforms and of the clinical validity of testing. We compared four platforms for determining the relevant single nucleotide polymorphisms (SNPs) in both CYP2C9 and VKORC1 that are associated with warfarin sensitivity (Third Wave Invader Plus, ParagonDx/Cepheid Smart Cycler, Idaho Technology LightCycler, and AutoGenomics Infiniti). Each method was examined for accuracy, cost, and turnaround time. All genotyping methods demonstrated greater than 95% accuracy for identifying the relevant SNPs (CYP2C9 *2 and *3; VKORC1 −1639 or 1173). The ParagonDx and Idaho Technology assays had the shortest turnaround and hands-on times. The Third Wave assay was readily scalable to higher test volumes but had the longest hands-on time. The AutoGenomics assay interrogated the largest number of SNPs but had the longest turnaround time. Four published warfarin-dosing algorithms (Washington University, UCSF, Louisville, and Newcastle) were compared for accuracy for predicting warfarin dose in a retrospective analysis of a local patient population on long-term, stable warfarin therapy. The predicted doses from both the Washington University and UCSF algorithms demonstrated the best correlation with actual warfarin doses. PMID:19324988

The Need, Development, and Validation of the Innovation Test Instrument

ERIC Educational Resources Information Center

Wheadon, Jacob; Wright, Geoff A.; West, Richard E.; Skaggs, Paul

2017-01-01

This study discusses the need, development, and validation of the Innovation Test Instrument (ITI). This article outlines how the researchers identified the content domain of the assessment and created test items. Then, it describes initial validation testing of the instrument. The findings suggest that the ITI is a good first step in creating an…

Validation of the Simple Shoulder Test in a Portuguese-Brazilian population. Is the latent variable structure and validation of the Simple Shoulder Test Stable across cultures?

PubMed

Neto, Jose Osni Bruggemann; Gesser, Rafael Lehmkuhl; Steglich, Valdir; Bonilauri Ferreira, Ana Paula; Gandhi, Mihir; Vissoci, João Ricardo Nickenig; Pietrobon, Ricardo

2013-01-01

The validation of widely used scales facilitates the comparison across international patient samples. The objective of this study was to translate, culturally adapt and validate the Simple Shoulder Test into Brazilian Portuguese. Also we test the stability of factor analysis across different cultures. The objective of this study was to translate, culturally adapt and validate the Simple Shoulder Test into Brazilian Portuguese. Also we test the stability of factor analysis across different cultures. The Simple Shoulder Test was translated from English into Brazilian Portuguese, translated back into English, and evaluated for accuracy by an expert committee. It was then administered to 100 patients with shoulder conditions. Psychometric properties were analyzed including factor analysis, internal reliability, test-retest reliability at seven days, and construct validity in relation to the Short Form 36 health survey (SF-36). Factor analysis demonstrated a three factor solution. Cronbach's alpha was 0.82. Test-retest reliability index as measured by intra-class correlation coefficient (ICC) was 0.84. Associations were observed in the hypothesized direction with all subscales of SF-36 questionnaire. The Simple Shoulder Test translation and cultural adaptation to Brazilian-Portuguese demonstrated adequate factor structure, internal reliability, and validity, ultimately allowing for its use in the comparison with international patient samples.

Validation of the Simple Shoulder Test in a Portuguese-Brazilian Population. Is the Latent Variable Structure and Validation of the Simple Shoulder Test Stable across Cultures?

PubMed Central

Neto, Jose Osni Bruggemann; Gesser, Rafael Lehmkuhl; Steglich, Valdir; Bonilauri Ferreira, Ana Paula; Gandhi, Mihir; Vissoci, João Ricardo Nickenig; Pietrobon, Ricardo

2013-01-01

Background The validation of widely used scales facilitates the comparison across international patient samples. The objective of this study was to translate, culturally adapt and validate the Simple Shoulder Test into Brazilian Portuguese. Also we test the stability of factor analysis across different cultures. Objective The objective of this study was to translate, culturally adapt and validate the Simple Shoulder Test into Brazilian Portuguese. Also we test the stability of factor analysis across different cultures. Methods The Simple Shoulder Test was translated from English into Brazilian Portuguese, translated back into English, and evaluated for accuracy by an expert committee. It was then administered to 100 patients with shoulder conditions. Psychometric properties were analyzed including factor analysis, internal reliability, test-retest reliability at seven days, and construct validity in relation to the Short Form 36 health survey (SF-36). Results Factor analysis demonstrated a three factor solution. Cronbach’s alpha was 0.82. Test-retest reliability index as measured by intra-class correlation coefficient (ICC) was 0.84. Associations were observed in the hypothesized direction with all subscales of SF-36 questionnaire. Conclusion The Simple Shoulder Test translation and cultural adaptation to Brazilian-Portuguese demonstrated adequate factor structure, internal reliability, and validity, ultimately allowing for its use in the comparison with international patient samples. PMID:23675436

Voltage stress effects on microcircuit accelerated life test failure rates

NASA Technical Reports Server (NTRS)

Johnson, G. M.

1976-01-01

The applicability of Arrhenius and Eyring reaction rate models for describing microcircuit aging characteristics as a function of junction temperature and applied voltage was evaluated. The results of a matrix of accelerated life tests with a single metal oxide semiconductor microcircuit operated at six different combinations of temperature and voltage were used to evaluate the models. A total of 450 devices from two different lots were tested at ambient temperatures between 200 C and 250 C and applied voltages between 5 Vdc and 15 Vdc. A statistical analysis of the surface related failure data resulted in bimodal failure distributions comprising two lognormal distributions; a 'freak' distribution observed early in time, and a 'main' distribution observed later in time. The Arrhenius model was shown to provide a good description of device aging as a function of temperature at a fixed voltage. The Eyring model also appeared to provide a reasonable description of main distribution device aging as a function of temperature and voltage. Circuit diagrams are shown.

Construction of Valid and Reliable Test for Assessment of Students

ERIC Educational Resources Information Center

Osadebe, P. U.

2015-01-01

The study was carried out to construct a valid and reliable test in Economics for secondary school students. Two research questions were drawn to guide the establishment of validity and reliability for the Economics Achievement Test (EAT). It is a multiple choice objective test of five options with 100 items. A sample of 1000 students was randomly…

Validity and Reliability of the Arabic Token Test for Children

ERIC Educational Resources Information Center

Alkhamra, Rana A.; Al-Jazi, Aya B.

2016-01-01

Background: The Token Test for Children (2nd edition) (TTFC) is a measure for assessing receptive language. In this study we describe the translation process, validity and reliability of the Arabic Token Test for Children (A-TTFC). Aims: The aim of this study is to translate, validate and establish the reliability of the Arabic Token Test for…

Conceptualizing Essay Tests' Reliability and Validity: From Research to Theory

ERIC Educational Resources Information Center

Badjadi, Nour El Imane

2013-01-01

The current paper on writing assessment surveys the literature on the reliability and validity of essay tests. The paper aims to examine the two concepts in relationship with essay testing as well as to provide a snapshot of the current understandings of the reliability and validity of essay tests as drawn in recent research studies. Bearing in…

Is the Sørensen test valid to assess muscle fatigue of the trunk extensor muscles?

PubMed

Demoulin, Christophe; Boyer, Mathieu; Duchateau, Jacques; Grosdent, Stéphanie; Jidovtseff, Boris; Crielaard, Jean-Michel; Vanderthommen, Marc

2016-01-01

Very few studies have quantified the degree of fatigue characterized by the decline in the maximal voluntary contraction (MVC) force of the trunk extensors induced by the widely used Sørensen test. Measure the degree of fatigue of the trunk extensor muscles induced by the Sørensen test. Eighty young healthy subjects were randomly divided into a control group (CG) and an experimental group (EG), each including 50% of the two genders. The EG performed an isometric MVC of the trunk extensors (pre-fatigue test) followed by the Sørensen test, the latter being immediately followed by another MVC (post-fatigue test). The CG performed only the pre- and post-fatigue tests without any exertion in between. The comparison of the pre- and post-fatigue tests revealed a significant (P< 0.05) decrease in MVC force normalized by body mass (-13%) in the EG, whereas a small increase occurred in the CG (+2.7%, P= 0.001). This study shows that the Sørensen test performed until failure in a young healthy population results in a reduced ability of the trunk extensor muscles to generate maximal force, and indicates that this test is valid for the assessment of fatigue in trunk extensor muscles.

Using the failure mode and effects analysis model to improve parathyroid hormone and adrenocorticotropic hormone testing

PubMed Central

Magnezi, Racheli; Hemi, Asaf; Hemi, Rina

2016-01-01

Background Risk management in health care systems applies to all hospital employees and directors as they deal with human life and emergency routines. There is a constant need to decrease risk and increase patient safety in the hospital environment. The purpose of this article is to review the laboratory testing procedures for parathyroid hormone and adrenocorticotropic hormone (which are characterized by short half-lives) and to track failure modes and risks, and offer solutions to prevent them. During a routine quality improvement review at the Endocrine Laboratory in Tel Hashomer Hospital, we discovered these tests are frequently repeated unnecessarily due to multiple failures. The repetition of the tests inconveniences patients and leads to extra work for the laboratory and logistics personnel as well as the nurses and doctors who have to perform many tasks with limited resources. Methods A team of eight staff members accompanied by the Head of the Endocrine Laboratory formed the team for analysis. The failure mode and effects analysis model (FMEA) was used to analyze the laboratory testing procedure and was designed to simplify the process steps and indicate and rank possible failures. Results A total of 23 failure modes were found within the process, 19 of which were ranked by level of severity. The FMEA model prioritizes failures by their risk priority number (RPN). For example, the most serious failure was the delay after the samples were collected from the department (RPN =226.1). Conclusion This model helped us to visualize the process in a simple way. After analyzing the information, solutions were proposed to prevent failures, and a method to completely avoid the top four problems was also developed. PMID:27980440

Earthquake and failure forecasting in real-time: A Forecasting Model Testing Centre

NASA Astrophysics Data System (ADS)

Filgueira, Rosa; Atkinson, Malcolm; Bell, Andrew; Main, Ian; Boon, Steven; Meredith, Philip

2013-04-01

Across Europe there are a large number of rock deformation laboratories, each of which runs many experiments. Similarly there are a large number of theoretical rock physicists who develop constitutive and computational models both for rock deformation and changes in geophysical properties. Here we consider how to open up opportunities for sharing experimental data in a way that is integrated with multiple hypothesis testing. We present a prototype for a new forecasting model testing centre based on e-infrastructures for capturing and sharing data and models to accelerate the Rock Physicist (RP) research. This proposal is triggered by our work on data assimilation in the NERC EFFORT (Earthquake and Failure Forecasting in Real Time) project, using data provided by the NERC CREEP 2 experimental project as a test case. EFFORT is a multi-disciplinary collaboration between Geoscientists, Rock Physicists and Computer Scientist. Brittle failure of the crust is likely to play a key role in controlling the timing of a range of geophysical hazards, such as volcanic eruptions, yet the predictability of brittle failure is unknown. Our aim is to provide a facility for developing and testing models to forecast brittle failure in experimental and natural data. Model testing is performed in real-time, verifiably prospective mode, in order to avoid selection biases that are possible in retrospective analyses. The project will ultimately quantify the predictability of brittle failure, and how this predictability scales from simple, controlled laboratory conditions to the complex, uncontrolled real world. Experimental data are collected from controlled laboratory experiments which includes data from the UCL Laboratory and from Creep2 project which will undertake experiments in a deep-sea laboratory. We illustrate the properties of the prototype testing centre by streaming and analysing realistically noisy synthetic data, as an aid to generating and improving testing methodologies in

Central hemodynamic responses during serial exercise tests in heart failure patients using implantable hemodynamic monitors.

PubMed

Ohlsson, A; Steinhaus, D; Kjellström, B; Ryden, L; Bennett, T

2003-06-01

Exercise testing is commonly used in patients with congestive heart failure for diagnostic and prognostic purposes. Such testing may be even more valuable if invasive hemodynamics are acquired. However, this will make the test more complex and expensive and only provides information from isolated moments. We studied serial exercise tests in heart failure patients with implanted hemodynamic monitors allowing recording of central hemodynamics. Twenty-one NYHA Class II-III heart failure patients underwent maximal exercise tests and submaximal bike or 6-min hall walk tests to quantify their hemodynamic responses and to study the feasibility of conducting exercise tests in patients with such devices. Patients were followed for 2-3 years with serial exercise tests. During maximal tests (n=70), heart rate increased by 52+/-19 bpm while S(v)O(2) decreased by 35+/-10% saturation units. RV systolic and diastolic pressure increased 29+/-11 and 11+/-6 mmHg, respectively, while pulmonary artery diastolic pressure increased 21+/-8 mmHg. Submaximal bike (n=196) and hall walk tests (n=172) resulted in S(v)O(2) changes of 80 and 91% of the maximal tests, while RV pressures ranged from 72 to 79% of maximal responses. An added potential value of implantable hemodynamic monitors in heart failure patients may be to quantitatively determine the true hemodynamic profile during standard non-invasive clinical exercise tests and to compare that to hemodynamic effects of regular exercise during daily living. It would be of interest to study whether such information could improve the ability to predict changes in a patient's clinical condition and to improve tailoring patient management.

Verification of the Multi-Axial, Temperature and Time Dependent (MATT) Failure Criterion

NASA Technical Reports Server (NTRS)

Richardson, David E.; Macon, David J.

2005-01-01

An extensive test and analytical effort has been completed by the Space Shuttle's Reusable Solid Rocket Motor (KSKM) nozzle program to characterize the failure behavior of two epoxy adhesives (TIGA 321 and EA946). As part of this effort, a general failure model, the "Multi-Axial, Temperature, and Time Dependent" or MATT failure criterion was developed. In the initial development of this failure criterion, tests were conducted to provide validation of the theory under a wide range of test conditions. The purpose of this paper is to present additional verification of the MATT failure criterion, under new loading conditions for the adhesives TIGA 321 and EA946. In many cases, the loading conditions involve an extrapolation from the conditions under which the material models were originally developed. Testing was conducted using three loading conditions: multi-axial tension, torsional shear, and non-uniform tension in a bondline condition. Tests were conducted at constant and cyclic loading rates ranging over four orders of magnitude. Tests were conducted under environmental conditions of primary interest to the RSRM program. The temperature range was not extreme, but the loading ranges were extreme (varying by four orders of magnitude). It should be noted that the testing was conducted at temperatures below the glass transition temperature of the TIGA 321 adhesive. However for the EA946, the testing was conducted at temperatures that bracketed the glass transition temperature.

Mini-interfacial fracture toughness as a new validated enamel-bonding effectiveness test.

PubMed

Pongprueksa, Pong; De Munck, Jan; Barreto, Bruno C; Karunratanakul, Kavin; Van Meerbeek, Bart

2016-09-01

Today׳s most commonly applied bonding effectiveness tests are criticized for their high variability and low reliability, the latter in particular with regard to measuring the actual strength of the adhesive interface. in continuation of previous research conducted at dentin, we hereby aimed to validate the novel mini-interfacial fracture toughness (mini-iFT) test on its applicability to assess bonding effectiveness of contemporary adhesives when bonded to enamel. The 3-step etch&rinse (E&R) adhesive OptiBond FL (Kerr), the 2-step self-etch (SE) adhesive Clearfil SE Bond (Kuraray Noritake) and the two multi-mode adhesives Clearfil S(3) Bond Plus (Kuraray Noritake) and Scotchbond Universal (3M ESPE), both used following a 2-step E&R and 1-step SE mode, were applied to clinically relevant, flattened enamel surfaces. A composite (Filtek Z100; 3M ESPE) build-up was made in layers. After 1-week water storage at 37°C, all specimens were sectioned perpendicular to the interface to obtain rectangular sticks. A mini-iFT notch was prepared at the adhesive-enamel interface using a thin diamond blade under water cooling. Finally, the specimens were loaded in a 4-point bending test until failure. the mini-iFT onto human enamel was significantly higher for the adhesives applied in E&R mode versus those applied in SE mode. The lowest mini-iFT was found for the adhesives applied following a 1-step SE approach. SEM fracture analysis revealed that all fractures originated at the adhesive-enamel interface and that the induced crack propagated preferentially along this interface. mini-iFT appeared a valid alternative method to assess the mechanical properties of adhesive-enamel interfaces. Copyright © 2016 Elsevier Ltd. All rights reserved.

10 CFR 26.139 - Reporting initial validity and drug test results.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Reporting initial validity and drug test results. 26.139 Section 26.139 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Licensee Testing Facilities § 26.139 Reporting initial validity and drug test results. (a) The licensee testing facility shall...

10 CFR 26.139 - Reporting initial validity and drug test results.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Reporting initial validity and drug test results. 26.139 Section 26.139 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Licensee Testing Facilities § 26.139 Reporting initial validity and drug test results. (a) The licensee testing facility shall...

10 CFR 26.139 - Reporting initial validity and drug test results.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false Reporting initial validity and drug test results. 26.139 Section 26.139 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Licensee Testing Facilities § 26.139 Reporting initial validity and drug test results. (a) The licensee testing facility shall...

Psychometrics of the PHQ-9 as a measure of depressive symptoms in patients with heart failure.

PubMed

Hammash, Muna H; Hall, Lynne A; Lennie, Terry A; Heo, Seongkum; Chung, Misook L; Lee, Kyoung Suk; Moser, Debra K

2013-10-01

Depression in patients with heart failure commonly goes undiagnosed and untreated. The Patient Health Questionnaire-9 (PHQ-9) is a simple, valid measure of depressive symptoms that may facilitate clinical assessment. It has not been validated in patients with heart failure. To test the reliability, and concurrent and construct validity of the PHQ-9 in patients with heart failure. A total of 322 heart failure patients (32% female, 61 ± 12 years, 56% New York Heart Association class III/IV) completed the PHQ-9, the Beck Depression Inventory-II (BDI-II), and the Control Attitudes Scale (CAS). Cronbach's alpha of .83 supported the internal consistency reliability of the PHQ-9 in this sample. Inter-item correlations (range .22-.66) and item-total correlation (except item 9) supported homogeneity of the PHQ-9. Spearman's rho of .80, (p < .001) between the PHQ-9 and the BDI-II supported the concurrent validity as did the agreement between the PHQ-9 and the BDI-II (Kappa = 0.64, p < .001). At cut-off score of 10, the PHQ-9 was 70% sensitive and 92% specific in identifying depressive symptoms, using the BDI-II scores as the criterion for comparison. Differences in PHQ-9 scores by level of perceived control measured by CAS (t(318) = -5.05, p < .001) supported construct validity. The PHQ-9 is a reliable, valid measure of depressive symptoms in patients with heart failure.

Membrane Accelerated Stress Test Development for Polymer Electrolyte Fuel Cell Durability Validated Using Field and Drive Cycle Testing

DOE PAGES

Mukundan, Rangachary; Baker, Andrew M.; Kusoglu, Ahmet; ...

2018-03-01

A combined chemical/mechanical accelerated stress test (AST) was developed for proton exchange membrane (PEM) fuel cells based on relative humidity cycling (RHC) between dry and saturated gases at open circuit voltage (OCV). Membrane degradation and failure were investigated using scanning electron microscopy and small- and wide-angle X-ray scattering. Changes to membrane thickness, hydrophilic domain spacing, and crystallinity were observed to be most similar between field-operated cells and OCV RHC ASTs, where local thinning and divot-type defects are the primary failure modes. While RHC in air also reproduces these failure modes, it is not aggressive enough to differentiate between different membranemore » types in >1,333 hours (55 days) of testing. Conversely, steady-state OCV tests result in significant ionomer morphology changes and global thinning, which do not replicate field degradation and failure modes. It is inferred that during the OCV RHC AST, the decay of the membrane's mechanical properties is accelerated such that materials can be evaluated in hundreds, instead of thousands, of hours, while replicating the degradation and failure modes of field operation; associated AST protocols are recommended as OCV RHC at 90°C for 500 hours with wet/dry cycle durations of 30s/45s and 2m/2m for automotive and bus operation, respectively.« less

Membrane Accelerated Stress Test Development for Polymer Electrolyte Fuel Cell Durability Validated Using Field and Drive Cycle Testing

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

Mukundan, Rangachary; Baker, Andrew M.; Kusoglu, Ahmet

A combined chemical/mechanical accelerated stress test (AST) was developed for proton exchange membrane (PEM) fuel cells based on relative humidity cycling (RHC) between dry and saturated gases at open circuit voltage (OCV). Membrane degradation and failure were investigated using scanning electron microscopy and small- and wide-angle X-ray scattering. Changes to membrane thickness, hydrophilic domain spacing, and crystallinity were observed to be most similar between field-operated cells and OCV RHC ASTs, where local thinning and divot-type defects are the primary failure modes. While RHC in air also reproduces these failure modes, it is not aggressive enough to differentiate between different membranemore » types in >1,333 hours (55 days) of testing. Conversely, steady-state OCV tests result in significant ionomer morphology changes and global thinning, which do not replicate field degradation and failure modes. It is inferred that during the OCV RHC AST, the decay of the membrane's mechanical properties is accelerated such that materials can be evaluated in hundreds, instead of thousands, of hours, while replicating the degradation and failure modes of field operation; associated AST protocols are recommended as OCV RHC at 90°C for 500 hours with wet/dry cycle durations of 30s/45s and 2m/2m for automotive and bus operation, respectively.« less

Validation test of 125 Ah advanced design IPV nickel-hydrogen flight cells

NASA Technical Reports Server (NTRS)

Smithrick, John J.; Hall, Stephen W.

1993-01-01

An update of validation test results confirming the advanced design nickel-hydrogen cell is presented. An advanced 125 Ah individual pressure vessel Ni-H cell was designed. The primary function of the advanced cell is to store and deliver energy for long-term LEO spacecraft missions. The new features of this design are: (1) use of 26 percent rather than 31 percent KOH electrolyte; (2) use of a patented catalyzed wall wick; (3) use of serrated-edge separators to facilitate gaseous O and H flow within the cell, while maintaining physical contact with the wall wick for electrolyte management; and (4) use of a floating rather than a fixed stack to accommodate Ni electrode expansion due to charge/discharge cycling. The significant improvements resulting from these innovations are extended cycle life; enhanced thermal, electrolyte, and oxygen management; and accommodation of Ni electrode expansion. Six 125 Ah flight cells based on this design were fabricated; the catalyzed wall wick cells have been cycled for over 19,000 cycles with no cell failures in the continuing test. Two of the noncatalyzed wall wick cells failed (cycles 9588 and 13,900).

Eye-Tracking as a Tool in Process-Oriented Reading Test Validation

ERIC Educational Resources Information Center

Solheim, Oddny Judith; Uppstad, Per Henning

2011-01-01

The present paper addresses the continuous need for methodological reflection on how to validate inferences made on the basis of test scores. Validation is a process that requires many lines of evidence. In this article we discuss the potential of eye tracking methodology in process-oriented reading test validation. Methodological considerations…

The validation of Huffaz Intelligence Test (HIT)

NASA Astrophysics Data System (ADS)

Rahim, Mohd Azrin Mohammad; Ahmad, Tahir; Awang, Siti Rahmah; Safar, Ajmain

2017-08-01

In general, a hafiz who can memorize the Quran has many specialties especially in respect to their academic performances. In this study, the theory of multiple intelligences introduced by Howard Gardner is embedded in a developed psychometric instrument, namely Huffaz Intelligence Test (HIT). This paper presents the validation and the reliability of HIT of some tahfiz students in Malaysia Islamic schools. A pilot study was conducted involving 87 huffaz who were randomly selected to answer the items in HIT. The analysis method used includes Partial Least Square (PLS) on reliability, convergence and discriminant validation. The study has validated nine intelligences. The findings also indicated that the composite reliabilities for the nine types of intelligences are greater than 0.8. Thus, the HIT is a valid and reliable instrument to measure the multiple intelligences among huffaz.

Veggie and the VEG-01 Hardware Validation Test

NASA Technical Reports Server (NTRS)

Massa, Gioia; wheeler, Ray; Smith, Trent

2015-01-01

This presentation presents a brief overview of KSC plant science hardware for space and then details the Veggie hardware and the VEG-01 hardware validation test. The test results and future plans are discussed.

TESTING BALANCE AND FALL RISK IN PERSONS WITH PARKINSON DISEASE, AN ARGUMENT FOR ECOLOGICALLY VALID TESTING

PubMed Central

Foreman, K. Bo; Addison, Odessa; Kim, Han S.; Dibble, Leland E.

2010-01-01

Introduction Despite clear deficits in postural control, most clinical examination tools lack accuracy in identifying persons with Parkinson disease (PD) who have fallen or are at risk for falls. We assert that this is in part due to the lack of ecological validity of the testing. Methods To test this assertion, we examined the responsiveness and predictive validity of the Functional Gait Assessment (FGA), the Pull test, and the Timed up and Go (TUG) during clinically defined ON and OFF medication states. To address responsiveness, ON/OFF medication performance was compared. To address predictive validity, areas under the curve (AUC) of receiver operating characteristic (ROC) curves were compared. Comparisons were made using separate non-parametric tests. Results Thirty-six persons (24 male, 12 female) with PD (22 fallers, 14 non-fallers) participated. Only the FGA was able to detect differences between fallers and non-fallers for both ON/OFF medication testing. The predictive validity of the FGA and the TUG for fall identification was higher during OFF medication compared to ON medication testing. The predictive validity of the FGA was higher than the TUG and the Pull test during ON and OFF medication testing. Discussion In order to most accurately identify fallers, clinicians should test persons with PD in ecologically relevant conditions and tasks. In this study, interpretation of the OFF medication performance and use of the FGA provided more accurate prediction of those who would fall. PMID:21215674

Factors associated with failure to return for HIV test results in a free and anonymous screening centre.

PubMed

Laanani, Moussa; Dozol, Adrien; Meyer, Laurence; David, Stéphane; Camara, Sékou; Segouin, Christophe; Troude, Pénélope

2015-07-01

Free and anonymous screening centres (CDAG: Centres de Depistage Anononyme et Gratuit) are public facilities set up for HIV infection diagnosis in France. Some people visiting CDAG fail to return for test results and are not informed of their serology. This study aimed to assess factors associated with failure to return for HIV test results. Patients visiting the Fernand-Widal CDAG (Paris) for an HIV test in January-February 2011 were eligible to take part in the study. Data were collected with an anonymous self-administered questionnaire. Factors associated with failure to return were assessed using logistic regression models. Of the 710 participants (participation rate 88%), 46 patients failed to return. Not specifying birthplace and not living in the region of Paris were associated with failure to return. Those who perceived no risk of HIV infection and those who felt they were more at risk than other people were both statistically associated with failure to return. Self-perceived risk seemed to be of chief concern for failure to return for HIV test results and should be considered during pre-test counselling. © The Author(s) 2014.

Natriuretic peptide-guided management in heart failure.

PubMed

Chioncel, Ovidiu; Collins, Sean P; Greene, Stephen J; Ambrosy, Andrew P; Vaduganathan, Muthiah; Macarie, Cezar; Butler, Javed; Gheorghiade, Mihai

2016-08-01

Heart failure is a clinical syndrome that manifests from various cardiac and noncardiac abnormalities. Accordingly, rapid and readily accessible methods for diagnosis and risk stratification are invaluable for providing clinical care, deciding allocation of scare resources, and designing selection criteria for clinical trials. Natriuretic peptides represent one of the most important diagnostic and prognostic tools available for the care of heart failure patients. Natriuretic peptide testing has the distinct advantage of objectivity, reproducibility, and widespread availability.The concept of tailoring heart failure management to achieve a target value of natriuretic peptides has been tested in various clinical trials and may be considered as an effective method for longitudinal biomonitoring and guiding escalation of heart failure therapies with overall favorable results.Although heart failure trials support efficacy and safety of natriuretic peptide-guided therapy as compared with usual care, the relationship between natriuretic peptide trajectory and clinical benefit has not been uniform across the trials, and certain subgroups have not shown robust benefit. Furthermore, the precise natriuretic peptide value ranges and time intervals of testing are still under investigation. If natriuretic peptides fail to decrease following intensification of therapy, further work is needed to clarify the optimal pharmacologic approach. Despite decreasing natriuretic peptide levels, some patients may present with other high-risk features (e.g. elevated troponin). A multimarker panel investigating multiple pathological processes will likely be an optimal alternative, but this will require prospective validation.Future research will be needed to clarify the type and magnitude of the target natriuretic peptide therapeutic response, as well as the duration of natriuretic peptide-guided therapy in heart failure patients.

Face Validity of Test and Acceptance of Generalized Personality Interpretations

ERIC Educational Resources Information Center

Delprato, Dennis J.

1975-01-01

The degree to which variations in the face validity of psychological tests affected students' willingness to accept personality interpretations was studied. Acceptance of personality interpretations was compared for four types of tests which varied in face validity. The relationship between judged accuracy and rated likability of the…

Self-care confidence may be more important than cognition to influence self-care behaviors in adults with heart failure: Testing a mediation model.

PubMed

Vellone, Ercole; Pancani, Luca; Greco, Andrea; Steca, Patrizia; Riegel, Barbara

2016-08-01

Cognitive impairment can reduce the self-care abilities of heart failure patients. Theory and preliminary evidence suggest that self-care confidence may mediate the relationship between cognition and self-care, but further study is needed to validate this finding. The aim of this study was to test the mediating role of self-care confidence between specific cognitive domains and heart failure self-care. Secondary analysis of data from a descriptive study. Three out-patient sites in Pennsylvania and Delaware, USA. A sample of 280 adults with chronic heart failure, 62 years old on average and mostly male (64.3%). Data on heart failure self-care and self-care confidence were collected with the Self-Care of Heart Failure Index 6.2. Data on cognition were collected by trained research assistants using a neuropsychological test battery measuring simple and complex attention, processing speed, working memory, and short-term memory. Sociodemographic data were collected by self-report. Clinical information was abstracted from the medical record. Mediation analysis was performed with structural equation modeling and indirect effects were evaluated with bootstrapping. Most participants had at least 1 impaired cognitive domain. In mediation models, self-care confidence consistently influenced self-care and totally mediated the relationship between simple attention and self-care and between working memory and self-care (comparative fit index range: .929-.968; root mean squared error of approximation range: .032-.052). Except for short-term memory, which had a direct effect on self-care maintenance, the other cognitive domains were unrelated to self-care. Self-care confidence appears to be an important factor influencing heart failure self-care even in patients with impaired cognition. As few studies have successfully improved cognition, interventions addressing confidence should be considered as a way to improve self-care in this population. Copyright © 2016 Elsevier Ltd. All

Does Test Preparation Work? Implications for Score Validity

ERIC Educational Resources Information Center

Xie, Qin

2013-01-01

This article reports an empirical study that examined the pattern of test preparation for College English Test Band 4 (CET4) and the differential effects of test preparation practices on its scores, thereby drawing implications for CET4 score validity. Data collection involved 1,003 test takers of CET4. A pretest was administered at the beginning…

Validation of Physics Standardized Test Items

NASA Astrophysics Data System (ADS)

Marshall, Jill

2008-10-01

The Texas Physics Assessment Team (TPAT) examined the Texas Assessment of Knowledge and Skills (TAKS) to determine whether it is a valid indicator of physics preparation for future course work and employment, and of the knowledge and skills needed to act as an informed citizen in a technological society. We categorized science items from the 2003 and 2004 10th and 11th grade TAKS by content area(s) covered, knowledge and skills required to select the correct answer, and overall quality. We also analyzed a 5000 student sample of item-level results from the 2004 11th grade exam using standard statistical methods employed by test developers (factor analysis and Item Response Theory). Triangulation of our results revealed strengths and weaknesses of the different methods of analysis. The TAKS was found to be only weakly indicative of physics preparation and we make recommendations for increasing the validity of standardized physics testing..

Validation of antibiotic residue tests for dairy goats.

PubMed

Zeng, S S; Hart, S; Escobar, E N; Tesfai, K

1998-03-01

The SNAP test, LacTek test (B-L and CEF), Charm Bacillus sterothermophilus var. calidolactis disk assay (BsDA), and Charm II Tablet Beta-lactam sequential test were validated using antibiotic-fortified and -incurred goat milk following the protocol for test kit validations of the U.S. Food and Drug Administration Center for Veterinary Medicine. SNAP, Charm BsDA, and Charm II Tablet Sequential tests were sensitive and reliable in detecting antibiotic residues in goat milk. All three assays showed greater than 90% sensitivity and specificity at tolerance and detection levels. However, caution should be taken in interpreting test results at detection levels. Because of the high sensitivity of these three tests, false-violative results could be obtained in goat milk containing antibiotic residues below the tolerance level. Goat milk testing positive by these tests must be confirmed using a more sophisticated methodology, such as high-performance liquid chromatography, before the milk is condemned. LacTek B-L test did not detect several antibiotics, including penicillin G, in goat milk at tolerance levels. However, LacTek CEF was excellent in detecting ceftiofur residue in goat milk.

The Validity of IQ Scores Derived from Readiness Screening Tests

ERIC Educational Resources Information Center

Telegdy, Gabriel A.

1976-01-01

The Screening Test of Academic Readiness (STAR) and the Peabody Picture Vocabulary Test (PPVT) were administered to 52 kindergarten children to reveal the convergent validity of IQ scores derived from the STAR. The findings raise doubts about the validity of the deviation IQs derived from the STAR. (Author)

The Math Essential Skills Screener--Upper Elementary Version (MESS-U): Studies of Reliability and Validity

ERIC Educational Resources Information Center

Erford, Bradley T.; Biddison, Amanda R.

2006-01-01

The Math Essential Skills Screener--Upper Elementary Version (MESS-U) is part of a series of screening tests designed to help identify students ages 9-11 who are at risk for mathematics failure. Internal consistency, test-retest reliability, item analysis, decision efficiency, convergent validity and factorial validity of the MESS-U were studied…

Retrieval Cues on Tests: A Strategy for Helping Students Overcome Retrieval Failure

ERIC Educational Resources Information Center

Gallagher, Kristel M.

2017-01-01

Students often struggle to recall information on tests, frequently claiming to experience a "retrieval failure" of learned information. Thus, the retrieval of information from memory may be a roadblock to student success. I propose a relatively simple adjustment to the wording of test items to help eliminate this potential barrier.…

Structural testing for static failure, flutter and other scary things

NASA Technical Reports Server (NTRS)

Ricketts, R. H.

1983-01-01

Ground test and flight test methods are described that may be used to highlight potential structural problems that occur on aircraft. Primary interest is focused on light-weight general aviation airplanes. The structural problems described include static strength failure, aileron reversal, static divergence, and flutter. An example of each of the problems is discussed to illustrate how the data acquired during the tests may be used to predict the occurrence of the structural problem. While some rules of thumb for the prediction of structural problems are given the report is not intended to be used explicitly as a structural analysis handbook.

Neurodevelopmental and Cognitive Outcomes in Children With Intestinal Failure.

PubMed

Chesley, Patrick M; Sanchez, Sabrina E; Melzer, Lilah; Oron, Assaf P; Horslen, Simon P; Bennett, F Curt; Javid, Patrick J

2016-07-01

Recent advances in medical and surgical management have led to improved long-term survival in children with intestinal failure. Yet, limited data exist on their neurodevelopmental and cognitive outcomes. The aim of the present study was to measure neurodevelopmental outcomes in children with intestinal failure. Children enrolled in a regional intestinal failure program underwent prospective neurodevelopmental and psychometric evaluation using a validated scoring tool. Cognitive impairment was defined as a mental developmental index <70. Neurodevelopmental impairment was defined as cerebral palsy, visual or hearing impairment, or cognitive impairment. Univariate analyses were performed using the Wilcoxon rank-sum test. Data are presented as median (range). Fifteen children with a remnant bowel length of 18 (5-85) cm were studied at age 17 (12-67) months. Thirteen patients remained dependent on parenteral nutrition. Twelve (80%) subjects scored within the normal range on cognitive testing. Each child with cognitive impairment was noted to have additional risk factors independent of intestinal failure including cardiac arrest and extreme prematurity. On univariate analysis, cognitive impairment was associated with longer inpatient hospital stays, increased number of surgical procedures, and prematurity (P < 0.02). In total, 4 (27%) children demonstrated findings consistent with neurodevelopmental impairment. A majority of children with intestinal failure demonstrated normal neurodevelopmental and cognitive outcomes on psychometric testing. These data suggest that children with intestinal failure without significant comorbidity may be at low risk for long-term neurodevelopmental impairment.

An exploratory study into the effect of time-restricted internet access on face-validity, construct validity and reliability of postgraduate knowledge progress testing

PubMed Central

2013-01-01

Background Yearly formative knowledge testing (also known as progress testing) was shown to have a limited construct-validity and reliability in postgraduate medical education. One way to improve construct-validity and reliability is to improve the authenticity of a test. As easily accessible internet has become inseparably linked to daily clinical practice, we hypothesized that allowing internet access for a limited amount of time during the progress test would improve the perception of authenticity (face-validity) of the test, which would in turn improve the construct-validity and reliability of postgraduate progress testing. Methods Postgraduate trainees taking the yearly knowledge progress test were asked to participate in a study where they could access the internet for 30 minutes at the end of a traditional pen and paper test. Before and after the test they were asked to complete a short questionnaire regarding the face-validity of the test. Results Mean test scores increased significantly for all training years. Trainees indicated that the face-validity of the test improved with internet access and that they would like to continue to have internet access during future testing. Internet access did not improve the construct-validity or reliability of the test. Conclusion Improving the face-validity of postgraduate progress testing, by adding the possibility to search the internet for a limited amount of time, positively influences test performance and face-validity. However, it did not change the reliability or the construct-validity of the test. PMID:24195696

Validation of Helicopter Gear Condition Indicators Using Seeded Fault Tests

NASA Technical Reports Server (NTRS)

Dempsey, Paula; Brandon, E. Bruce

2013-01-01

A "seeded fault test" in support of a rotorcraft condition based maintenance program (CBM), is an experiment in which a component is tested with a known fault while health monitoring data is collected. These tests are performed at operating conditions comparable to operating conditions the component would be exposed to while installed on the aircraft. Performance of seeded fault tests is one method used to provide evidence that a Health Usage Monitoring System (HUMS) can replace current maintenance practices required for aircraft airworthiness. Actual in-service experience of the HUMS detecting a component fault is another validation method. This paper will discuss a hybrid validation approach that combines in service-data with seeded fault tests. For this approach, existing in-service HUMS flight data from a naturally occurring component fault will be used to define a component seeded fault test. An example, using spiral bevel gears as the targeted component, will be presented. Since the U.S. Army has begun to develop standards for using seeded fault tests for HUMS validation, the hybrid approach will be mapped to the steps defined within their Aeronautical Design Standard Handbook for CBM. This paper will step through their defined processes, and identify additional steps that may be required when using component test rig fault tests to demonstrate helicopter CI performance. The discussion within this paper will provide the reader with a better appreciation for the challenges faced when defining a seeded fault test for HUMS validation.

A Historical Overview on the Concept of Validity in Language Testing

ERIC Educational Resources Information Center

Hamavandy, Mehraban; Kiany, Gholam Reza

2014-01-01

This article provides an overview on language test validation theories, especially the Messickian view on construct validity and the way it's been translated into practice. First, a brief historical synopsis will be set forth, followed by recent views on test validity as advanced by Messick and Kane. The review goes on to lay out the similarities…

Shifting the Focus of Validity for Test Use

ERIC Educational Resources Information Center

Moss, Pamela A.

2016-01-01

The conventional focus of validity in educational measurement has been on intended interpretations and uses of test scores. Empirical studies of test use by teachers, administrators and policy-makers show that actual interpretations and uses of test scores in context are invariably shaped by local users' questions, which frequently require…

The validity of three tests of temperament in guppies (Poecilia reticulata).

PubMed

Burns, James G

2008-11-01

Differences in temperament (consistent differences among individuals in behavior) can have important effects on fitness-related activities such as dispersal and competition. However, evolutionary ecologists have put limited effort into validating their tests of temperament. This article attempts to validate three standard tests of temperament in guppies: the open-field test, emergence test, and novel-object test. Through multiple reliability trials, and comparison of results between different types of test, this study establishes the confidence that can be placed in these temperament tests. The open-field test is shown to be a good test of boldness and exploratory behavior; the open-field test was reliable when tested in multiple ways. There were problems with the emergence test and novel-object test, which leads one to conclude that the protocols used in this study should not be considered valid tests for this species. (PsycINFO Database Record (c) 2008 APA, all rights reserved).

Determination of Failure Point of Asphalt-Mixture Fatigue-Test Results Using the Flow Number Method

NASA Astrophysics Data System (ADS)

Wulan, C. E. P.; Setyawan, A.; Pramesti, F. P.

2018-03-01

The failure point of the results of fatigue tests of asphalt mixtures performed in controlled stress mode is difficult to determine. However, several methods from empirical studies are available to solve this problem. The objectives of this study are to determine the fatigue failure point of the results of indirect tensile fatigue tests using the Flow Number Method and to determine the best Flow Number model for the asphalt mixtures tested. In order to achieve these goals, firstly the best asphalt mixture of three was selected based on their Marshall properties. Next, the Indirect Tensile Fatigue Test was performed on the chosen asphalt mixture. The stress-controlled fatigue tests were conducted at a temperature of 20°C and frequency of 10 Hz, with the application of three loads: 500, 600, and 700 kPa. The last step was the application of the Flow Number methods, namely the Three-Stages Model, FNest Model, Francken Model, and Stepwise Method, to the results of the fatigue tests to determine the failure point of the specimen. The chosen asphalt mixture is EVA (Ethyl Vinyl Acetate) polymer -modified asphalt mixture with 6.5% OBC (Optimum Bitumen Content). Furthermore, the result of this study shows that the failure points of the EVA-modified asphalt mixture under loads of 500, 600, and 700 kPa are 6621, 4841, and 611 for the Three-Stages Model; 4271, 3266, and 537 for the FNest Model; 3401, 2431, and 421 for the Francken Model, and 6901, 6841, and 1291 for the Stepwise Method, respectively. These different results show that the bigger the loading, the smaller the number of cycles to failure. However, the best FN results are shown by the Three-Stages Model and the Stepwise Method, which exhibit extreme increases after the constant development of accumulated strain.

The Air Force Officer Qualifying Test: Validity, Fairness, and Bias

DTIC Science & Technology

2010-01-01

scores. The Standards for Educational and Psychological Testing (AERA, APA, and NCME, 1999) provides a set of guidelines published and endorsed by the...determining the validity and bias of selection tests falls upon professionals in the discipline of industrial/organizational psychology 20 See Roper v. Dep’t...i). 30 The Air Force Officer Qualifying Test : Validity, Fairness, and Bias and closely related fields (e.g., educational psychology and

Assessing validity by comparing transition and static measures of dyspnea in patients with acute decompensated heart failure.

PubMed

Smithline, Howard A; Caglar, Selin; Blank, Fidela S J

2010-01-01

This study assessed the convergent validity of 2 dyspnea measures, the transition measure and the change measure, by comparing them with each other in patients admitted to the hospital with acute decompensated heart failure. Static measures of dyspnea were obtained at baseline (pre-static measure) and at time 1 hour and 4 hour (post-static measures). The change measure was calculated as the difference between the pre-static and post-static measures. Transition measures were obtained at time 1 hour and 4 hour. Visual analog scales and Likert scales were used. Both physicians and patients measured the dyspnea independently. A total of 112 patients had complete data sets at time 0 and 1 hour and 86 patients had complete data sets at all 3 time points. Correlations were calculated between the transition measures and static measures (pre-static, post-static, and change measure). Bland-Altman plots were generated and the mean difference and limits of agreement between the transition measures and the change measures were calculated. In general, short-term dyspnea assessment using transition measures and serial static measures can not be used to validate each other in this population of patients being admitted with acute decompensated heart failure. © 2010 Wiley Periodicals, Inc.

Simulations of carbon fiber composite delamination tests

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

Kay, G

2007-10-25

Simulations of mode I interlaminar fracture toughness tests of a carbon-reinforced composite material (BMS 8-212) were conducted with LSDYNA. The fracture toughness tests were performed by U.C. Berkeley. The simulations were performed to investigate the validity and practicality of employing decohesive elements to represent interlaminar bond failures that are prevalent in carbon-fiber composite structure penetration events. The simulations employed a decohesive element formulation that was verified on a simple two element model before being employed to perform the full model simulations. Care was required during the simulations to ensure that the explicit time integration of LSDYNA duplicate the near steady-statemore » testing conditions. In general, this study validated the use of employing decohesive elements to represent the interlaminar bond failures seen in carbon-fiber composite structures, but the practicality of employing the elements to represent the bond failures seen in carbon-fiber composite structures during penetration events was not established.« less

How to test validity in orthodontic research: a mixed dentition analysis example.

PubMed

Donatelli, Richard E; Lee, Shin-Jae

2015-02-01

The data used to test the validity of a prediction method should be different from the data used to generate the prediction model. In this study, we explored whether an independent data set is mandatory for testing the validity of a new prediction method and how validity can be tested without independent new data. Several validation methods were compared in an example using the data from a mixed dentition analysis with a regression model. The validation errors of real mixed dentition analysis data and simulation data were analyzed for increasingly large data sets. The validation results of both the real and the simulation studies demonstrated that the leave-1-out cross-validation method had the smallest errors. The largest errors occurred in the traditional simple validation method. The differences between the validation methods diminished as the sample size increased. The leave-1-out cross-validation method seems to be an optimal validation method for improving the prediction accuracy in a data set with limited sample sizes. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

ASTM Validates Air Pollution Test Methods

ERIC Educational Resources Information Center

Chemical and Engineering News, 1973

1973-01-01

The American Society for Testing and Materials (ASTM) has validated six basic methods for measuring pollutants in ambient air as the first part of its Project Threshold. Aim of the project is to establish nationwide consistency in measuring pollutants; determining precision, accuracy and reproducibility of 35 standard measuring methods. (BL)

An Integrated Approach to Establish Validity and Reliability of Reading Tests

ERIC Educational Resources Information Center

Razi, Salim

2012-01-01

This study presents the processes of developing and establishing reliability and validity of a reading test by administering an integrative approach as conventional reliability and validity measures superficially reveals the difficulty of a reading test. In this respect, analysing vocabulary frequency of the test is regarded as a more eligible way…

Evaluating the Medical Symptom Validity Test (MSVT) in a Sample of Veterans Between the Ages of 18 to 64.

PubMed

Reslan, Summar; Axelrod, Bradley N

2017-01-01

The purpose of the current study was to compare three potential profiles of the Medical Symptom Validity Test (MSVT; Pass, Genuine Memory Impairment Profile [GMIP], and Fail) on other freestanding and embedded performance validity tests (PVTs). Notably, a quantitatively computed version of the GMIP was utilized in this investigation. Data obtained from veterans referred for a neuropsychological evaluation in a metropolitan Veteran Affairs medical center were included (N = 494). Individuals age 65 and older were not included to exclude individuals with dementia from this investigation. The sample revealed 222 (45%) in the Pass group. Of the 272 who failed the easy subtests of the MSVT, 221 (81%) met quantitative criteria for the GMIP and 51 (19%) were classified as Fail. The Pass group failed fewer freestanding and embedded PVTs and obtained higher raw scores on all PVTs than both GMIP and Fail groups. The differences in performances of the GMIP and Fail groups were minimal. Specifically, GMIP protocols failed fewer freestanding PVTs than the Fail group; failure on embedded PVTs did not differ between GMIP and Fail. The MSVT GMIP incorporates the presence of clinical correlates of disability to assist with this distinction, but future research should consider performances on other freestanding measures of performance validity to differentiate cognitive impairment from invalidity.

The CPT Reading Comprehension Test: A Validity Study.

ERIC Educational Resources Information Center

Napoli, Anthony R.; Raymond, Lanette A.; Coffey, Cheryl A.; Bosco, Diane M.

1998-01-01

Describes a study done at Suffolk County Community College (New York) that assessed the validity of the College Board's Computerized Placement Test in Reading Comprehension (CPT-R) by comparing test results of 1,154 freshmen with the results of the Degree of Power Reading Test. Results confirmed the CPT-R's reliability in identifying basic…

Validity and Reliability of a Medicine Ball Explosive Power Test.

ERIC Educational Resources Information Center

Stockbrugger, Barry A.; Haennel, Robert G.

2001-01-01

Evaluated the validity and reliability of a medicine ball throw test to evaluate explosive power. Data on competitive sand volleyball players who performed a medicine ball throw and a standard countermovement jump indicated that the medicine ball throw test was a valid and reliable way to assess explosive power for an analogous total-body movement…

Failure Behavior Characterization of Mo-Modified Ti Surface by Impact Test and Finite Element Analysis

NASA Astrophysics Data System (ADS)

Ma, Yong; Qin, Jianfeng; Zhang, Xiangyu; Lin, Naiming; Huang, Xiaobo; Tang, Bin

2015-07-01

Using the impact test and finite element simulation, the failure behavior of the Mo-modified layer on pure Ti was investigated. In the impact test, four loads of 100, 300, 500, and 700 N and 104 impacts were adopted. The three-dimensional residual impact dents were examined using an optical microscope (Olympus-DSX500i), indicating that the impact resistance of the Ti surface was improved. Two failure modes cohesive and wearing were elucidated by electron backscatter diffraction and energy-dispersive spectrometer performed in a field-emission scanning electron microscope. Through finite element forward analysis performed at a typical impact load of 300 N, stress-strain distributions in the Mo-modified Ti were quantitatively determined. In addition, the failure behavior of the Mo-modified layer was determined and an ideal failure model was proposed for high-load impact, based on the experimental and finite element forward analysis results.

Progressive Damage and Failure Analysis of Composite Laminates

NASA Astrophysics Data System (ADS)

Joseph, Ashith P. K.

Composite materials are widely used in various industries for making structural parts due to higher strength to weight ratio, better fatigue life, corrosion resistance and material property tailorability. To fully exploit the capability of composites, it is required to know the load carrying capacity of the parts made of them. Unlike metals, composites are orthotropic in nature and fails in a complex manner under various loading conditions which makes it a hard problem to analyze. Lack of reliable and efficient failure analysis tools for composites have led industries to rely more on coupon and component level testing to estimate the design space. Due to the complex failure mechanisms, composite materials require a very large number of coupon level tests to fully characterize the behavior. This makes the entire testing process very time consuming and costly. The alternative is to use virtual testing tools which can predict the complex failure mechanisms accurately. This reduces the cost only to it's associated computational expenses making significant savings. Some of the most desired features in a virtual testing tool are - (1) Accurate representation of failure mechanism: Failure progression predicted by the virtual tool must be same as those observed in experiments. A tool has to be assessed based on the mechanisms it can capture. (2) Computational efficiency: The greatest advantages of a virtual tools are the savings in time and money and hence computational efficiency is one of the most needed features. (3) Applicability to a wide range of problems: Structural parts are subjected to a variety of loading conditions including static, dynamic and fatigue conditions. A good virtual testing tool should be able to make good predictions for all these different loading conditions. The aim of this PhD thesis is to develop a computational tool which can model the progressive failure of composite laminates under different quasi-static loading conditions. The analysis

Solar Sail Models and Test Measurements Correspondence for Validation Requirements Definition

NASA Technical Reports Server (NTRS)

Ewing, Anthony; Adams, Charles

2004-01-01

Solar sails are being developed as a mission-enabling technology in support of future NASA science missions. Current efforts have advanced solar sail technology sufficient to justify a flight validation program. A primary objective of this activity is to test and validate solar sail models that are currently under development so that they may be used with confidence in future science mission development (e.g., scalable to larger sails). Both system and model validation requirements must be defined early in the program to guide design cycles and to ensure that relevant and sufficient test data will be obtained to conduct model validation to the level required. A process of model identification, model input/output documentation, model sensitivity analyses, and test measurement correspondence is required so that decisions can be made to satisfy validation requirements within program constraints.

Construction and Evaluation of Reliability and Validity of Reasoning Ability Test

ERIC Educational Resources Information Center

Bhat, Mehraj A.

2014-01-01

This paper is based on the construction and evaluation of reliability and validity of reasoning ability test at secondary school students. In this paper an attempt was made to evaluate validity, reliability and to determine the appropriate standards to interpret the results of reasoning ability test. The test includes 45 items to measure six types…

Test Anxiety and the Validity of Cognitive Tests: A Confirmatory Factor Analysis Perspective and Some Empirical Findings

ERIC Educational Resources Information Center

Wicherts, Jelte M.; Scholten, Annemarie Zand

2010-01-01

The validity of cognitive ability tests is often interpreted solely as a function of the cognitive abilities that these tests are supposed to measure, but other factors may be at play. The effects of test anxiety on the criterion related validity (CRV) of tests was the topic of a recent study by Reeve, Heggestad, and Lievens (2009) (Reeve, C. L.,…

40 CFR 610.24 - Validity of test data.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 30 2011-07-01 2011-07-01 false Validity of test data. 610.24 Section 610.24 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY RETROFIT DEVICES Test Procedures and Evaluation Criteria Evaluation Criteria for the Preliminary...

40 CFR 610.24 - Validity of test data.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 31 2012-07-01 2012-07-01 false Validity of test data. 610.24 Section 610.24 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY RETROFIT DEVICES Test Procedures and Evaluation Criteria Evaluation Criteria for the Preliminary...

40 CFR 610.24 - Validity of test data.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 30 2014-07-01 2014-07-01 false Validity of test data. 610.24 Section 610.24 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY RETROFIT DEVICES Test Procedures and Evaluation Criteria Evaluation Criteria for the Preliminary...

40 CFR 610.24 - Validity of test data.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 31 2013-07-01 2013-07-01 false Validity of test data. 610.24 Section 610.24 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY RETROFIT DEVICES Test Procedures and Evaluation Criteria Evaluation Criteria for the Preliminary...

40 CFR 610.24 - Validity of test data.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Validity of test data. 610.24 Section 610.24 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY RETROFIT DEVICES Test Procedures and Evaluation Criteria Evaluation Criteria for the Preliminary...

Test validity and performance validity: considerations in providing a framework for development of an ability-focused neuropsychological test battery.

PubMed

Larrabee, Glenn J

2014-11-01

Literature on test validity and performance validity is reviewed to propose a framework for specification of an ability-focused battery (AFB). Factor analysis supports six domains of ability: first, verbal symbolic; secondly, visuoperceptual and visuospatial judgment and problem solving; thirdly, sensorimotor skills; fourthly, attention/working memory; fifthly, processing speed; finally, learning and memory (which can be divided into verbal and visual subdomains). The AFB should include at least three measures for each of the six domains, selected based on various criteria for validity including sensitivity to presence of disorder, sensitivity to severity of disorder, correlation with important activities of daily living, and containing embedded/derived measures of performance validity. Criterion groups should include moderate and severe traumatic brain injury, and Alzheimer's disease. Validation groups should also include patients with left and right hemisphere stroke, to determine measures sensitive to lateralized cognitive impairment and so that the moderating effects of auditory comprehension impairment and neglect can be analyzed on AFB measures. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Development and Validation of an Abbreviated Questionnaire to Easily Measure Cognitive Failure in ICU Survivors: A Multicenter Study.

PubMed

Wassenaar, Annelies; de Reus, Jorn; Donders, A Rogier T; Schoonhoven, Lisette; Cremer, Olaf L; de Lange, Dylan W; van Dijk, Diederik; Slooter, Arjen J C; Pickkers, Peter; van den Boogaard, Mark

2018-01-01

To develop and validate an abbreviated version of the Cognitive Failure Questionnaire that can be used by patients as part of self-assessment to measure functional cognitive outcome in ICU survivors. A retrospective multicenter observational study. The ICUs of two Dutch university hospitals. Adult ICU survivors. None. Cognitive functioning was evaluated between 12 and 24 months after ICU discharge using the full 25-item Cognitive Failure Questionnaire (CFQ-25). Incomplete CFQ-25 questionnaires were excluded from analysis. Forward selection in a linear regression model was used in hospital A to assess which of the CFQ-25 items should be included to prevent a significant loss of correlation between an abbreviated and the full CFQ-25. Subsequently, the performance of an abbreviated Cognitive Failure Questionnaire was determined in hospital B using Pearson's correlation. A Bland-Altman plot was used to examine whether the reduced-item outcome scores of an abbreviated Cognitive Failure Questionnaire were a replacement for the full CFQ-25 outcome scores. Among 1,934 ICU survivors, 1,737 were included, 819 in hospital A, 918 in hospital B. The Pearson's correlation between the abbreviated 14-item Cognitive Failure Questionnaire (CFQ-14) and the CFQ-25 was 0.99. The mean of the difference scores was -0.26, and 95% of the difference scores fell within +5 and -5.5 on a 100-point maximum score. It is feasible to use the abbreviated CFQ-14 to measure self-reported cognitive failure in ICU survivors as this questionnaire has a similar performance as the full CFQ-25.

Integrated Resilient Aircraft Control Project Full Scale Flight Validation

NASA Technical Reports Server (NTRS)

Bosworth, John T.

2009-01-01

Objective: Provide validation of adaptive control law concepts through full scale flight evaluation. Technical Approach: a) Engage failure mode - destabilizing or frozen surface. b) Perform formation flight and air-to-air tracking tasks. Evaluate adaptive algorithm: a) Stability metrics. b) Model following metrics. Full scale flight testing provides an ability to validate different adaptive flight control approaches. Full scale flight testing adds credence to NASA's research efforts. A sustained research effort is required to remove the road blocks and provide adaptive control as a viable design solution for increased aircraft resilience.

Application of fiber grating-based acoustic sensor in progressive failure testing of e-glass/vinylester curve composites

NASA Astrophysics Data System (ADS)

Azmi, Asrul Izam; Raju, Raju; Peng, Gang-Ding

2012-02-01

This paper reports an application of phase shifted fiber Bragg grating (PS-FBG) intensity-type acoustic sensor in a continuous and in-situ failure testing of an E-glass/vinylester top hat stiffener (THS). The narrow transmission channel of the PS-FBG is highly sensitive to small perturbation, hence suitable to be used in an effective acoustic emission (AE) assessment technique. The progressive failure of THS was tested under transverse loading to experimentally simulate the actual loading in practice. Our experimental tests have demonstrated, in good agreement with the commercial piezoelectric sensors, that the important failures information of the THS was successfully recorded by the simple intensity-type PS-FBG sensor.

Cross-Cultural Adaptation and Psychometric Testing of the Brazilian Version of the Self-Care of Heart Failure Index Version 6.2

PubMed Central

Ávila, Christiane Wahast; Riegel, Barbara; Pokorski, Simoni Chiarelli; Camey, Suzi; Silveira, Luana Claudia Jacoby; Rabelo-Silva, Eneida Rejane

2013-01-01

Objective. To adapt and evaluate the psychometric properties of the Brazilian version of the SCHFI v 6.2. Methods. With the approval of the original author, we conducted a complete cross-cultural adaptation of the instrument (translation, synthesis, back translation, synthesis of back translation, expert committee review, and pretesting). The adapted version was named Brazilian version of the self-care of heart failure index v 6.2. The psychometric properties assessed were face validity and content validity (by expert committee review), construct validity (convergent validity and confirmatory factor analysis), and reliability. Results. Face validity and content validity were indicative of semantic, idiomatic, experimental, and conceptual equivalence. Convergent validity was demonstrated by a significant though moderate correlation (r = −0.51) on comparison with equivalent question scores of the previously validated Brazilian European heart failure self-care behavior scale. Confirmatory factor analysis supported the original three-factor model as having the best fit, although similar results were obtained for inadequate fit indices. The reliability of the instrument, as expressed by Cronbach's alpha, was 0.40, 0.82, and 0.93 for the self-care maintenance, self-care management, and self-care confidence scales, respectively. Conclusion. The SCHFI v 6.2 was successfully adapted for use in Brazil. Nevertheless, further studies should be carried out to improve its psychometric properties. PMID:24163765

Heart Rate Dynamics During A Treadmill Cardiopulmonary Exercise Test in Optimized Beta-Blocked Heart Failure Patients

PubMed Central

Carvalho, Vitor Oliveira; Guimarães, Guilherme Veiga; Ciolac, Emmanuel Gomes; Bocchi, Edimar Alcides

2008-01-01

BACKGROUND Calculating the maximum heart rate for age is one method to characterize the maximum effort of an individual. Although this method is commonly used, little is known about heart rate dynamics in optimized beta-blocked heart failure patients. AIM The aim of this study was to evaluate heart rate dynamics (basal, peak and % heart rate increase) in optimized beta-blocked heart failure patients compared to sedentary, normal individuals (controls) during a treadmill cardiopulmonary exercise test. METHODS Twenty-five heart failure patients (49±11 years, 76% male), with an average LVEF of 30±7%, and fourteen controls were included in the study. Patients with atrial fibrillation, a pacemaker or noncardiovascular functional limitations or whose drug therapy was not optimized were excluded. Optimization was considered to be 50 mg/day or more of carvedilol, with a basal heart rate between 50 to 60 bpm that was maintained for 3 months. RESULTS Basal heart rate was lower in heart failure patients (57±3 bpm) compared to controls (89±14 bpm; p<0.0001). Similarly, the peak heart rate (% maximum predicted for age) was lower in HF patients (65.4±11.1%) compared to controls (98.6±2.2; p<0.0001). Maximum respiratory exchange ratio did not differ between the groups (1.2±0.5 for controls and 1.15±1 for heart failure patients; p=0.42). All controls reached the maximum heart rate for their age, while no patients in the heart failure group reached the maximum. Moreover, the % increase of heart rate from rest to peak exercise between heart failure (48±9%) and control (53±8%) was not different (p=0.157). CONCLUSION No patient in the heart failure group reached the maximum heart rate for their age during a treadmill cardiopulmonary exercise test, despite the fact that the percentage increase of heart rate was similar to sedentary normal subjects. A heart rate increase in optimized beta-blocked heart failure patients during cardiopulmonary exercise test over 65% of the

Validation through Understanding Test-Taking Strategies: An Illustration With the CELPIP-General Reading Pilot Test Using Structural Equation Modeling

ERIC Educational Resources Information Center

Wu, Amery D.; Stone, Jake E.

2016-01-01

This article explores an approach for test score validation that examines test takers' strategies for taking a reading comprehension test. The authors formulated three working hypotheses about score validity pertaining to three types of test-taking strategy (comprehending meaning, test management, and test-wiseness). These hypotheses were…

Test of a Dignity Model in patients with heart failure.

PubMed

Bagheri, Hossein; Yaghmaei, Farideh; Ashktorab, Tahereh; Zayeri, Farid

2018-06-01

Identifying, maintenance, and promotion of dignity in different patients of various cultures is an ethical responsibility of healthcare workers. This study was conducted to investigate factors related to dignity in patients with heart failure and test the validity of Dignity Model. The study had a descriptive-correlational design, and data collection was carried out by means of four specific questionnaires. Participants and context: A total of 130 in-patients from cardiac wards in hospitals affiliated with Tehran and Shahid Beheshti University of Medical Sciences participated. Ethical consideration: This study was approved by the Research Committee of Shahid Beheshti University of Medical Sciences. Significant correlation showed the following: between illness related worries with dignity conserving repertoire score, between illness related worries with social dignity, between illness related worries with dignity conserving repertoire score, and between social dignity with dignity score. Goodness Fit Index and Comparative Fit Index were calculated greater than 0.9. This study affirms the importance of careful evaluation of individual patients to determine their needs related to dignity. According to the results, the necessity of using appropriate tools to assess various aspects of patients' dignity by clinical healthcare staff and design activities with particular focus on the main factors affecting dignity such as illness related worries and social dignity is recommended. Attention to this issue in everyday clinical practice can facilitate health professionals/nurses to potentially improve their patients' dignity, develop quality of care and treatment, and improve patients' satisfaction.

Creep test observation of viscoelastic failure of edible fats

NASA Astrophysics Data System (ADS)

Vithanage, C. R.; Grimson, M. J.; Smith, B. G.; Wills, P. R.

2011-03-01

A rheological creep test was used to investigate the viscoelastic failure of five edible fats. Butter, spreadable blend and spread were selected as edible fats because they belong to three different groups according to the Codex Alimentarius. Creep curves were analysed according to the Burger model. Results were fitted to a Weibull distribution representing the strain-dependent lifetime of putative fibres in the material. The Weibull shape and scale (lifetime) parameters were estimated for each substance. A comparison of the rheometric measurements of edible fats demonstrated a clear difference between the three different groups. Taken together the results indicate that butter has a lower threshold for mechanical failure than spreadable blend and spread. The observed behaviour of edible fats can be interpreted using a model in which there are two types of bonds between fat crystals; primary bonds that are strong and break irreversibly, and secondary bonds, which are weaker but break and reform reversibly.

The Anomalous Sentences Repetition Test: Replication and Validation Study.

ERIC Educational Resources Information Center

Weeks, David J.

1986-01-01

Presents a brief clinical test, derived from earlier neuropsychological instruments, with evidence for its reliability, interscorer agreement, and validity. The latter is based upon correlations with both CAT scan measures of cortical atrophy and ventricular enlargement, as well as correlations with seven other previously validated cognitive…

Reliability and Validity of the Inline Skating Skill Test

PubMed Central

Radman, Ivan; Ruzic, Lana; Padovan, Viktoria; Cigrovski, Vjekoslav; Podnar, Hrvoje

2016-01-01

This study aimed to examine the reliability and validity of the inline skating skill test. Based on previous skating experience forty-two skaters (26 female and 16 male) were randomized into two groups (competitive level vs. recreational level). They performed the test four times, with a recovery time of 45 minutes between sessions. Prior to testing, the participants rated their skating skill using a scale from 1 to 10. The protocol included performance time measurement through a course, combining different skating techniques. Trivial changes in performance time between the repeated sessions were determined in both competitive females/males and recreational females/males (-1.7% [95% CI: -5.8–2.6%] – 2.2% [95% CI: 0.0–4.5%]). In all four subgroups, the skill test had a low mean within-individual variation (1.6% [95% CI: 1.2–2.4%] – 2.7% [95% CI: 2.1–4.0%]) and high mean inter-session correlation (ICC = 0.97 [95% CI: 0.92–0.99] – 0.99 [95% CI: 0.98–1.00]). The comparison of detected typical errors and smallest worthwhile changes (calculated as standard deviations × 0.2) revealed that the skill test was able to track changes in skaters’ performances. Competitive-level skaters needed shorter time (24.4–26.4%, all p < 0.01) to complete the test in comparison to recreational-level skaters. Moreover, moderate correlation (ρ = 0.80–0.82; all p < 0.01) was observed between the participant’s self-rating and achieved performance times. In conclusion, the proposed test is a reliable and valid method to evaluate inline skating skills in amateur competitive and recreational level skaters. Further studies are needed to evaluate the reproducibility of this skill test in different populations including elite inline skaters. Key points Study evaluated the reliability and construct validity of a newly developed inline skating skill test. Evaluated test is a first protocol designed to assess specific inline skating skill. Two groups of amateur skaters with

Performance Validity Testing in Neuropsychology: Scientific Basis and Clinical Application-A Brief Review.

PubMed

Greher, Michael R; Wodushek, Thomas R

2017-03-01

Performance validity testing refers to neuropsychologists' methodology for determining whether neuropsychological test performances completed in the course of an evaluation are valid (ie, the results of true neurocognitive function) or invalid (ie, overly impacted by the patient's effort/engagement in testing). This determination relies upon the use of either standalone tests designed for this sole purpose, or specific scores/indicators embedded within traditional neuropsychological measures that have demonstrated this utility. In response to a greater appreciation for the critical role that performance validity issues play in neuropsychological testing and the need to measure this variable to the best of our ability, the scientific base for performance validity testing has expanded greatly over the last 20 to 30 years. As such, the majority of current day neuropsychologists in the United States use a variety of measures for the purpose of performance validity testing as part of everyday forensic and clinical practice and address this issue directly in their evaluations. The following is the first article of a 2-part series that will address the evolution of performance validity testing in the field of neuropsychology, both in terms of the science as well as the clinical application of this measurement technique. The second article of this series will review performance validity tests in terms of methods for development of these measures, and maximizing of diagnostic accuracy.

Emergency Heart Failure Mortality Risk Grade score performance for 7-day mortality prediction in patients with heart failure attended at the emergency department: validation in a Spanish cohort.

PubMed

Gil, Víctor; Miró, Òscar; Schull, Michael J; Llorens, Pere; Herrero-Puente, Pablo; Jacob, Javier; Ríos, José; Lee, Douglas S; Martín-Sánchez, Francisco J

2018-06-01

The Emergency Heart Failure Mortality Risk Grade (EHMRG) scale, derived in 86 Canadian emergency departments (EDs), stratifies patients with acute-decompensated heart failure (ADHF) according to their 7-day mortality risk. We evaluated its external validity in a Spanish cohort. We applied the EHMRG scale to ADHF patients consecutively included in the Epidemiology of Acute Heart Failure in Emergency departments (EAHFE) registry (29 Spanish EDs) and measured its performance. Patients were distributed into quintiles according to the original and their self-defined score cutoffs. The 7-day mortality rates were compared internally among different categories and with categories of Canadian cohorts. The EAHFE group [n: 1553 patients; 80 (10) years; 55.6% women] had a 5.5% 7-day mortality rate and the EHMRG scale c-statistic was 0.741 (95% confidence interval: 0.688-0.793) compared with 0.807 (0.761-0.842) and 0.804 (0.763-0.840) obtained in the Canadian derivation and validation cohorts. The mortality rate of the EAHFE group mortality increased progressively as the quintile categories increased using intervals defined by either the Canadian or the Spanish EHMRG score cutoffs, although with more regular increments with the EAHFE-defined intervals; using the latter, patients at quintiles 2, 3, 4, 5a and 5b had (compared with quintile 1) odds ratios of 1.77, 3.36, 4.44, 9.39 and 16.19, respectively. The EHMRG scale stratified risk in an ADHF cohort that included both palliative and nonpalliative patients in Spanish EDs, showing an extrapolation to a higher mortality risk cohort than the original derivation sample. Stratification improved when the score was recalibrated in the Spanish cohort.

Validity of the Eating Attitude Test among Exercisers.

PubMed

Lane, Helen J; Lane, Andrew M; Matheson, Hilary

2004-12-01

Theory testing and construct measurement are inextricably linked. To date, no published research has looked at the factorial validity of an existing eating attitude inventory for use with exercisers. The Eating Attitude Test (EAT) is a 26-item measure that yields a single index of disordered eating attitudes. The original factor analysis showed three interrelated factors: Dieting behavior (13-items), oral control (7-items), and bulimia nervosa-food preoccupation (6-items). The primary purpose of the study was to examine the factorial validity of the EAT among a sample of exercisers. The second purpose was to investigate relationships between eating attitudes scores and selected psychological constructs. In stage one, 598 regular exercisers completed the EAT. Confirmatory factor analysis (CFA) was used to test the single-factor, a three-factor model, and a four-factor model, which distinguished bulimia from food pre-occupation. CFA of the single-factor model (RCFI = 0.66, RMSEA = 0.10), the three-factor-model (RCFI = 0.74; RMSEA = 0.09) showed poor model fit. There was marginal fit for the 4-factor model (RCFI = 0.91, RMSEA = 0.06). Results indicated five-items showed poor factor loadings. After these 5-items were discarded, the three models were re-analyzed. CFA results indicated that the single-factor model (RCFI = 0.76, RMSEA = 0.10) and three-factor model (RCFI = 0.82, RMSEA = 0.08) showed poor fit. CFA results for the four-factor model showed acceptable fit indices (RCFI = 0.98, RMSEA = 0.06). Stage two explored relationships between EAT scores, mood, self-esteem, and motivational indices toward exercise in terms of self-determination, enjoyment and competence. Correlation results indicated that depressed mood scores positively correlated with bulimia and dieting scores. Further, dieting was inversely related with self-determination toward exercising. Collectively, findings suggest that a 21-item four-factor model shows promising validity coefficients among

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.

K(3)EDTA Vacuum Tubes Validation for Routine Hematological Testing.

PubMed

Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Poli, Giovanni; Solero, Giovanni Pietro; Picheth, Geraldo; Guidi, Gian Cesare

2012-01-01

Background and Objective. Some in vitro diagnostic devices (e.g, blood collection vacuum tubes and syringes for blood analyses) are not validated before the quality laboratory managers decide to start using or to change the brand. Frequently, the laboratory or hospital managers select the vacuum tubes for blood collection based on cost considerations or on relevance of a brand. The aim of this study was to validate two dry K(3)EDTA vacuum tubes of different brands for routine hematological testing. Methods. Blood specimens from 100 volunteers in two different K(3)EDTA vacuum tubes were collected by a single, expert phlebotomist. The routine hematological testing was done on Advia 2120i hematology system. The significance of the differences between samples was assessed by paired Student's t-test after checking for normality. The level of statistical significance was set at P < 0.05. Results and Conclusions. Different brand's tubes evaluated can represent a clinically relevant source of variations only on mean platelet volume (MPV) and platelet distribution width (PDW). Basically, our validation will permit the laboratory or hospital managers to select the brand's vacuum tubes validated according to him/her technical or economical reasons for routine hematological tests.

Commentary on "Validating the Interpretations and Uses of Test Scores"

ERIC Educational Resources Information Center

Brennan, Robert L.

2013-01-01

Kane's paper "Validating the Interpretations and Uses of Test Scores" is the most complete and clearest discussion yet available of the argument-based approach to validation. At its most basic level, validation as formulated by Kane is fundamentally a simply-stated two-step enterprise: (1) specify the claims inherent in a particular interpretation…

ExEP yield modeling tool and validation test results

NASA Astrophysics Data System (ADS)

Morgan, Rhonda; Turmon, Michael; Delacroix, Christian; Savransky, Dmitry; Garrett, Daniel; Lowrance, Patrick; Liu, Xiang Cate; Nunez, Paul

2017-09-01

EXOSIMS is an open-source simulation tool for parametric modeling of the detection yield and characterization of exoplanets. EXOSIMS has been adopted by the Exoplanet Exploration Programs Standards Definition and Evaluation Team (ExSDET) as a common mechanism for comparison of exoplanet mission concept studies. To ensure trustworthiness of the tool, we developed a validation test plan that leverages the Python-language unit-test framework, utilizes integration tests for selected module interactions, and performs end-to-end crossvalidation with other yield tools. This paper presents the test methods and results, with the physics-based tests such as photometry and integration time calculation treated in detail and the functional tests treated summarily. The test case utilized a 4m unobscured telescope with an idealized coronagraph and an exoplanet population from the IPAC radial velocity (RV) exoplanet catalog. The known RV planets were set at quadrature to allow deterministic validation of the calculation of physical parameters, such as working angle, photon counts and integration time. The observing keepout region was tested by generating plots and movies of the targets and the keepout zone over a year. Although the keepout integration test required the interpretation of a user, the test revealed problems in the L2 halo orbit and the parameterization of keepout applied to some solar system bodies, which the development team was able to address. The validation testing of EXOSIMS was performed iteratively with the developers of EXOSIMS and resulted in a more robust, stable, and trustworthy tool that the exoplanet community can use to simulate exoplanet direct-detection missions from probe class, to WFIRST, up to large mission concepts such as HabEx and LUVOIR.

Testing-Based Compiler Validation for Synchronous Languages

NASA Technical Reports Server (NTRS)

Garoche, Pierre-Loic; Howar, Falk; Kahsai, Temesghen; Thirioux, Xavier

2014-01-01

In this paper we present a novel lightweight approach to validate compilers for synchronous languages. Instead of verifying a compiler for all input programs or providing a fixed suite of regression tests, we extend the compiler to generate a test-suite with high behavioral coverage and geared towards discovery of faults for every compiled artifact. We have implemented and evaluated our approach using a compiler from Lustre to C.

Composite Failures: A Comparison of Experimental Test Results and Computational Analysis Using XFEM

DTIC Science & Technology

2016-09-30

NUWC-NPT Technical Report 12,218 30 September 2016 Composite Failures: A Comparison of Experimental Test Results and Computational Analysis...A Comparison of Experimental Test Results and Computational Analysis Using XFEM 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...availability of measurement techniques, experimental testing of composite materials has largely outpaced the computational modeling ability, forcing

B-type natriuretic peptide testing for detection of heart failure.

PubMed

Saul, Lauren; Shatzer, Melanie

2003-01-01

The incidence of heart failure (HF) is on the increase with the aging population. Heart failure can manifest as either systolic or diastolic dysfunction. Systolic dysfunction causes impaired ventricular contractility with an ejection fraction of less than 45%. In contrast, diastolic dysfunction is evidenced by impaired ventricular relaxation and an ejection fraction greater than 45%. The diagnosis of HF is challenging with patients who present with acute dyspnea and a history of chronic obstructive pulmonary disease or pneumonia. The pathophysiology of HF and the resulting compensatory mechanisms involve a complex neuroendocrine response that includes a release of natriuretic peptides including B-type natriuretic peptides (BNPs). Elevation of BNP is in response to ventricular wall stress and volume overload from HF. BNP promotes natriuresis, diuresis, and vasodilitation and therefore counteracts some of the deleterious effects of the neuroendocrine response in HF Recently, a new laboratory test for BNP has been developed to assist in rapid identification of patients with HF. Research studies have shown that BNP testing assists in differentiating between cardiac and pulmonary causes of acute dyspnea and could be used to evaluate effectiveness of therapy and as a predictor for length of stay and readmission.

Validation of the Information/Communications Technology Literacy Test

DTIC Science & Technology

2016-10-01

nested set. Table 11 presents the results of incremental validity analyses for job knowledge/performance criteria by MOS. Figure 7 presents much...Systems Operator-Analyst (25B) and Nodal Network Systems Operator-Maintainer (25N) MOS. This report documents technical procedures and results of the...research effort. Results suggest that the ICTL test has potential as a valid and highly efficient predictor of valued outcomes in Signal school MOS. Not

Validation of Metagenomic Next-Generation Sequencing Tests for Universal Pathogen Detection.

PubMed

Schlaberg, Robert; Chiu, Charles Y; Miller, Steve; Procop, Gary W; Weinstock, George

2017-06-01

- Metagenomic sequencing can be used for detection of any pathogens using unbiased, shotgun next-generation sequencing (NGS), without the need for sequence-specific amplification. Proof-of-concept has been demonstrated in infectious disease outbreaks of unknown causes and in patients with suspected infections but negative results for conventional tests. Metagenomic NGS tests hold great promise to improve infectious disease diagnostics, especially in immunocompromised and critically ill patients. - To discuss challenges and provide example solutions for validating metagenomic pathogen detection tests in clinical laboratories. A summary of current regulatory requirements, largely based on prior guidance for NGS testing in constitutional genetics and oncology, is provided. - Examples from 2 separate validation studies are provided for steps from assay design, and validation of wet bench and bioinformatics protocols, to quality control and assurance. - Although laboratory and data analysis workflows are still complex, metagenomic NGS tests for infectious diseases are increasingly being validated in clinical laboratories. Many parallels exist to NGS tests in other fields. Nevertheless, specimen preparation, rapidly evolving data analysis algorithms, and incomplete reference sequence databases are idiosyncratic to the field of microbiology and often overlooked.

Could Acoustic Emission Testing Show a Pipe Failure in Advance?

NASA Astrophysics Data System (ADS)

Soares, S. D.; Teixeira, J. C. G.

2004-02-01

During the last 20 years PETROBRAS has been attempting to use Acoustic Emission (AE) as an inspection tool. In this period the AE concept has changed from a revolutionary method to a way of finding areas to make a complete inspection. PETROBRAS has a lot of pressure vessels inspected by AE and with other NDTs techniques to establish their relationship. In other hand, PETROBRAS R&D Center has conducted destructive hydrostatic tests in pipelines samples with artificial defects made by milling. Those tests were monitored by acoustic emission and manual ultrasonic until the complete failure of pipe sample. This article shows the results obtained and a brief proposal of analysis criteria for this environment of test.

Development and Validation of a Test for Bulimia.

ERIC Educational Resources Information Center

Smith, Marcia C.; Thelen, Mark H.

1984-01-01

Developed the Bulimia Test (BULIT) based on responses of clinically identified females (N=18) and normal female college students (N=119) to preliminary test items. Results showed that the BULIT provided an objective, reliable, and valid measure by which to identify individuals with symptoms of bulimia. (Instrument is appended.) (LLL)

Does the 6-minute walk test predict the prognosis in patients with NYHA class II or III chronic heart failure?

PubMed

Roul, G; Germain, P; Bareiss, P

1998-09-01

We prospectively evaluated the potential of the 6-minute walk test compared with peak VO2 in predicting outcome of patients with New York Heart Association (NYHA) class II or III heart failure. Patients with a history of heart failure caused by systolic dysfunction were included. The combined final outcome (death or hospitalization for heart failure) was used as the judgment criterion. One hundred twenty-one patients (age 59+/-11 years; left ventricular ejection fraction 29.6%+/-13%) were included and followed for 1.53+/-0.98 years. Patients were separated into two groups according to outcome: group 1 (G1, 74 patients), without events, and group 2 (G2, 47 patients), who reached the combined end point. Peak VO2 was clearly different between G1 and G2 (18.5+/-4 vs. 13.9+/-4 ml/kg/min, p=0.0001) but not the distance walked (448+/-92 vs 410+/-126 m; p=0.084, not significant). Survival analysis showed that unlike peak VO2, the distance covered was barely distinguishable between the groups (p < 0.08). However, receiver operating characteristic curves revealed that the best performances for the 6-minute walk test were obtained for subjects walking < or =300 m. These patients had a worse prognosis than those walking farther (p=0.013). In this subset of patients, there was a significant correlation between distance covered and peak VO2 (r=0.65, p=0.011). Thus it appears that the more severely affected patients have a daily activity level relatively close to their maximal exercise capacity. Nevertheless, the 300 m threshold suggested by this study needs to be validated in an independent population. A distance walked in 6 minutes < or =300 m can predict outcome. Moreover, in these cases there is a significant correlation between the 6-minute walk test and peak VO2 demonstrating the potential of this simple procedure as a first-line screening test for this subset of patients.

Strategies for Validation Testing of Ground Systems

NASA Technical Reports Server (NTRS)

Annis, Tammy; Sowards, Stephanie

2009-01-01

In order to accomplish the full Vision for Space Exploration announced by former President George W. Bush in 2004, NASA will have to develop a new space transportation system and supporting infrastructure. The main portion of this supporting infrastructure will reside at the Kennedy Space Center (KSC) in Florida and will either be newly developed or a modification of existing vehicle processing and launch facilities, including Ground Support Equipment (GSE). This type of large-scale launch site development is unprecedented since the time of the Apollo Program. In order to accomplish this successfully within the limited budget and schedule constraints a combination of traditional and innovative strategies for Verification and Validation (V&V) have been developed. The core of these strategies consists of a building-block approach to V&V, starting with component V&V and ending with a comprehensive end-to-end validation test of the complete launch site, called a Ground Element Integration Test (GEIT). This paper will outline these strategies and provide the high level planning for meeting the challenges of implementing V&V on a large-scale development program. KEY WORDS: Systems, Elements, Subsystem, Integration Test, Ground Systems, Ground Support Equipment, Component, End Item, Test and Verification Requirements (TVR), Verification Requirements (VR)

Automated Vision Test Development and Validation

DTIC Science & Technology

2016-11-01

Deputy Chief, Aerosp Med Consultation Div Chair, Aerospace Medicine Department This report is published in the interest of...produce software for desktop displays; and to evaluate features such as user interfaces, threshold algorithms, validity of results, and screening...cost of performing full threshold testing on over 30% of normal subjects, which is quite time consuming. This effort was accomplished using desktop

Development and pilot testing of a disease management program for low literacy patients with heart failure.

PubMed

DeWalt, Darren A; Pignone, Michael; Malone, Robb; Rawls, Cathy; Kosnar, Margaret C; George, Geeta; Bryant, Betsy; Rothman, Russell L; Angel, Bonnie

2004-10-01

Development and pilot testing of a disease management program for low literacy patients with heart failure. Randomized trials have shown that disease management programs can reduce hospitalizations and improve symptoms for patients with congestive heart failure. We sought to create and pilot test such a program for patients with low literacy skills. We used focus groups and individual cognitive response interviews (CRIs) to develop an educational booklet for low literacy patients with heart failure. We incorporated the booklet into a disease management intervention that also included an initial individualized 1-h educational session and scheduled supportive phone calls that were tapered over 6 weeks. We then conducted a 3-month before-after study on patients with low literacy skills (<9th grade literacy level) in a university internal medicine clinic to test the acceptability and efficacy of our program. Outcomes of interest included heart failure-related knowledge, self-care behavior and heart failure-related symptoms measured on the Minnesota Living with Heart Failure (MLwHF) scale. Twenty-five patients were enrolled and 23 (92%) completed 3-month follow-up. Mean age was 60 years (range 35-74), 60% were men, 60% were African-American, and 74% had household income under $15,000 per year. The median reading level was fifth grade with 32% reading at or below the third grade level. Mean knowledge score at baseline was 67% and did not improve after the intervention. The proportion of patients reporting weighing themselves daily increased from 32% at baseline to 100% at 12 weeks. Mean improvement on the MLwHF scale was 9.9 points over the 3-month trial (95% CI: 0.5, 19.2), which corresponds to an improvement in one class on the New York Heart Association heart failure scale. A heart failure disease management program designed specifically for patients with low literacy skills is acceptable and is associated with improvement in self-care behavior and heart failure

Validation of the Vanderbilt Holistic Face Processing Test.

PubMed

Wang, Chao-Chih; Ross, David A; Gauthier, Isabel; Richler, Jennifer J

2016-01-01

The Vanderbilt Holistic Face Processing Test (VHPT-F) is a new measure of holistic face processing with better psychometric properties relative to prior measures developed for group studies (Richler et al., 2014). In fields where psychologists study individual differences, validation studies are commonplace and the concurrent validity of a new measure is established by comparing it to an older measure with established validity. We follow this approach and test whether the VHPT-F measures the same construct as the composite task, which is group-based measure at the center of the large literature on holistic face processing. In Experiment 1, we found a significant correlation between holistic processing measured in the VHPT-F and the composite task. Although this correlation was small, it was comparable to the correlation between holistic processing measured in the composite task with the same faces, but different target parts (top or bottom), which represents a reasonable upper limit for correlations between the composite task and another measure of holistic processing. These results confirm the validity of the VHPT-F by demonstrating shared variance with another measure of holistic processing based on the same operational definition. These results were replicated in Experiment 2, but only when the demographic profile of our sample matched that of Experiment 1.

Validation of the Vanderbilt Holistic Face Processing Test

PubMed Central

Wang, Chao-Chih; Ross, David A.; Gauthier, Isabel; Richler, Jennifer J.

2016-01-01

The Vanderbilt Holistic Face Processing Test (VHPT-F) is a new measure of holistic face processing with better psychometric properties relative to prior measures developed for group studies (Richler et al., 2014). In fields where psychologists study individual differences, validation studies are commonplace and the concurrent validity of a new measure is established by comparing it to an older measure with established validity. We follow this approach and test whether the VHPT-F measures the same construct as the composite task, which is group-based measure at the center of the large literature on holistic face processing. In Experiment 1, we found a significant correlation between holistic processing measured in the VHPT-F and the composite task. Although this correlation was small, it was comparable to the correlation between holistic processing measured in the composite task with the same faces, but different target parts (top or bottom), which represents a reasonable upper limit for correlations between the composite task and another measure of holistic processing. These results confirm the validity of the VHPT-F by demonstrating shared variance with another measure of holistic processing based on the same operational definition. These results were replicated in Experiment 2, but only when the demographic profile of our sample matched that of Experiment 1. PMID:27933014

Reliability and validity of the closed kinetic chain upper extremity stability test.

PubMed

Lee, Dong-Rour; Kim, Laurentius Jongsoon

2015-04-01

[Purpose] The purpose of this study was to examine the reliability and validity of the Closed Kinetic Chain Upper Extremity Stability (CKCUES) test. [Subjects and Methods] A sample of 40 subjects (20 males, 20 females) with and without pain in the upper limbs was recruited. The subjects were tested twice, three days apart to assess the reliability of the CKCUES test. The CKCUES test was performed four times, and the average was calculated using the data of the last 3 tests. In order to test the validity of the CKCUES test, peak torque of internal/external shoulder rotation was measured using an isokinetic dynamometer, and maximum grip strength was measured using a hand dynamometer, and their Pearson correlation coefficients with the average values of the CKCUES test were calculated. [Results] The reliability of the CKCUES test was very high (ICC=0.97). The correlations between the CKCUES test and maximum grip strength (r=0.78-0.79), and the peak torque of internal/external shoulder rotation (r=0.87-0.94) were high indicating its validity. [Conclusion] The reliability and validity of the CKCUES test were high. The CKCUES test is expected to be used for clinical tests on upper limb stability at low price.

Validity Tests of the Adolescent Domain Screening Inventory (ADSI) with Older Adolescents

ERIC Educational Resources Information Center

Corrigan, Matthew J.; Forte, James; Bulgaris, Sarah

2017-01-01

The purpose of this replication study is to test the validity of the Adolescent Domain Screening Inventory (ADSI) on an older adolescent population. This cross sectional study used a convenience sample to preliminarily test the validity of the ADSI. Concurrent validity correlations ranged from a high of 0.924 to a low of 0.760. The known…

Validity Theory: Reform Policies, Accountability Testing, and Consequences

ERIC Educational Resources Information Center

Chalhoub-Deville, Micheline

2016-01-01

Educational policies such as Race to the Top in the USA affirm a central role for testing systems in government-driven reform efforts. Such reform policies are often referred to as the global education reform movement (GERM). Changes observed with the GERM style of testing demand socially engaged validity theories that include consequential…

Validity of Integrity Tests for Predicting Drug and Alcohol Abuse

DTIC Science & Technology

1993-08-31

Wiinkler and Sheridan (1989) found that employees who entered employee assistance programs for treating drug addiction were more likely be absent...August 31, 1993 Final 4. TITLE AND SUBTITLE S. FUNDING NUMBERS Validity of Integrity Tests for Predicting Drug and Alcohol Abuse C No. N00014-92-J...words) This research used psychometric meta-analysis (Hunter & Schmidt, 1990b) to examine the validity of integrity tests for predicting drug and

Validation of a clinical critical thinking skills test in nursing.

PubMed

Shin, Sujin; Jung, Dukyoo; Kim, Sungeun

2015-01-27

The purpose of this study was to develop a revised version of the clinical critical thinking skills test (CCTS) and to subsequently validate its performance. This study is a secondary analysis of the CCTS. Data were obtained from a convenience sample of 284 college students in June 2011. Thirty items were analyzed using item response theory and test reliability was assessed. Test-retest reliability was measured using the results of 20 nursing college and graduate school students in July 2013. The content validity of the revised items was analyzed by calculating the degree of agreement between instrument developer intention in item development and the judgments of six experts. To analyze response process validity, qualitative data related to the response processes of nine nursing college students obtained through cognitive interviews were analyzed. Out of initial 30 items, 11 items were excluded after the analysis of difficulty and discrimination parameter. When the 19 items of the revised version of the CCTS were analyzed, levels of item difficulty were found to be relatively low and levels of discrimination were found to be appropriate or high. The degree of agreement between item developer intention and expert judgments equaled or exceeded 50%. From above results, evidence of the response process validity was demonstrated, indicating that subjects respondeds as intended by the test developer. The revised 19-item CCTS was found to have sufficient reliability and validity and will therefore represents a more convenient measurement of critical thinking ability.

Development and Validity Testing of an Arthritis Self-Management Assessment Tool.

PubMed

Oh, HyunSoo; Han, SunYoung; Kim, SooHyun; Seo, WhaSook

Because of the chronic, progressive nature of arthritis and the substantial effects it has on quality of life, patients may benefit from self-management. However, no valid, reliable self-management assessment tool has been devised for patients with arthritis. This study was conducted to develop a comprehensive self-management assessment tool for patients with arthritis, that is, the Arthritis Self-Management Assessment Tool (ASMAT). To develop a list of qualified items corresponding to the conceptual definitions and attributes of arthritis self-management, a measurement model was established on the basis of theoretical and empirical foundations. Content validity testing was conducted to evaluate whether listed items were suitable for assessing arthritis self-management. Construct validity and reliability of the ASMAT were tested. Construct validity was examined using confirmatory factor analysis and nomological validity. The 32-item ASMAT was developed with a sample composed of patients in a clinic in South Korea. Content validity testing validated the 32 items, which comprised medical (10 items), behavioral (13 items), and psychoemotional (9 items) management subscales. Construct validity testing of the ASMAT showed that the 32 items properly corresponded with conceptual constructs of arthritis self-management, and were suitable for assessing self-management ability in patients with arthritis. Reliability was also well supported. The ASMAT devised in the present study may aid the evaluation of patient self-management ability and the effectiveness of self-management interventions. The authors believe the developed tool may also aid the identification of problems associated with the adoption of self-management practice, and thus improve symptom management, independence, and quality of life of patients with arthritis.

Validation of Heart Failure Events in the Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) Participants Assigned to Doxazosin and Chlorthalidone

PubMed Central

Piller, Linda B; Davis, Barry R; Cutler, Jeffrey A; Cushman, William C; Wright, Jackson T; Williamson, Jeff D; Leenen, Frans HH; Einhorn, Paula T; Randall, Otelio S; Golden, John S; Haywood, L Julian

2002-01-01

Background The Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) is a randomized, double-blind, active-controlled trial designed to compare the rate of coronary heart disease events in high-risk hypertensive participants initially randomized to a diuretic (chlorthalidone) versus each of three alternative antihypertensive drugs: alpha-adrenergic blocker (doxazosin), ACE-inhibitor (lisinopril), and calcium-channel blocker (amlodipine). Combined cardiovascular disease risk was significantly increased in the doxazosin arm compared to the chlorthalidone arm (RR 1.25; 95% CI, 1.17–1.33; P < .001), with a doubling of heart failure (fatal, hospitalized, or non-hospitalized but treated) (RR 2.04; 95% CI, 1.79–2.32; P < .001). Questions about heart failure diagnostic criteria led to steps to validate these events further. Methods and Results Baseline characteristics (age, race, sex, blood pressure) did not differ significantly between treatment groups (P < .05) for participants with heart failure events. Post-event pharmacologic management was similar in both groups and generally conformed to accepted heart failure therapy. Central review of a small sample of cases showed high adherence to ALLHAT heart failure criteria. Of 105 participants with quantitative ejection fraction measurements provided, (67% by echocardiogram, 31% by catheterization), 29/46 (63%) from the chlorthalidone group and 41/59 (70%) from the doxazosin group were at or below 40%. Two-year heart failure case-fatalities (22% and 19% in the doxazosin and chlorthalidone groups, respectively) were as expected and did not differ significantly (RR 0.96; 95% CI, 0.67–1.38; P = 0.83). Conclusion Results of the validation process supported findings of increased heart failure in the ALLHAT doxazosin treatment arm compared to the chlorthalidone treatment arm. PMID:12459039

LADO as a Language Test: Issues of Validity

ERIC Educational Resources Information Center

McNamara, Tim; Van Den Hazelkamp, Carolien; Verrips, Maaike

2016-01-01

This article brings together the theoretical field of language testing and the practical field of language analysis for the determination of the origin of asylum seekers. It considers what it would mean to think of language analysis as a form of language test, subject to the same validity constraints, and proposes a research agenda.

Two-Speed Gearbox Dynamic Simulation Predictions and Test Validation

NASA Technical Reports Server (NTRS)

Lewicki, David G.; DeSmidt, Hans; Smith, Edward C.; Bauman, Steven W.

2010-01-01

Dynamic simulations and experimental validation tests were performed on a two-stage, two-speed gearbox as part of the drive system research activities of the NASA Fundamental Aeronautics Subsonics Rotary Wing Project. The gearbox was driven by two electromagnetic motors and had two electromagnetic, multi-disk clutches to control output speed. A dynamic model of the system was created which included a direct current electric motor with proportional-integral-derivative (PID) speed control, a two-speed gearbox with dual electromagnetically actuated clutches, and an eddy current dynamometer. A six degree-of-freedom model of the gearbox accounted for the system torsional dynamics and included gear, clutch, shaft, and load inertias as well as shaft flexibilities and a dry clutch stick-slip friction model. Experimental validation tests were performed on the gearbox in the NASA Glenn gear noise test facility. Gearbox output speed and torque as well as drive motor speed and current were compared to those from the analytical predictions. The experiments correlate very well with the predictions, thus validating the dynamic simulation methodologies.

K3EDTA Vacuum Tubes Validation for Routine Hematological Testing

PubMed Central

Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Poli, Giovanni; Solero, Giovanni Pietro; Picheth, Geraldo; Guidi, Gian Cesare

2012-01-01

Background and Objective. Some in vitro diagnostic devices (e.g, blood collection vacuum tubes and syringes for blood analyses) are not validated before the quality laboratory managers decide to start using or to change the brand. Frequently, the laboratory or hospital managers select the vacuum tubes for blood collection based on cost considerations or on relevance of a brand. The aim of this study was to validate two dry K3EDTA vacuum tubes of different brands for routine hematological testing. Methods. Blood specimens from 100 volunteers in two different K3EDTA vacuum tubes were collected by a single, expert phlebotomist. The routine hematological testing was done on Advia 2120i hematology system. The significance of the differences between samples was assessed by paired Student's t-test after checking for normality. The level of statistical significance was set at P < 0.05. Results and Conclusions. Different brand's tubes evaluated can represent a clinically relevant source of variations only on mean platelet volume (MPV) and platelet distribution width (PDW). Basically, our validation will permit the laboratory or hospital managers to select the brand's vacuum tubes validated according to him/her technical or economical reasons for routine hematological tests. PMID:22888448

Embedded performance validity tests within the Hopkins Verbal Learning Test - Revised and the Brief Visuospatial Memory Test - Revised.

PubMed

Sawyer, R John; Testa, S Marc; Dux, Moira

2017-01-01

Various research studies and neuropsychology practice organizations have reiterated the importance of developing embedded performance validity tests (PVTs) to detect potentially invalid neurocognitive test data. This study investigated whether measures within the Hopkins Verbal Learning Test - Revised (HVLT-R) and the Brief Visuospatial Memory Test - Revised (BVMT-R) could accurately classify individuals who fail two or more PVTs during routine clinical assessment. The present sample of 109 United States military veterans (Mean age = 52.4, SD = 13.3), all consisted of clinically referred patients and received a battery of neuropsychological tests. Based on performance validity findings, veterans were assigned to valid (n = 86) or invalid (n = 23) groups. Of the 109 patients in the overall sample, 77 were administered the HLVT-R and 75 were administered the BVMT-R, which were examined for classification accuracy. The HVLT-R Recognition Discrimination Index and the BVMT-R Retention Percentage showed good to adequate discrimination with an area under the curve of .78 and .70, respectively. The HVLT-R Recognition Discrimination Index showed sensitivity of .53 with specificity of .93. The BVMT-R Retention Percentage demonstrated sensitivity of .31 with specificity of .92. When used in conjunction with other PVTs, these new embedded PVTs may be effective in the detection of invalid test data, although they are not intended for use in patients with dementia.

The test-retest reliability and criterion validity of a high-intensity, netball-specific circuit test: The Net-Test.

PubMed

Mungovan, Sean F; Peralta, Paula J; Gass, Gregory C; Scanlan, Aaron T

2018-04-12

To examine the test-retest reliability and criterion validity of a high-intensity, netball-specific fitness test. Repeated measures, within-subject design. Eighteen female netball players competing in an international competition completed a trial of the Net-Test, which consists of 14 timed netball-specific movements. Players also completed a series of netball-relevant criterion fitness tests. Ten players completed an additional Net-Test trial one week later to assess test-retest reliability using intraclass correlation coefficient (ICC), typical error of measurement (TEM), and coefficient of variation (CV). The typical error of estimate expressed as CV and Pearson correlations were calculated between each criterion test and Net-Test performance to assess criterion validity. Five movements during the Net-Test displayed moderate ICC (0.84-0.90) and two movements displayed high ICC (0.91-0.93). Seven movements and heart rate taken during the Net-Test held low CV (<5%) with values ranging from 1.7 to 9.5% across measures. Total time (41.63±2.05s) during the Net-Test possessed low CV and significant (p<0.05) correlations with 10m sprint time (1.98±0.12s; CV=4.4%, r=0.72), 20m sprint time (3.38±0.19s; CV=3.9%, r=0.79), 505 Change-of-Direction time (2.47±0.08s; CV=2.0%, r=0.80); and maximum oxygen uptake (46.59±2.58 mLkg -1 min -1 ; CV=4.5%, r=-0.66). The Net-Test possesses acceptable reliability for the assessment of netball fitness. Further, the high criterion validity for the Net-Test suggests a range of important netball-specific fitness elements are assessed in combination. Copyright © 2018 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Validation test of 125 Ah advanced design IPV nickel-hydrogen flight cells

NASA Technical Reports Server (NTRS)

Smithrick, John J.; Hall, Stephen W.

1993-01-01

An update of validation test results confirming the advanced design nickel-hydrogen cell is presented. An advanced 125 Ah individual pressure vessel (IPV) nickel-hydrogen cell was designed. The primary function of the advanced cell is to store and deliver energy for long-term, Low-Earth-Orbit (LEO) spacecraft missions. The new features of this design, which are not incorporated in state-of-the-art design cells, are: (1) use of 26 percent rather than 31 percent potassium hydroxide (KOH) electrolyte; (2) use of a patented catalyzed wall wick; (3) use of serrated-edge separators to facilitate gaseous oxygen and hydrogen flow within the cell, while still maintaining physical contact with the wall wick for electrolyte management; and (4) use of a floating rather than a fixed stack (state-of-the-art) to accommodate nickel electrode expansion due to charge/discharge cycling. The significant improvements resulting from these innovations are extended cycle life; enhanced thermal, electrolyte, and oxygen management; and accommodation of nickel electrode expansion. Six 125 Ah flight cells based on this design were fabricated by Eagle-Picher. Three of the cells contain all of the advanced features (test cells) and three are the same as the test cells except they do not have catalyst on the wall wick (control cells). All six cells are in the process of being evaluated in a LEO cycle life test at the Naval Weapons Support Center, Crane, IN, under a NASA Lewis Research Center contract. The catalyzed wall wick cells have been cycled for over 19000 cycles with no cell failures in the continuing test. Two of the noncatalyzed wall wick cells failed (cycles 9588 and 13,900).

Validity and reliability of the Hawaii anaerobic run test.

PubMed

Kimura, Iris F; Stickley, Christopher D; Lentz, Melissa A; Wages, Jennifer J; Yanagi, Kazuhiko; Hetzler, Ronald K

2014-05-01

This study examined the reliability and validity of the Hawaii anaerobic run test (HART) by comparing anaerobic capacity measures obtained to those during the Wingate Anaerobic Test (WAnT). Ninety-six healthy physically active volunteers (age, 22.0 ± 2.8 years; height, 163.9 ± 9.5 cm; body mass, 70.6 ± 14.7 kg; body fat %, 19.29 ± 5.39%) participated in this study. Each participant performed 2 anaerobic capacity tests: the WAnT and the HART by random assignment on separate days. The reliability of the HART was calculated from 2 separate trials of the test and then determined through intraclass correlation coefficients (ICCs). Blood samples were collected, and lactate was analyzed both pretest and posttest for each of the 2 exercise modes. Heart rate and rate of perceived exertion were also measured pre- and post-exercise. Hawaii anaerobic run test peak and mean momentum were calculated as body mass times highest or average split velocity, respectively. Intraclass correlation coefficients between trials of the HART for peak and mean momentum were 0.98 and 0.99, respectively (SEM = 18.8 and 25.7, respectively). Validity of the HART was established through comparison of momentum on the HART with power on the WAnT. High correlations were found between peak power and peak momentum (r = 0.88), as well as mean power and mean momentum (r = 0.94). The HART was considered to be a reliable test of anaerobic power. The HART was also determined to be a valid test of anaerobic power when compared with the WAnT. When testing healthy college-aged individuals, the HART offers an easy and inexpensive alternative maximal effort anaerobic power test to other established tests.

Kidney Failure and ESRD in the Atherosclerosis Risk in Communities (ARIC) Study: Comparing Ascertainment of Treated and Untreated Kidney Failure in a Cohort Study

PubMed Central

Rebholz, Casey M.; Coresh, Josef; Ballew, Shoshana H.; McMahon, Blaithin; Whelton, Seamus P.; Selvin, Elizabeth; Grams, Morgan E.

2015-01-01

Background Linkage to the US Renal Data System (USRDS) registry is commonly used to identify end-stage renal disease (ESRD) cases, or kidney failure treated with dialysis or transplantation, but it underestimates the total burden of kidney failure. This study validates a kidney failure definition that includes both kidney failure treated and not treated by dialysis or transplantation. It compares kidney failure risk factors and outcomes using this broader definition to USRDS-identified ESRD risk factors and outcomes. Study Design Diagnostic test study with stratified random sampling of hospitalizations for chart review. Setting & Participants Atherosclerosis Risk in Communities Study (N=11,530; chart review n=546). Index Test USRDS-identified ESRD; treated or untreated kidney failure defined by USRDS-identified ESRD or International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)/ICD-10-CM code from hospitalization or death. Reference Test For ESRD, determination of permanent dialysis or transplantation; for kidney failure, determination of permanent dialysis, transplantation, or eGFR <15 mL/min/1.73 m2. Results Over 13 years' median follow-up, 508 kidney failure cases were identified, including 173 (34.1%) from the USRDS registry. ESRD and kidney failure incidence were 1.23 and 3.66 cases per 1,000 person-years in the overall population, and 1.35 and 6.59 cases per 1,000 person-years among participants older than 70 years, respectively. Other risk factor associations were similar between ESRD and kidney failure, except diabetes and albuminuria which were stronger for ESRD. Survival at 1 and 5 years were 74.0% and 24.0% for ESRD and 59.8% and 31.6% for kidney failure, respectively. Sensitivity and specificity were 88.0% and 97.3% comparing the kidney failure ICD-9-CM/ICD-10-CM code algorithm to chart review; for USRDS-identified ESRD, sensitivity and specificity were 94.9% and 100.0%. Limitations Some medical charts were incomplete

Test-Retest Reliability and Predictive Validity of the Implicit Association Test in Children

ERIC Educational Resources Information Center

Rae, James R.; Olson, Kristina R.

2018-01-01

The Implicit Association Test (IAT) is increasingly used in developmental research despite minimal evidence of whether children's IAT scores are reliable across time or predictive of behavior. When test-retest reliability and predictive validity have been assessed, the results have been mixed, and because these studies have differed on many…

Rodent heart failure models do not reflect the human circulating microRNA signature in heart failure.

PubMed

Vegter, Eline L; Ovchinnikova, Ekaterina S; Silljé, Herman H W; Meems, Laura M G; van der Pol, Atze; van der Velde, A Rogier; Berezikov, Eugene; Voors, Adriaan A; de Boer, Rudolf A; van der Meer, Peter

2017-01-01

We recently identified a set of plasma microRNAs (miRNAs) that are downregulated in patients with heart failure in comparison with control subjects. To better understand their meaning and function, we sought to validate these circulating miRNAs in 3 different well-established rat and mouse heart failure models, and correlated the miRNAs to parameters of cardiac function. The previously identified let-7i-5p, miR-16-5p, miR-18a-5p, miR-26b-5p, miR-27a-3p, miR-30e-5p, miR-199a-3p, miR-223-3p, miR-423-3p, miR-423-5p and miR-652-3p were measured by means of quantitative real time polymerase chain reaction (qRT-PCR) in plasma samples of 8 homozygous TGR(mREN2)27 (Ren2) transgenic rats and 8 (control) Sprague-Dawley rats, 6 mice with angiotensin II-induced heart failure (AngII) and 6 control mice, and 8 mice with ischemic heart failure and 6 controls. Circulating miRNA levels were compared between the heart failure animals and healthy controls. Ren2 rats, AngII mice and mice with ischemic heart failure showed clear signs of heart failure, exemplified by increased left ventricular and lung weights, elevated end-diastolic left ventricular pressures, increased expression of cardiac stress markers and reduced left ventricular ejection fraction. All miRNAs were detectable in plasma from rats and mice. No significant differences were observed between the circulating miRNAs in heart failure animals when compared to the healthy controls (all P>0.05) and no robust associations with cardiac function could be found. The previous observation that miRNAs circulate in lower levels in human patients with heart failure could not be validated in well-established rat and mouse heart failure models. These results question the translation of data on human circulating miRNA levels to experimental models, and vice versa the validity of experimental miRNA data for human heart failure.

Pump CFD code validation tests

NASA Technical Reports Server (NTRS)

Brozowski, L. A.

1993-01-01

Pump CFD code validation tests were accomplished by obtaining nonintrusive flow characteristic data at key locations in generic current liquid rocket engine turbopump configurations. Data were obtained with a laser two-focus (L2F) velocimeter at scaled design flow. Three components were surveyed: a 1970's-designed impeller, a 1990's-designed impeller, and a four-bladed unshrouded inducer. Two-dimensional velocities were measured upstream and downstream of the two impellers. Three-dimensional velocities were measured upstream, downstream, and within the blade row of the unshrouded inducer.

Ampoule failure sensor time response testing: Experiment 1

NASA Technical Reports Server (NTRS)

Johnson, M. L.; Watring, D. A.

1994-01-01

The response time of an ampoule failure sensor exposed to a liquid or vapor gallium-arsenide (GaAs) is investigated. The experimental configuration represents the sample/ampoule cartridge assembly used in NASA's Crystal Growth Furnace (CGF). The sensor is a chemical fuse made from a metal with which the semiconductor material reacts more rapidly than it does with the containing cartridge. For the III-IV compound of GaAs, a platinum metal was chosen based on the reaction of platinum and arsenic at elevated temperatures which forms a low melting eutectic. Ampoule failure is indicated by a step change in resistance of the failure sensor on the order of megohms. The sensors will increase the safety of crystal growth experiments by providing an indication that an ampoule has failed. Experimental results indicate that the response times (after a known ampoule failure) for the 0.003 and 0.010 inch ampoule failure sensors are 2.4 and 3.6 minutes, respectively. This ampoule failure sensor will be utilized in the CGF during the second United States Microgravity Laboratory Mission (USML-2) and is the subject of a NASA patent application.

Cross-Validation of the Computerized Adaptive Screening Test (CAST).

ERIC Educational Resources Information Center

Pliske, Rebecca M.; And Others

The Computerized Adaptive Screening Test (CAST) was developed to provide an estimate at recruiting stations of prospects' Armed Forces Qualification Test (AFQT) scores. The CAST was designed to replace the paper-and-pencil Enlistment Screening Test (EST). The initial validation study of CAST indicated that CAST predicts AFQT at least as accurately…

The validity of upper-limb neurodynamic tests for detecting peripheral neuropathic pain.

PubMed

Nee, Robert J; Jull, Gwendolen A; Vicenzino, Bill; Coppieters, Michel W

2012-05-01

The validity of upper-limb neurodynamic tests (ULNTs) for detecting peripheral neuropathic pain (PNP) was assessed by reviewing the evidence on plausibility, the definition of a positive test, reliability, and concurrent validity. Evidence was identified by a structured search for peer-reviewed articles published in English before May 2011. The quality of concurrent validity studies was assessed with the Quality Assessment of Diagnostic Accuracy Studies tool, where appropriate. Biomechanical and experimental pain data support the plausibility of ULNTs. Evidence suggests that a positive ULNT should at least partially reproduce the patient's symptoms and that structural differentiation should change these symptoms. Data indicate that this definition of a positive ULNT is reliable when used clinically. Limited evidence suggests that the median nerve test, but not the radial nerve test, helps determine whether a patient has cervical radiculopathy. The median nerve test does not help diagnose carpal tunnel syndrome. These findings should be interpreted cautiously, because diagnostic accuracy might have been distorted by the investigators' definitions of a positive ULNT. Furthermore, patients with PNP who presented with increased nerve mechanosensitivity rather than conduction loss might have been incorrectly classified by electrophysiological reference standards as not having PNP. The only evidence for concurrent validity of the ulnar nerve test was a case study on cubital tunnel syndrome. We recommend that researchers develop more comprehensive reference standards for PNP to accurately assess the concurrent validity of ULNTs and continue investigating the predictive validity of ULNTs for prognosis or treatment response.

Out-of-plane buckling of pantographic fabrics in displacement-controlled shear tests: experimental results and model validation

NASA Astrophysics Data System (ADS)

Barchiesi, Emilio; Ganzosch, Gregor; Liebold, Christian; Placidi, Luca; Grygoruk, Roman; Müller, Wolfgang H.

2018-01-01

Due to the latest advancements in 3D printing technology and rapid prototyping techniques, the production of materials with complex geometries has become more affordable than ever. Pantographic structures, because of their attractive features, both in dynamics and statics and both in elastic and inelastic deformation regimes, deserve to be thoroughly investigated with experimental and theoretical tools. Herein, experimental results relative to displacement-controlled large deformation shear loading tests of pantographic structures are reported. In particular, five differently sized samples are analyzed up to first rupture. Results show that the deformation behavior is strongly nonlinear, and the structures are capable of undergoing large elastic deformations without reaching complete failure. Finally, a cutting edge model is validated by means of these experimental results.

Translation, Cultural Adaptation and Validation of the Simple Shoulder Test to Spanish

PubMed Central

Arcuri, Francisco; Barclay, Fernando; Nacul, Ivan

2015-01-01

Background: The validation of widely used scales facilitates the comparison across international patient samples. Objective: The objective was to translate, culturally adapt and validate the Simple Shoulder Test into Argentinian Spanish. Methods: The Simple Shoulder Test was translated from English into Argentinian Spanish by two independent translators, translated back into English and evaluated for accuracy by an expert committee to correct the possible discrepancies. It was then administered to 50 patients with different shoulder conditions.Psycometric properties were analyzed including internal consistency, measured with Cronbach´s Alpha, test-retest reliability at 15 days with the interclass correlation coefficient. Results: The internal consistency, validation, was an Alpha of 0,808, evaluated as good. The test-retest reliability index as measured by intra-class correlation coefficient (ICC) was 0.835, evaluated as excellent. Conclusion: The Simple Shoulder Test translation and it´s cultural adaptation to Argentinian-Spanish demonstrated adequate internal reliability and validity, ultimately allowing for its use in the comparison with international patient samples.

Physical performance tests after stroke: reliability and validity.

PubMed

Maeda, A; Yuasa, T; Nakamura, K; Higuchi, S; Motohashi, Y

2000-01-01

To evaluate the reliability and validity of the modified physical performance tests for stroke survivors who live in a community. The subjects included 40 stroke survivors and 40 apparently healthy independent elderly persons. The physical performance tests for the stroke survivors comprised two physical capacity evaluation tasks that represented physical abilities necessary to perform the main activities of daily living, e.g., standing-up ability (time needed to stand up from bed rest) and walking ability (time needed to walk 10 m). Regarding the reliability of tests, significant correlations were confirmed between test and retest of physical performance tests with both short and long intervals in individuals after stroke. Regarding the validity of tests, the authors studied the significant correlations between the maximum isometric strength of the quardriceps muscle and the time needed to walk 10 m, centimeters reached while sitting and reaching, and the time needed to stand up from bed rest. The authors confirmed that there were significant correlations between the instrumental activity of daily living and the time needed to stand up from bed rest, along with the time needed to walk 10 m for the stroke survivors. These physical performance tests are useful guides for evaluating a level of activity of daily living and physical frailty of stroke survivors living in a community.

Validation of the Narrowing Beam Walking Test in Lower Limb Prosthesis Users.

PubMed

Sawers, Andrew; Hafner, Brian

2018-04-11

To evaluate the content, construct, and discriminant validity of the Narrowing Beam Walking Test (NBWT), a performance-based balance test for lower limb prosthesis users. Cross-sectional study. Research laboratory and prosthetics clinic. Unilateral transtibial and transfemoral prosthesis users (N=40). Not applicable. Content validity was examined by quantifying the percentage of participants receiving maximum or minimum scores (ie, ceiling and floor effects). Convergent construct validity was examined using correlations between participants' NBWT scores and scores or times on existing clinical balance tests regularly administered to lower limb prosthesis users. Known-groups construct validity was examined by comparing NBWT scores between groups of participants with different fall histories, amputation levels, amputation etiologies, and functional levels. Discriminant validity was evaluated by analyzing the area under each test's receiver operating characteristic (ROC) curve. No minimum or maximum scores were recorded on the NBWT. NBWT scores demonstrated strong correlations (ρ=.70‒.85) with scores/times on performance-based balance tests (timed Up and Go test, Four Square Step Test, and Berg Balance Scale) and a moderate correlation (ρ=.49) with the self-report Activities-specific Balance Confidence scale. NBWT performance was significantly lower among participants with a history of falls (P=.003), transfemoral amputation (P=.011), and a lower mobility level (P<.001). The NBWT also had the largest area under the ROC curve (.81) and was the only test to exhibit an area that was statistically significantly >.50 (ie, chance). The results provide strong evidence of content, construct, and discriminant validity for the NBWT as a performance-based test of balance ability. The evidence supports its use to assess balance impairments and fall risk in unilateral transtibial and transfemoral prosthesis users. Copyright © 2018 American Congress of Rehabilitation Medicine

Validation of a clinical critical thinking skills test in nursing

PubMed Central

2015-01-01

Purpose: The purpose of this study was to develop a revised version of the clinical critical thinking skills test (CCTS) and to subsequently validate its performance. Methods: This study is a secondary analysis of the CCTS. Data were obtained from a convenience sample of 284 college students in June 2011. Thirty items were analyzed using item response theory and test reliability was assessed. Test-retest reliability was measured using the results of 20 nursing college and graduate school students in July 2013. The content validity of the revised items was analyzed by calculating the degree of agreement between instrument developer intention in item development and the judgments of six experts. To analyze response process validity, qualitative data related to the response processes of nine nursing college students obtained through cognitive interviews were analyzed. Results: Out of initial 30 items, 11 items were excluded after the analysis of difficulty and discrimination parameter. When the 19 items of the revised version of the CCTS were analyzed, levels of item difficulty were found to be relatively low and levels of discrimination were found to be appropriate or high. The degree of agreement between item developer intention and expert judgments equaled or exceeded 50%. Conclusion: From above results, evidence of the response process validity was demonstrated, indicating that subjects respondeds as intended by the test developer. The revised 19-item CCTS was found to have sufficient reliability and validity and will therefore represents a more convenient measurement of critical thinking ability. PMID:25622716

Validation of Alternative In Vitro Methods to Animal Testing: Concepts, Challenges, Processes and Tools.

PubMed

Griesinger, Claudius; Desprez, Bertrand; Coecke, Sandra; Casey, Warren; Zuang, Valérie

This chapter explores the concepts, processes, tools and challenges relating to the validation of alternative methods for toxicity and safety testing. In general terms, validation is the process of assessing the appropriateness and usefulness of a tool for its intended purpose. Validation is routinely used in various contexts in science, technology, the manufacturing and services sectors. It serves to assess the fitness-for-purpose of devices, systems, software up to entire methodologies. In the area of toxicity testing, validation plays an indispensable role: "alternative approaches" are increasingly replacing animal models as predictive tools and it needs to be demonstrated that these novel methods are fit for purpose. Alternative approaches include in vitro test methods, non-testing approaches such as predictive computer models up to entire testing and assessment strategies composed of method suites, data sources and decision-aiding tools. Data generated with alternative approaches are ultimately used for decision-making on public health and the protection of the environment. It is therefore essential that the underlying methods and methodologies are thoroughly characterised, assessed and transparently documented through validation studies involving impartial actors. Importantly, validation serves as a filter to ensure that only test methods able to produce data that help to address legislative requirements (e.g. EU's REACH legislation) are accepted as official testing tools and, owing to the globalisation of markets, recognised on international level (e.g. through inclusion in OECD test guidelines). Since validation creates a credible and transparent evidence base on test methods, it provides a quality stamp, supporting companies developing and marketing alternative methods and creating considerable business opportunities. Validation of alternative methods is conducted through scientific studies assessing two key hypotheses, reliability and relevance of the

Implementation and Initial Validation of the APS English Test [and] The APS English-Writing Test at Golden West College: Evidence for Predictive Validity.

ERIC Educational Resources Information Center

Isonio, Steven

In May 1991, Golden West College (California) conducted a validation study of the English portion of the Assessment and Placement Services for Community Colleges (APS), followed by a predictive validity study in July 1991. The initial study was designed to aid in the implementation of the new test at GWC by comparing data on APS use at other…

Construct Validity of Physical Fitness Tests

DTIC Science & Technology

2011-02-03

Medicine and Science in Sports and Exercise , 21, 319-324. *Fleishman, E. A. (1964). The structure and measurement of physical fitness. Englewood Cliffs...Quarterly for Exercise and Sport, 64, 256-273. *McCloy, E. (1935). Factor analysis methods in the measurement of physical abilities. Research Quarterly...Research Quarterly, 34, 525. Physical Fitness Test Validity 23 Powers, S. K., & Howley, E. T. (1990). Exercise physiology: Theory and application to

Development of an Agility Test for Badminton Players and Assessment of Its Validity and Test-Retest Reliability.

PubMed

Loureiro, Luiz de França Bahia; de Freitas, Paulo Barbosa

2016-04-01

Badminton requires open and fast actions toward the shuttlecock, but there is no specific agility test for badminton players with specific movements. To develop an agility test that simultaneously assesses perception and motor capacity and examine the test's concurrent and construct validity and its test-retest reliability. The Badcamp agility test consists of running as fast as possible to 6 targets placed on the corners and middle points of a rectangular area (5.6 × 4.2 m) from the start position located in the center of it, following visual stimuli presented in a luminous panel. The authors recruited 43 badminton players (17-32 y old) to evaluate concurrent (with shuttle-run agility test--SRAT) and construct validity and test-retest reliability. Results revealed that Badcamp presents concurrent and construct validity, as its performance is strongly related to SRAT (ρ = 0.83, P < .001), with performance of experts being better than nonexpert players (P < .01). In addition, Badcamp is reliable, as no difference (P = .07) and a high intraclass correlation (ICC = .93) were found in the performance of the players on 2 different occasions. The findings indicate that Badcamp is an effective, valid, and reliable tool to measure agility, allowing coaches and athletic trainers to evaluate players' athletic condition and training effectiveness and possibly detect talented individuals in this sport.

Testing and failure analysis to improve screening techniques for hermetically sealed metallized film capacitors for low energy applications

NASA Technical Reports Server (NTRS)

1982-01-01

Effective screening techniques are evaluated for detecting insulation resistance degradation and failure in hermetically sealed metallized film capacitors used in applications where low capacitor voltage and energy levels are common to the circuitry. A special test and monitoring system capable of rapidly scanning all test capacitors and recording faults and/or failures is examined. Tests include temperature cycling and storage as well as low, medium, and high voltage life tests. Polysulfone film capacitors are more heat stable and reliable than polycarbonate film units.

Development and validation of a knowledge test for health professionals regarding lifestyle modification.

PubMed

Talip, Whadi-ah; Steyn, Nelia P; Visser, Marianne; Charlton, Karen E; Temple, Norman

2003-09-01

We wanted to develop and validate a test that assesses the knowledge and practices of health professionals (HPs) with regard to the role of nutrition, physical activity, and smoking cessation (lifestyle modification) in chronic diseases of lifestyle. A descriptive cross-sectional validation study was carried out. The validation design consisted of two phases, namely 1) test planning and development and 2) test evaluation. The study sample consisted of five groups of HPs: dietitians, dietetic interns, general practitioners, medical students, and nurses. The overall response rate was 58%, resulting in a sample size of 186 participants. A test was designed to evaluate the knowledge and practices of HPs. The test was first evaluated by an expert group to ensure content, construct, and face validity. Thereafter, the questionnaire was tested on five groups of HPs to test for criterion validity. Internal consistency was evaluated by Cronbach's alpha. An expert panel ensured content, construct, and face validity of the test. Groups with the most training and exposure to nutrition (dietitians and dietetic interns) had the highest group mean score, ranging from 61% to 88%, whereas those with limited nutrition training (general practitioners, medical students, and nurses) had significantly lower scores, ranging from 26% to 80%. This result demonstrated criterion validity. Internal consistency of the overall test demonstrated a Cronbach's alpha of 0.99. Most HPs identified the mass media as their main source of information on lifestyle modification. These HPs also identified lack of time, lack of patient compliance, and lack of knowledge as barriers that prevent them from providing counseling on lifestyle modification. The results of this study showed that this test instrument identifies groups of health professionals with adequate training (knowledge) in lifestyle modification and those who require further training (knowledge).

Validation of prognostic scores to predict short-term mortality in patients with acute-on-chronic liver failure.

PubMed

Song, Do Seon; Kim, Tae Yeob; Kim, Dong Joon; Kim, Hee Yeon; Sinn, Dong Hyun; Yoon, Eileen L; Kim, Chang Wook; Jung, Young Kul; Suk, Ki Tae; Lee, Sang Soo; Lee, Chang Hyeong; Kim, Tae Hun; Choe, Won Hyeok; Yim, Hyung Joon; Kim, Sung Eun; Baik, Soon Koo; Jang, Jae Young; Kim, Hyoung Su; Kim, Sang Gyune; Yang, Jin Mo; Sohn, Joo Hyun; Choi, Eun Hee; Cho, Hyun Chin; Jeong, Soung Won; Kim, Moon Young

2018-04-01

The aim of this study was to validate the chronic liver failure-sequential organ failure assessment score (CLIF-SOFAs), CLIF consortium organ failure score (CLIF-C OFs), CLIF-C acute-on-chronic liver failure score (CLIF-C ACLFs), and CLIF-C acute decompensation score in Korean chronic liver disease patients with acute deterioration. Acute-on-chronic liver failure was defined by either the Asian Pacific Association for the study of the Liver ACLF Research Consortium (AARC) or CLIF-C criteria. The diagnostic performances for short-term mortality were compared by the area under the receiver operating characteristic curve. Among a total of 1470 patients, 252 patients were diagnosed with ACLF according to the CLIF-C (197 patients) or AARC definition (95 patients). As the ACLF grades increased, the survival rates became significantly lower. The areas under the receiver operating characteristic of the CLIF-SOFAs, CLIF-C OFs, and CLIF-C ACLFs were significantly higher than those of the Child-Pugh, model for end-stage liver disease, and model for end-stage liver disease-Na scores in ACLF patients according to the CLIF-C definition (all P < 0.05), but there were no significant differences in patients without ACLF or in patients with ACLF according to the AARC definition. The CLIF-SOFAs, CLIF-C OFs, and CLIF-C ACLFs had higher specificities with a fixed sensitivity than liver specific scores in ACLF patients according to the CLIF-C definition, but not in ACLF patients according to the AARC definition. The CLIF-SOFAs, CLIF-C OFs, and CLIF-C ACLFs are useful scoring systems that provide accurate information on prognosis in patients with ACLF according to the CLIF-C definition, but not the AARC definition. © 2017 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Health information systems: failure, success and improvisation.

PubMed

Heeks, Richard

2006-02-01

The generalised assumption of health information systems (HIS) success is questioned by a few commentators in the medical informatics field. They point to widespread HIS failure. The purpose of this paper was therefore to develop a better conceptual foundation for, and practical guidance on, health information systems failure (and success). Literature and case analysis plus pilot testing of developed model. Defining HIS failure and success is complex, and the current evidence base on HIS success and failure rates was found to be weak. Nonetheless, the best current estimate is that HIS failure is an important problem. The paper therefore derives and explains the "design-reality gap" conceptual model. This is shown to be robust in explaining multiple cases of HIS success and failure, yet provides a contingency that encompasses the differences which exist in different HIS contexts. The design-reality gap model is piloted to demonstrate its value as a tool for risk assessment and mitigation on HIS projects. It also throws into question traditional, structured development methodologies, highlighting the importance of emergent change and improvisation in HIS. The design-reality gap model can be used to address the problem of HIS failure, both as a post hoc evaluative tool and as a pre hoc risk assessment and mitigation tool. It also validates a set of methods, techniques, roles and competencies needed to support the dynamic improvisations that are found to underpin cases of HIS success.

49 CFR 40.89 - What is validity testing, and are laboratories required to conduct it?

Code of Federal Regulations, 2013 CFR

2013-10-01

... PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.89 What is validity testing, and are laboratories required to conduct it? (a) Specimen validity testing is... 49 Transportation 1 2013-10-01 2013-10-01 false What is validity testing, and are laboratories...

49 CFR 40.89 - What is validity testing, and are laboratories required to conduct it?

Code of Federal Regulations, 2011 CFR

2011-10-01

... PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.89 What is validity testing, and are laboratories required to conduct it? (a) Specimen validity testing is... 49 Transportation 1 2011-10-01 2011-10-01 false What is validity testing, and are laboratories...

49 CFR 40.89 - What is validity testing, and are laboratories required to conduct it?

Code of Federal Regulations, 2010 CFR

2010-10-01

... PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.89 What is validity testing, and are laboratories required to conduct it? (a) Specimen validity testing is... 49 Transportation 1 2010-10-01 2010-10-01 false What is validity testing, and are laboratories...

49 CFR 40.89 - What is validity testing, and are laboratories required to conduct it?

Code of Federal Regulations, 2012 CFR

2012-10-01

... PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.89 What is validity testing, and are laboratories required to conduct it? (a) Specimen validity testing is... 49 Transportation 1 2012-10-01 2012-10-01 false What is validity testing, and are laboratories...

49 CFR 40.89 - What is validity testing, and are laboratories required to conduct it?

Code of Federal Regulations, 2014 CFR

2014-10-01

... PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.89 What is validity testing, and are laboratories required to conduct it? (a) Specimen validity testing is... 49 Transportation 1 2014-10-01 2014-10-01 false What is validity testing, and are laboratories...

An accelerating precursor to predict "time-to-failure" in creep and volcanic eruptions

NASA Astrophysics Data System (ADS)

Hao, Shengwang; Yang, Hang; Elsworth, Derek

2017-09-01

Real-time prediction by monitoring of the evolution of response variables is a central goal in predicting rock failure. A linear relation Ω˙Ω¨-1 = C(tf - t) has been developed to describe the time to failure, where Ω represents a response quantity, C is a constant and tf represents the failure time. Observations from laboratory creep failure experiments and precursors to volcanic eruptions are used to test the validity of the approach. Both cumulative and simple moving window techniques are developed to perform predictions and to illustrate the effects of data selection on the results. Laboratory creep failure experiments on granites show that the linear relation works well during the final approach to failure. For blind prediction, the simple moving window technique is preferred because it always uses the most recent data and excludes effects of early data deviating significantly from the predicted trend. When the predicted results show only small fluctuations, failure is imminent.

The Unified Language Testing Plan: Speaking Proficiency Test. Russian Pilot Validation Studies. Report Number 2.

ERIC Educational Resources Information Center

Thornton, Julie A.

The report describes one segment of the Federal Language Testing Board's Unified Language Testing Plan (ULTP), the validation of the speaking proficiency test in Russian. The ULTP is a project to increase standardization of foreign language proficiency measurement and promote sharing of resources among testing programs in the federal government.…

Validation of the Arabic Version of the Internet Gaming Disorder-20 Test.

PubMed

Hawi, Nazir S; Samaha, Maya

2017-04-01

In recent years, researchers have been trying to shed light on gaming addiction and its association with different psychiatric disorders and psychological determinants. The latest edition version of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) included in its Section 3 Internet Gaming Disorder (IGD) as a condition for further empirical study and proposed nine criteria for the diagnosis of IGD. The 20-item Internet Gaming Disorder (IGD-20) Test was developed as a valid and reliable tool to assess gaming addiction based on the nine criteria set by the DSM-5. The aim of this study is to validate an Arabic version of the IGD-20 Test. The Arabic version of IGD-20 will not only help in identifying Arabic-speaking pathological gamers but also stimulate cross-cultural studies that could contribute to an area in need of more research for insight and treatment. After a process of translation and back-translation and with the participation of a sizable sample of Arabic-speaking adolescents, the present study conducted a psychometric validation of the IGD-20 Test. Our confirmatory factor analysis showed the validity of the Arabic version of the IGD-20 Test. The one-factor model of the Arabic IGD-20 Test had very good psychometric properties, and it fitted the sample data extremely well. In addition, correlation analysis between the IGD-20 Test and the daily duration on weekdays and weekends gameplay revealed significant positive relationships that warranted a criterion-related validation. Thus, the Arabic version of the IGD-20 Test is a valid and reliable measure of IGD among Arabic-speaking populations.

A Human Proximity Operations System test case validation approach

NASA Astrophysics Data System (ADS)

Huber, Justin; Straub, Jeremy

A Human Proximity Operations System (HPOS) poses numerous risks in a real world environment. These risks range from mundane tasks such as avoiding walls and fixed obstacles to the critical need to keep people and processes safe in the context of the HPOS's situation-specific decision making. Validating the performance of an HPOS, which must operate in a real-world environment, is an ill posed problem due to the complexity that is introduced by erratic (non-computer) actors. In order to prove the HPOS's usefulness, test cases must be generated to simulate possible actions of these actors, so the HPOS can be shown to be able perform safely in environments where it will be operated. The HPOS must demonstrate its ability to be as safe as a human, across a wide range of foreseeable circumstances. This paper evaluates the use of test cases to validate HPOS performance and utility. It considers an HPOS's safe performance in the context of a common human activity, moving through a crowded corridor, and extrapolates (based on this) to the suitability of using test cases for AI validation in other areas of prospective application.

Reproducibility of the Self-Controlled Six-Minute Walking Test in Heart Failure Patients

PubMed Central

Guimarães, Guilherme Veiga; Carvalho, Vitor Oliveira; Bocchi, Edimar Alcides

2008-01-01

INTRODUCTION The six-minute walk test (6WT) has been proposed to be a submaximal test, but could actually demand a high level of exercise intensity from the patient, expressed by a respiratory quotient >1.0, following the guideline recommendations. Standardizing the 6WT using the Borg scale was proposed to make sure that all patients undergo a submaximal walking test. PURPOSE To test the reproducibility of the six-minute treadmill cardiopulmonary walk test (6CWT) using the Borg scale and to make sure that all patients undergo a submaximal test. METHODS Twenty-three male heart failure patients (50±9 years) were included; these patients had both ischemic (5) and non-ischemic (18) heart failure with a left ventricle ejection fraction of 23±7%, were diagnosed as functional class NYHA II-III and were undergoing optimized drug therapy. Patients were guided to walk at a pace between “relatively easy and slightly tiring” (11 and 13 on Borg scale). The 6CWT using the Borg scale was performed two times on a treadmill with zero inclination and patient control of speed with an interval of 24 hours. During the sixth minute, we analyzed ventilation (VE, L/min), respiratory quotient, Oxygen consumption (VO2, ml/kg/min), VE/VCO2 slope, heart rate (HR, bpm), systolic blood pressure (SBP, mmHg), diastolic (DBP, mmHg) blood pressure and distance. RESULTS The intraclass correlation coefficients at the sixth minute were: HR (ri=0.96, p<0.0001), VE (ri=0.84, p<0.0001), SBP (ri=0.72, p=0.001), distance (ri=0.88, p<0.0001), VO2 (ri=0.92, p<0.0001), SlopeVE/VCO2 (ri=0.86, p<0.0001) and RQ<1 (ri=0.6, p=0.004). CONCLUSION Using the 6CWT with the Borg scale was reproducible, and it seems to be an appropriate method to evaluate the functional capacity of heart failure patients while making sure that they undergo a submaximal walking test. PMID:18438574

Reproducibility of the self-controlled six-minute walking test in heart failure patients.

PubMed

Guimarães, Guilherme Veiga; Carvalho, Vitor Oliveira; Bocchi, Edimar Alcides

2008-04-01

The six-minute walk test (6WT) has been proposed to be a submaximal test, but could actually demand a high level of exercise intensity from the patient, expressed by a respiratory quotient >1.0, following the guideline recommendations. Standardizing the 6WT using the Borg scale was proposed to make sure that all patients undergo a submaximal walking test. To test the reproducibility of the six-minute treadmill cardiopulmonary walk test (6CWT) using the Borg scale and to make sure that all patients undergo a submaximal test. Twenty-three male heart failure patients (50+/-9 years) were included; these patients had both ischemic (5) and non-ischemic (18) heart failure with a left ventricle ejection fraction of 23+/-7%, were diagnosed as functional class NYHA II-III and were undergoing optimized drug therapy. Patients were guided to walk at a pace between "relatively easy and slightly tiring" (11 and 13 on Borg scale). The 6CWT using the Borg scale was performed two times on a treadmill with zero inclination and patient control of speed with an interval of 24 hours. During the sixth minute, we analyzed ventilation (VE, L/min), respiratory quotient, Oxygen consumption (VO2, ml/kg/min), VE/VCO2 slope, heart rate (HR, bpm), systolic blood pressure (SBP, mmHg), diastolic (DBP, mmHg) blood pressure and distance. The intraclass correlation coefficients at the sixth minute were: HR (r i=0.96, p<0.0001), VE (r i=0.84, p<0.0001), SBP (r i=0.72, p=0.001), distance (r i=0.88, p<0.0001), VO2 (r i=0.92, p<0.0001), SlopeVE/VCO2 (r i=0.86, p<0.0001) and RQ<1 (r i=0.6, p=0.004). Using the 6CWT with the Borg scale was reproducible, and it seems to be an appropriate method to evaluate the functional capacity of heart failure patients while making sure that they undergo a submaximal walking test.

Validity and Reliability Testing of an e-learning Questionnaire for Chemistry Instruction

NASA Astrophysics Data System (ADS)

Guspatni, G.; Kurniawati, Y.

2018-04-01

The aim of this paper is to examine validity and reliability of a questionnaire used to evaluate e-learning implementation in chemistry instruction. 48 questionnaires were filled in by students who had studied chemistry through e-learning system. The questionnaire consisted of 20 indicators evaluating students’ perception on using e-learning. Parametric testing was done as data were assumed to follow normal distribution. Item validity of the questionnaire was examined through item-total correlation using Pearson’s formula while its reliability was assessed with Cronbach’s alpha formula. Moreover, convergent validity was assessed to see whether indicators building a factor had theoretically the same underlying construct. The result of validity testing revealed 19 valid indicators while the result of reliability testing revealed Cronbach’s alpha value of .886. The result of factor analysis showed that questionnaire consisted of five factors, and each of them had indicators building the same construct. This article shows the importance of factor analysis to get a construct valid questionnaire before it is used as research instrument.

Establishing the Test-Retest Reliability & Concurrent Validity for the Repeat Ice Skating Test (RIST) in Adolescent Male Ice Hockey Players

ERIC Educational Resources Information Center

Power, Allan; Faught, Brent E.; Przysucha, Eryk; McPherson, Moira; Montelpare, William

2012-01-01

In this study the authors examine the test-retest reliability and concurrent validity of the Repeat Ice Skating Test (RIST). This was an on-ice field anaerobic test that measured average peak power and was validated with 3 anaerobic lab tests: (a) vertical jump, (b) the Margaria-Kalamen stair test, and (c) the Wingate Anaerobic Test. The…

Construct validity of the Health Science Reasoning Test.

PubMed

Huhn, Karen; Black, Lisa; Jensen, Gail M; Deutsch, Judith E

2011-01-01

The aim of this study was to evaluate the construct validity of the Health Science Reasoning Test (HSRT) by determining if the test could discriminate between expert and novice physical therapists' critical-thinking skills. Experts identified from a random list of certified clinical specialists and students in the first year of their physical therapy education from two physical therapy programs completed the HSRT. Experts (n = 73) had a higher total HSRT score (mean 24.06, SD 3.92) than the novices (n = 79) (mean 22.49, SD 3.2), with the difference being statistically significant t (148) = 2.67, p = 0.008. The HSRT total score discriminated between expert and novice critical-thinking skills, therefore establishing construct validity. To our knowledge, this is the first study to compare expert and novice performance on a standardized test. The opportunity to have a tool that provides evidence of students' critical thinking skills could be helpful for educators and students. The test results could aid in identifying areas of students' strengths and weaknesses, thereby enabling targeted remediation to improve critical thinking skills, which are key factors in clinical reasoning, a necessary skill for effective physical therapy practice.

Validity of an Interactive Functional Reach Test.

PubMed

Galen, Sujay S; Pardo, Vicky; Wyatt, Douglas; Diamond, Andrew; Brodith, Victor; Pavlov, Alex

2015-08-01

Videogaming platforms such as the Microsoft (Redmond, WA) Kinect(®) are increasingly being used in rehabilitation to improve balance performance and mobility. These gaming platforms do not have built-in clinical measures that offer clinically meaningful data. We have now developed software that will enable the Kinect sensor to assess a patient's balance using an interactive functional reach test (I-FRT). The aim of the study was to test the concurrent validity of the I-FRT and to establish the feasibility of implementing the I-FRT in a clinical setting. The concurrent validity of the I-FRT was tested among 20 healthy adults (mean age, 25.8±3.4 years; 14 women). The Functional Reach Test (FRT) was measured simultaneously by both the Kinect sensor using the I-FRT software and the Optotrak Certus(®) 3D motion-capture system (Northern Digital Inc., Waterloo, ON, Canada). The feasibility of implementing the I-FRT in a clinical setting was assessed by performing the I-FRT in 10 participants with mild balance impairments recruited from the outpatient physical therapy clinic (mean age, 55.8±13.5 years; four women) and obtaining their feedback using a NASA Task Load Index (NASA-TLX) questionnaire. There was moderate to good agreement between FRT measures made by the two measurement systems. The greatest agreement between the two measurement system was found with the Kinect sensor placed at a distance of 2.5 m [intraclass correlation coefficient (2,k)=0.786; P<0.001] from the participant. Participants with mild balance impairments whose balance was assessed using the I-FRT software scored their experience favorably by assigning lower scores for the Frustration, Mental Demand, and Temporal Demand subscales on the NASA/TLX questionnaire. FRT measures made using the Kinect sensor I-FRT software provides a valid clinical measure that can be used with the gaming platforms.

Beyond Faith and Face Validity: The Multitrait-Multimethod Matrix and the Convergent and Discriminant Validity of Oral Proficiency Tests.

ERIC Educational Resources Information Center

Stevenson, Douglas K.

Recently there has been a renewed international interest in direct oral proficiency measures such as the oral interview. There has also been a growing awareness among some language testing specialists that all proficiency tests must be subjected to construct validation. It seems that the high face validity of oral interviews tends to cloud and…

Spontaneous breathing test in the prediction of extubation failure in the pediatric population.

PubMed

Nascimento, Milena Siciliano; Rebello, Celso Moura; Vale, Luciana Assis Pires Andrade; Santos, Érica; Prado, Cristiane do

2017-01-01

To assess whether the spontaneous breathing test can predict the extubation failure in pediatric population. A prospective and observational study that evaluated data of inpatients at the Pediatric Intensive Care Unit between May 2011 and August 2013, receiving mechanical ventilation for at least 24 hours followed by extubation. The patients were classified in two groups: Test Group, with patients extubated after spontaneous breathing test, and Control Group, with patients extubated without spontaneous breathing test. A total of 95 children were enrolled in the study, 71 in the Test Group and 24 in the Control Group. A direct comparison was made between the two groups regarding sex, age, mechanical ventilation time, indication to start mechanical ventilation and respiratory parameters before extubation in the Control Group, and before the spontaneous breathing test in the Test Group. There was no difference between the parameters evaluated. According to the analysis of probability of extubation failure between the two groups, the likelihood of extubation failure in the Control Group was 1,412 higher than in the Test Group, nevertheless, this range did not reach significance (p=0.706). This model was considered well-adjusted according to the Hosmer-Lemeshow test (p=0.758). The spontaneous breathing test was not able to predict the extubation failure in pediatric population. Avaliar se o teste de respiração espontânea pode ser utilizado para predizer falha da extubação na população pediátrica. Estudo prospectivo, observacional, no qual foram avaliados todos os pacientes internados no Centro de Terapia Intensiva Pediátrica, no período de maio de 2011 a agosto de 2013, que utilizaram ventilação mecânica por mais de 24 horas e que foram extubados. Os pacientes foram classificados em dois grupos: Grupo Teste, que incluiu os pacientes extubados depois do teste de respiração espontânea; e Grupo Controle, pacientes foram sem teste de respiração espont

Reliability and validity of the revised Gibson Test of Cognitive Skills, a computer-based test battery for assessing cognition across the lifespan.

PubMed

Moore, Amy Lawson; Miller, Terissa M

2018-01-01

The purpose of the current study is to evaluate the validity and reliability of the revised Gibson Test of Cognitive Skills, a computer-based battery of tests measuring short-term memory, long-term memory, processing speed, logic and reasoning, visual processing, as well as auditory processing and word attack skills. This study included 2,737 participants aged 5-85 years. A series of studies was conducted to examine the validity and reliability using the test performance of the entire norming group and several subgroups. The evaluation of the technical properties of the test battery included content validation by subject matter experts, item analysis and coefficient alpha, test-retest reliability, split-half reliability, and analysis of concurrent validity with the Woodcock Johnson III Tests of Cognitive Abilities and Tests of Achievement. Results indicated strong sources of evidence of validity and reliability for the test, including internal consistency reliability coefficients ranging from 0.87 to 0.98, test-retest reliability coefficients ranging from 0.69 to 0.91, split-half reliability coefficients ranging from 0.87 to 0.91, and concurrent validity coefficients ranging from 0.53 to 0.93. The Gibson Test of Cognitive Skills-2 is a reliable and valid tool for assessing cognition in the general population across the lifespan.

Reliability and validity of an audio signal modified shuttle walk test.

PubMed

Singla, Rupak; Rai, Richa; Faye, Abhishek Anil; Jain, Anil Kumar; Chowdhury, Ranadip; Bandyopadhyay, Debdutta

2017-01-01

The audio signal in the conventionally accepted protocol of shuttle walk test (SWT) is not well-understood by the patients and modification of the audio signal may improve the performance of the test. The aim of this study is to study the validity and reliability of an audio signal modified SWT, called the Singla-Richa modified SWT (SWTSR), in healthy normal adults. In SWTSR, the audio signal was modified with the addition of reverse counting to it. A total of 54 healthy normal adults underwent conventional SWT (CSWT) at one instance and two times SWTSRon the same day. The validity was assessed by comparing outcomes of the SWTSRto outcomes of CSWT using the Pearson correlation coefficient and Bland-Altman plot. Test-retest reliability of SWTSRwas assessed using the intraclass correlation coefficient (ICC). The acceptability of the modified test in comparison to the conventional test was assessed using Likert scale. The distance walked (mean ± standard deviation) in the CSWT and SWTSRtest was 853.33 ± 217.33 m and 857.22 ± 219.56 m, respectively (Pearson correlation coefficient - 0.98; P < 0.001) indicating SWTSRto be a valid test. The SWTSRwas found to be a reliable test with ICC of 0.98 (95% confidence interval: 0.97-0.99). The acceptability of SWTSRwas significantly higher than CSWT. The SWTSRwith modified audio signal with reverse counting is a reliable as well as a valid test when compared with CSWT in healthy normal adults. It better understood by subjects compared to CSWT.

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

Reliability and Validity of the Standing Heel-Rise Test

ERIC Educational Resources Information Center

Yocum, Allison; McCoy, Sarah Westcott; Bjornson, Kristie F.; Mullens, Pamela; Burton, Gay Naganuma

2010-01-01

A standardized protocol for a pediatric heel-rise test was developed and reliability and validity are reported. Fifty-seven children developing typically (CDT) and 34 children with plantar flexion weakness performed three tests: unilateral heel rise, vertical jump, and force measurement using handheld dynamometry. Intraclass correlation…

Cross-Cultural Validation of TEMAS, a Minority Projective Test.

ERIC Educational Resources Information Center

Costantino, Giuseppe; And Others

The theoretical framework and cross-cultural validation of Tell-Me-A-Story (TEMAS), a projective test developed to measure personality development in ethnic minority children, is presented. The TEMAS test consists of 23 chromatic pictures which incorporate the following characteristics: (1) representation of antithetical concepts which the…

Clinical Functional Capacity Testing in Patients With Facioscapulohumeral Muscular Dystrophy: Construct Validity and Interrater Reliability of Antigravity Tests.

PubMed

Rijken, Noortje H; van Engelen, Baziel G; Weerdesteyn, Vivian; Geurts, Alexander C

2015-12-01

To evaluate the construct validity and interrater reliability of 4 simple antigravity tests in a small group of patients with facioscapulohumeral muscular dystrophy (FSHD). Case-control study. University medical center. Patients with various severity levels of FSHD (n=9) and healthy control subjects (n=10) were included (N=19). Not applicable. A 4-point ordinal scale was designed to grade performance on the following 4 antigravity tests: sit to stance, stance to sit, step up, and step down. In addition, the 6-minute walk test, 10-m walking test, Berg Balance Scale, and timed Up and Go test were administered as conventional tests. Construct validity was determined by linear regression analysis using the Clinical Severity Score (CSS) as the dependent variable. Interrater agreement was tested using a κ analysis. Patients with FSHD performed worse on all 4 antigravity tests compared with the controls. Stronger correlations were found within than between test categories (antigravity vs conventional). The antigravity tests revealed the highest explained variance with regard to the CSS (R(2)=.86, P=.014). Interrater agreement was generally good. The results of this exploratory study support the construct validity and interrater reliability of the proposed antigravity tests for the assessment of functional capacity in patients with FSHD taking into account the use of compensatory strategies. Future research should further validate these results in a larger sample of patients with FSHD. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Validation of Milliflex® Quantum for Bioburden Testing of Pharmaceutical Products.

PubMed

Gordon, Oliver; Goverde, Marcel; Staerk, Alexandra; Roesti, David

2017-01-01

This article reports the validation strategy used to demonstrate that the Milliflex ® Quantum yielded non-inferior results to the traditional bioburden method. It was validated according to USP <1223>, European Pharmacopoeia 5.1.6, and Parenteral Drug Association Technical Report No. 33 and comprised the validation parameters robustness, ruggedness, repeatability, specificity, limit of detection and quantification, accuracy, precision, linearity, range, and equivalence in routine operation. For the validation, a combination of pharmacopeial ATCC strains as well as a broad selection of in-house isolates were used. In-house isolates were used in stressed state. Results were statistically evaluated regarding the pharmacopeial acceptance criterion of ≥70% recovery compared to the traditional method. Post-hoc test power calculations verified the appropriateness of the used sample size to detect such a difference. Furthermore, equivalence tests verified non-inferiority of the rapid method as compared to the traditional method. In conclusion, the rapid bioburden on basis of the Milliflex ® Quantum was successfully validated as alternative method to the traditional bioburden test. LAY ABSTRACT: Pharmaceutical drug products must fulfill specified quality criteria regarding their microbial content in order to ensure patient safety. Drugs that are delivered into the body via injection, infusion, or implantation must be sterile (i.e., devoid of living microorganisms). Bioburden testing measures the levels of microbes present in the bulk solution of a drug before sterilization, and thus it provides important information for manufacturing a safe product. In general, bioburden testing has to be performed using the methods described in the pharmacopoeias (membrane filtration or plate count). These methods are well established and validated regarding their effectiveness; however, the incubation time required to visually identify microbial colonies is long. Thus, alternative

Non-Nuclear Validation Test Results of a Closed Brayton Cycle Test-Loop

NASA Astrophysics Data System (ADS)

Wright, Steven A.

2007-01-01

Both NASA and DOE have programs that are investigating advanced power conversion cycles for planetary surface power on the moon or Mars, or for next generation nuclear power plants on earth. Although open Brayton cycles are in use for many applications (combined cycle power plants, aircraft engines), only a few closed Brayton cycles have been tested. Experience with closed Brayton cycles coupled to nuclear reactors is even more limited and current projections of Brayton cycle performance are based on analytic models. This report describes and compares experimental results with model predictions from a series of non-nuclear tests using a small scale closed loop Brayton cycle available at Sandia National Laboratories. A substantial amount of testing has been performed, and the information is being used to help validate models. In this report we summarize the results from three kinds of tests. These tests include: 1) test results that are useful for validating the characteristic flow curves of the turbomachinery for various gases ranging from ideal gases (Ar or Ar/He) to non-ideal gases such as CO2, 2) test results that represent shut down transients and decay heat removal capability of Brayton loops after reactor shut down, and 3) tests that map a range of operating power versus shaft speed curve and turbine inlet temperature that are useful for predicting stable operating conditions during both normal and off-normal operating behavior. These tests reveal significant interactions between the reactor and balance of plant. Specifically these results predict limited speed up behavior of the turbomachinery caused by loss of load, the conditions for stable operation, and for direct cooled reactors, the tests reveal that the coast down behavior during loss of power events can extend for hours provided the ultimate heat sink remains available.

PZT Active Frequency Based Wind Blade Fatigue to Failure Testing Results for Various Blade Designs

DTIC Science & Technology

2011-09-01

PZT Active Frequency Based Wind Blade Fatigue to Failure Testing Results for Various Blade Designs R. J. WERLINK...number. 1. REPORT DATE SEP 2011 2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE PZT Active Frequency Based Wind Blade Fatigue ...18 Abstract: This paper summarizes NASA PZT Health Monitoring System results previously reported for 9 meter blade Fatigue loading to failure

A Zebrafish Heart Failure Model for Assessing Therapeutic Agents.

PubMed

Zhu, Xiao-Yu; Wu, Si-Qi; Guo, Sheng-Ya; Yang, Hua; Xia, Bo; Li, Ping; Li, Chun-Qi

2018-03-20

Heart failure is a leading cause of death and the development of effective and safe therapeutic agents for heart failure has been proven challenging. In this study, taking advantage of larval zebrafish, we developed a zebrafish heart failure model for drug screening and efficacy assessment. Zebrafish at 2 dpf (days postfertilization) were treated with verapamil at a concentration of 200 μM for 30 min, which were determined as optimum conditions for model development. Tested drugs were administered into zebrafish either by direct soaking or circulation microinjection. After treatment, zebrafish were randomly selected and subjected to either visual observation and image acquisition or record videos under a Zebralab Blood Flow System. The therapeutic effects of drugs on zebrafish heart failure were quantified by calculating the efficiency of heart dilatation, venous congestion, cardiac output, and blood flow dynamics. All 8 human heart failure therapeutic drugs (LCZ696, digoxin, irbesartan, metoprolol, qiliqiangxin capsule, enalapril, shenmai injection, and hydrochlorothiazide) showed significant preventive and therapeutic effects on zebrafish heart failure (p < 0.05, p < 0.01, and p < 0.001) in the zebrafish model. The larval zebrafish heart failure model developed and validated in this study could be used for in vivo heart failure studies and for rapid screening and efficacy assessment of preventive and therapeutic drugs.

Genomic analysis of bone marrow failure and myelodysplastic syndromes reveals phenotypic and diagnostic complexity

PubMed Central

Zhang, Michael Y.; Keel, Siobán B.; Walsh, Tom; Lee, Ming K.; Gulsuner, Suleyman; Watts, Amanda C.; Pritchard, Colin C.; Salipante, Stephen J.; Jeng, Michael R.; Hofmann, Inga; Williams, David A.; Fleming, Mark D.; Abkowitz, Janis L.; King, Mary-Claire; Shimamura, Akiko

2015-01-01

Accurate and timely diagnosis of inherited bone marrow failure and inherited myelodysplastic syndromes is essential to guide clinical management. Distinguishing inherited from acquired bone marrow failure/myelodysplastic syndrome poses a significant clinical challenge. At present, diagnostic genetic testing for inherited bone marrow failure/myelodysplastic syndrome is performed gene-by-gene, guided by clinical and laboratory evaluation. We hypothesized that standard clinically-directed genetic testing misses patients with cryptic or atypical presentations of inherited bone marrow failure/myelodysplastic syndrome. In order to screen simultaneously for mutations of all classes in bone marrow failure/myelodysplastic syndrome genes, we developed and validated a panel of 85 genes for targeted capture and multiplexed massively parallel sequencing. In patients with clinical diagnoses of Fanconi anemia, genomic analysis resolved subtype assignment, including those of patients with inconclusive complementation test results. Eight out of 71 patients with idiopathic bone marrow failure or myelodysplastic syndrome were found to harbor damaging germline mutations in GATA2, RUNX1, DKC1, or LIG4. All 8 of these patients lacked classical clinical stigmata or laboratory findings of these syndromes and only 4 had a family history suggestive of inherited disease. These results reflect the extensive genetic heterogeneity and phenotypic complexity of bone marrow failure/myelodysplastic syndrome phenotypes. This study supports the integration of broad unbiased genetic screening into the diagnostic workup of children and young adults with bone marrow failure and myelodysplastic syndromes. PMID:25239263

Reproducibility and responsiveness of quality of life assessment and six minute walk test in elderly heart failure patients.

PubMed

O'Keeffe, S T; Lye, M; Donnellan, C; Carmichael, D N

1998-10-01

To examine the reproducibility and responsiveness to change of a six minute walk test and a quality of life measure in elderly patients with heart failure. Longitudinal within patient study. 60 patients with heart failure (mean age 82 years) attending a geriatric outpatient clinic, 45 of whom underwent a repeat assessment three to eight weeks later. Subjects underwent a standardised six minute walk test and completed the chronic heart failure questionnaire (CHQ), a heart failure specific quality of life questionnaire. Intraclass correlation coefficients (ICC) were calculated using a random effects one way analysis of variance as a measure of reproducibility. Guyatt's responsiveness coefficient and effect sizes were calculated as measures of responsiveness to change. 24 patients reported no major change in cardiac status, while seven had deteriorated and 14 had improved between the two clinic visits. Reproducibility was satisfactory (ICC > 0.75) for the six minute walk test, for the total CHQ score, and for the dyspnoea, fatigue, and emotion domains of the CHQ. Effect sizes for all measures were large (> 0.8), and responsiveness coefficients were very satisfactory (> 0.7). Effect sizes for detecting deterioration were greater than those for detecting improvement. Quality of life assessment and a six minute walk test are reproducible and responsive measures of cardiac status in frail, very elderly patients with heart failure.

Matrix Dominated Failure of Fiber-Reinforced Composite Laminates Under Static and Dynamic Loading

NASA Astrophysics Data System (ADS)

Schaefer, Joseph Daniel

Hierarchical material systems provide the unique opportunity to connect material knowledge to solving specific design challenges. Representing the quickest growing class of hierarchical materials in use, fiber-reinforced polymer composites (FRPCs) offer superior strength and stiffness-to-weight ratios, damage tolerance, and decreasing production costs compared to metals and alloys. However, the implementation of FRPCs has historically been fraught with inadequate knowledge of the material failure behavior due to incomplete verification of recent computational constitutive models and improper (or non-existent) experimental validation, which has severely slowed creation and development. Noted by the recent Materials Genome Initiative and the Worldwide Failure Exercise, current state of the art qualification programs endure a 20 year gap between material conceptualization and implementation due to the lack of effective partnership between computational coding (simulation) and experimental characterization. Qualification processes are primarily experiment driven; the anisotropic nature of composites predisposes matrix-dominant properties to be sensitive to strain rate, which necessitates extensive testing. To decrease the qualification time, a framework that practically combines theoretical prediction of material failure with limited experimental validation is required. In this work, the Northwestern Failure Theory (NU Theory) for composite lamina is presented as the theoretical basis from which the failure of unidirectional and multidirectional composite laminates is investigated. From an initial experimental characterization of basic lamina properties, the NU Theory is employed to predict the matrix-dependent failure of composites under any state of biaxial stress from quasi-static to 1000 s-1 strain rates. It was found that the number of experiments required to characterize the strain-rate-dependent failure of a new composite material was reduced by an order of

Comparative evaluation of 3 microbond strength tests using 4 adhesive systems: Mechanical, finite element, and failure analysis.

PubMed

Campos, Roberto E; Santos Filho, Paulo César F; de O Júnior, Osmir Batista; Ambrosano, Gláucia M B; Pereira, Cristina Alves

2018-01-01

Bond strength (BS) values from in vitro studies are useful when dentists are selecting an adhesive system, but there is no ideal measuring method. The purpose of this in vitro study was to investigate the influence of the evaluation method in the BS between dentin and composite resin. Molars with exposed superficial dentin (N=240) were divided into 3 groups according to the test: microtensile (μTBS), microshear (μSBS), and micropush-out (μPBS). Each one was subdivided into 4 groups according to the adhesive system: total etch, 3- and 2-step; and self-etch, 2- and 1-step). For the μPBS test, a conical cavity was prepared and restored with composite resin. An occlusal slice (1.5 mm in thickness) was obtained from each tooth. For the μSBS test, a composite resin cylinder (1 mm in diameter) was built on the dentin surface of each tooth. For the μTBS test, a 2-increment composite resin cylinder was built on the dentin surface, and beams with a sectional area of 0.5 mm 2 were obtained. Each subgroup was divided into 2 (n=10) as the specimens were tested after 7 days and 1 year of water storage. The specimens were submitted to load, and the failure recorded in units of megapascals. Original BS values from the μTBS and μSBS tests were normalized for the area from μPBS specimens. Original and normalized results were submitted to a 3-way ANOVA (α=.05). The correlation among mechanical results, stress distribution, and failure pattern was investigated. Significant differences (P<.05) were found among the adhesive systems and methods within both the original and normalized data but not between the storage times (P>.05). Within the 7 days of storage, the original BS values from μTBS were significantly higher (P<.001) than those from μPBS and μSBS. After 1 year, μSBS presented significantly lower results (P<.001). However, after the normalization for area, the BS values of the μTBS and μPBS tests were similar, and both were higher (P<.001) than that of �

Concurrent validity and clinical usefulness of several individually administered tests of children's social-emotional cognition.

PubMed

McKown, Clark

2007-03-01

In this study, the validity of 5 tests of children's social-emotional cognition, defined as their encoding, memory, and interpretation of social information, was tested. Participants were 126 clinic-referred children between the ages of 5 and 17. All 5 tests were evaluated in terms of their (a) concurrent validity, (b) incremental validity, and (c) clinical usefulness in predicting social functioning. Tests included measures of nonverbal sensitivity, social language, and social problem solving. Criterion measures included parent and teacher report of social functioning. Analyses support the concurrent validity of all measures, and the incremental validity and clinical usefulness of tests of pragmatic language and problem solving.

Reliability and validity of two isometric squat tests.

PubMed

Blazevich, Anthony J; Gill, Nicholas; Newton, Robert U

2002-05-01

The purpose of the present study was first to examine the reliability of isometric squat (IS) and isometric forward hack squat (IFHS) tests to determine if repeated measures on the same subjects yielded reliable results. The second purpose was to examine the relation between isometric and dynamic measures of strength to assess validity. Fourteen male subjects performed maximal IS and IFHS tests on 2 occasions and 1 repetition maximum (1-RM) free-weight squat and forward hack squat (FHS) tests on 1 occasion. The 2 tests were found to be highly reliable (intraclass correlation coefficient [ICC](IS) = 0.97 and ICC(IFHS) = 1.00). There was a strong relation between average IS and 1-RM squat performance, and between IFHS and 1-RM FHS performance (r(squat) = 0.77, r(FHS) = 0.76; p < 0.01), but a weak relation between squat and FHS test performances (r < 0.55). There was also no difference between observed 1-RM values and those predicted by our regression equations. Errors in predicting 1-RM performance were in the order of 8.5% (standard error of the estimate [SEE] = 13.8 kg) and 7.3% (SEE = 19.4 kg) for IS and IFHS respectively. Correlations between isometric and 1-RM tests were not of sufficient size to indicate high validity of the isometric tests. Together the results suggest that IS and IFHS tests could detect small differences in multijoint isometric strength between subjects, or performance changes over time, and that the scores in the isometric tests are well related to 1-RM performance. However, there was a small error when predicting 1-RM performance from isometric performance, and these tests have not been shown to discriminate between small changes in dynamic strength. The weak relation between squat and FHS test performance can be attributed to differences in the movement patterns of the tests

Successful MPPF Pneumatics Verification and Validation Testing

NASA Image and Video Library

2017-03-28

Engineers and technicians completed verification and validation testing of several pneumatic systems inside and outside the Multi-Payload Processing Facility (MPPF) at NASA's Kennedy Space Center in Florida. In view is the service platform for Orion spacecraft processing. The MPPF will be used for offline processing and fueling of the Orion spacecraft and service module stack before launch. Orion also will be de-serviced in the MPPF after a mission. The Ground Systems Development and Operations Program (GSDO) is overseeing upgrades to the facility. The Engineering Directorate led the recent pneumatic tests.

Urine specimen validity test for drug abuse testing in workplace and court settings.

PubMed

Lin, Shin-Yu; Lee, Hei-Hwa; Lee, Jong-Feng; Chen, Bai-Hsiun

2018-01-01

In recent decades, urine drug testing in the workplace has become common in many countries in the world. There have been several studies concerning the use of the urine specimen validity test (SVT) for drug abuse testing administered in the workplace. However, very little data exists concerning the urine SVT on drug abuse tests from court specimens, including dilute, substituted, adulterated, and invalid tests. We investigated 21,696 submitted urine drug test samples for SVT from workplace and court settings in southern Taiwan over 5 years. All immunoassay screen-positive urine specimen drug tests were confirmed by gas chromatography/mass spectrometry. We found that the mean 5-year prevalence of tampering (dilute, substituted, or invalid tests) in urine specimens from the workplace and court settings were 1.09% and 3.81%, respectively. The mean 5-year percentage of dilute, substituted, and invalid urine specimens from the workplace were 89.2%, 6.8%, and 4.1%, respectively. The mean 5-year percentage of dilute, substituted, and invalid urine specimens from the court were 94.8%, 1.4%, and 3.8%, respectively. No adulterated cases were found among the workplace or court samples. The most common drug identified from the workplace specimens was amphetamine, followed by opiates. The most common drug identified from the court specimens was ketamine, followed by amphetamine. We suggest that all urine specimens taken for drug testing from both the workplace and court settings need to be tested for validity. Copyright © 2017. Published by Elsevier B.V.

Examining the Potential for Gender Bias in the Prediction of Symptom Validity Test Failure by MMPI-2 Symptom Validity Scale Scores

ERIC Educational Resources Information Center

Lee, Tayla T. C.; Graham, John R.; Sellbom, Martin; Gervais, Roger O.

2012-01-01

Using a sample of individuals undergoing medico-legal evaluations (690 men, 519 women), the present study extended past research on potential gender biases for scores of the Symptom Validity (FBS) scale of the Minnesota Multiphasic Personality Inventory-2 by examining score- and item-level differences between men and women and determining the…

Applying Independent Verification and Validation to Automatic Test Equipment

NASA Technical Reports Server (NTRS)

Calhoun, Cynthia C.

1997-01-01

This paper describes a general overview of applying Independent Verification and Validation (IV&V) to Automatic Test Equipment (ATE). The overview is not inclusive of all IV&V activities that can occur or of all development and maintenance items that can be validated and verified, during the IV&V process. A sampling of possible IV&V activities that can occur within each phase of the ATE life cycle are described.

The Michigan Alcoholism Screening Test (MAST): A Statistical Validation Analysis

ERIC Educational Resources Information Center

Laux, John M.; Newman, Isadore; Brown, Russ

2004-01-01

This study extends the Michigan Alcoholism Screening Test (MAST; M. L. Selzer, 1971) literature base by examining 4 issues related to the validity of the MAST scores. Specifically, the authors examine the validity of the MAST scores in light of the presence of impression management, participant demographic variables, and item endorsement…

Validation of Linguistic and Communicative Oral Language Tests for Spanish-English Bilingual Programs.

ERIC Educational Resources Information Center

Politzer, Robert L.; And Others

1983-01-01

The development, administration, and scoring of a communicative test and its validation with tests of linguistic and sociolinguistic competence in English and Spanish are reported. Correlation with measures of home language use and school achievement are also presented, and issues of test validation for bilingual programs are discussed. (MSE)

Analytical validation of a psychiatric pharmacogenomic test.

PubMed

Jablonski, Michael R; King, Nina; Wang, Yongbao; Winner, Joel G; Watterson, Lucas R; Gunselman, Sandra; Dechairo, Bryan M

2018-05-01

The aim of this study was to validate the analytical performance of a combinatorial pharmacogenomics test designed to aid in the appropriate medication selection for neuropsychiatric conditions. Genomic DNA was isolated from buccal swabs. Twelve genes (65 variants/alleles) associated with psychotropic medication metabolism, side effects, and mechanisms of actions were evaluated by bead array, MALDI-TOF mass spectrometry, and/or capillary electrophoresis methods (GeneSight Psychotropic, Assurex Health, Inc.). The combinatorial pharmacogenomics test has a dynamic range of 2.5-20 ng/μl of input genomic DNA, with comparable performance for all assays included in the test. Both the precision and accuracy of the test were >99.9%, with individual gene components between 99.4 and 100%. This study demonstrates that the combinatorial pharmacogenomics test is robust and reproducible, making it suitable for clinical use.

Definition and Demonstration of a Methodology for Validating Aircraft Trajectory Predictors

NASA Technical Reports Server (NTRS)

Vivona, Robert A.; Paglione, Mike M.; Cate, Karen T.; Enea, Gabriele

2010-01-01

This paper presents a new methodology for validating an aircraft trajectory predictor, inspired by the lessons learned from a number of field trials, flight tests and simulation experiments for the development of trajectory-predictor-based automation. The methodology introduces new techniques and a new multi-staged approach to reduce the effort in identifying and resolving validation failures, avoiding the potentially large costs associated with failures during a single-stage, pass/fail approach. As a case study, the validation effort performed by the Federal Aviation Administration for its En Route Automation Modernization (ERAM) system is analyzed to illustrate the real-world applicability of this methodology. During this validation effort, ERAM initially failed to achieve six of its eight requirements associated with trajectory prediction and conflict probe. The ERAM validation issues have since been addressed, but to illustrate how the methodology could have benefited the FAA effort, additional techniques are presented that could have been used to resolve some of these issues. Using data from the ERAM validation effort, it is demonstrated that these new techniques could have identified trajectory prediction error sources that contributed to several of the unmet ERAM requirements.

Acoustic-Structure Interaction in Rocket Engines: Validation Testing

NASA Technical Reports Server (NTRS)

Davis, R. Benjamin; Joji, Scott S.; Parks, Russel A.; Brown, Andrew M.

2009-01-01

While analyzing a rocket engine component, it is often necessary to account for any effects that adjacent fluids (e.g., liquid fuels or oxidizers) might have on the structural dynamics of the component. To better characterize the fully coupled fluid-structure system responses, an analytical approach that models the system as a coupled expansion of rigid wall acoustic modes and in vacuo structural modes has been proposed. The present work seeks to experimentally validate this approach. To experimentally observe well-coupled system modes, the test article and fluid cavities are designed such that the uncoupled structural frequencies are comparable to the uncoupled acoustic frequencies. The test measures the natural frequencies, mode shapes, and forced response of cylindrical test articles in contact with fluid-filled cylindrical and/or annular cavities. The test article is excited with a stinger and the fluid-loaded response is acquired using a laser-doppler vibrometer. The experimentally determined fluid-loaded natural frequencies are compared directly to the results of the analytical model. Due to the geometric configuration of the test article, the analytical model is found to be valid for natural modes with circumferential wave numbers greater than four. In the case of these modes, the natural frequencies predicted by the analytical model demonstrate excellent agreement with the experimentally determined natural frequencies.

Measurement of Dietary Restraint: Validity Tests of Four Questionnaires

PubMed Central

Williamson, Donald A.; Martin, Corby K.; York-Crowe, Emily; Anton, Stephen D.; Redman, Leanne M.; Han, Hongmei; Ravussin, Eric

2007-01-01

This study tested the validity of four measures of dietary restraint: Dutch Eating Behavior Questionnaire, Eating Inventory (EI), Revised Restraint Scale (RS), and the Current Dieting Questionnaire. Dietary restraint has been implicated as a determinant of overeating and binge eating. Conflicting findings have been attributed to different methods for measuring dietary restraint. The validity of four self-report measures of dietary restraint and dieting behavior was tested using: 1) factor analysis, 2) changes in dietary restraint in a randomized controlled trial of different methods to achieve calorie restriction, and 3) correlation of changes in dietary restraint with an objective measure of energy balance, calculated from the changes in fat mass and fat-free mass over a six-month dietary intervention. Scores from all four questionnaires, measured at baseline, formed a dietary restraint factor, but the RS also loaded on a binge eating factor. Based on change scores, the EI Restraint scale was the only measure that correlated significantly with energy balance expressed as a percentage of energy require d for weight maintenance. These findings suggest that that, of the four questionnaires tested, the EI Restraint scale was the most valid measure of the intent to diet and actual caloric restriction. PMID:17101191

Intratester Reliability and Construct Validity of a Hip Abductor Eccentric Strength Test.

PubMed

Brindle, Richard A; Ebaugh, David; Milner, Clare E

2018-06-06

Side-lying hip abductor strength tests are commonly used to evaluate muscle strength. In a "break" test, the tester applies sufficient force to lower the limb to the table while the patient resists. The peak force is postulated to occur while the leg is lowering, thus representing the participant's eccentric muscle strength. However, it is unclear whether peak force occurs before or after the leg begins to lower. To determine intrarater reliability and construct validity of a hip abductor eccentric strength test. Intrarater reliability and construct validity study. Twenty healthy adults (26 [6] y; 1.66 [0.06] m; 62.2 [8.0] kg) made 2 visits to the laboratory at least 1 week apart. During the hip abductor eccentric strength test, a handheld dynamometer recorded peak force and time to peak force, and limb position was recorded via a motion capture system. Intrarater reliability was determined using intraclass correlation, SEM, and minimal detectable difference. Construct validity was assessed by determining if peak force occurred after the start of the lowering phase using a 1-sample t test. The hip abductor eccentric strength test had substantial intrarater reliability (intraclass correlation (3,3)  = .88; 95% confidence interval, .65-.95), SEM of 0.9 %BWh, and a minimal detectable difference of 2.5 %BWh. Construct validity was established as peak force occurred 2.1 (0.6) seconds (range: 0.7-3.7 s) after the start of the lowering phase of the test (P ≤ .001). The hip abductor eccentric strength test is a valid and reliable measure of eccentric muscle strength. This test may be used clinically to assess changes in eccentric muscle strength over time.

Repeat six-minute walk tests in patients with chronic heart failure: are they clinically necessary?

PubMed

Adsett, Julie; Mullins, Robert; Hwang, Rita; Hogden, Amy; Gibson, Ellen; Houlihan, Kylie; Tuppin, Michael; Korczyk, Dariusz; Mallitt, Kylie-Ann; Mudge, Alison

2011-08-01

Owing to a reported learning effect in patients with chronic cardiopulmonary disease, performance of at least two six-minute walk tests (6MWT) are recommended as standard practice. Patients with chronic heart failure (CHF) are typically elderly and frail and it is unknown whether current guidelines are practical in a clinical setting. The aim of this study was to determine whether repeat performance of 6MWTs in patients with CHF is related to between-test interval or baseline performance. This was a multisite observational study enrolling participants entering into heart failure rehabilitation programmes. Participants performed two 6MWTs with randomly allocated inter-test intervals between 15 and 90 minutes. Distance walked in the second test was compared with the first test using a paired t test. Eighty-eight participants (45 females, age 65 ± 14 years) with stable CHF were enrolled. Mean distance walked increased from 301 metres in test 1 to 313 metres in test 2 (p < 0.001). No significant change was recorded between test 1 and test 2 for those whose baseline distance was <300 metres. The interval between tests had no significant effect on the distance walked. The change in 6MWT distance was significantly associated with better baseline performance but not with the interval between tests.

Predictive validity of the Biomedical Admissions Test: an evaluation and case study.

PubMed

McManus, I C; Ferguson, Eamonn; Wakeford, Richard; Powis, David; James, David

2011-01-01

There has been an increase in the use of pre-admission selection tests for medicine. Such tests need to show good psychometric properties. Here, we use a paper by Emery and Bell [2009. The predictive validity of the Biomedical Admissions Test for pre-clinical examination performance. Med Educ 43:557-564] as a case study to evaluate and comment on the reporting of psychometric data in the field of medical student selection (and the comments apply to many papers in the field). We highlight pitfalls when reliability data are not presented, how simple zero-order associations can lead to inaccurate conclusions about the predictive validity of a test, and how biases need to be explored and reported. We show with BMAT that it is the knowledge part of the test which does all the predictive work. We show that without evidence of incremental validity it is difficult to assess the value of any selection tests for medicine.

The Predictive Validity of the Metropolitan Readiness Tests, 1976 Edition.

ERIC Educational Resources Information Center

Nagle, Richard J.

1979-01-01

A sample of 176 first-grade children was tested on the Metropolitan Readiness Tests, 1976 Edition (MRT), during the initial month of school and was retested eight months later on the Stanford Achievement Test. Results demonstrated substantial validity of the MRT for predicting first-grade achievement. (Author/CTM)

Validation testing of a soil macronutrient sensing system

USDA-ARS?s Scientific Manuscript database

Rapid on-site measurements of soil macronutrients (i.e., nitrogen, phosphorus, and potassium) are needed for site-specific crop management, where fertilizer nutrient application rates are adjusted spatially based on local requirements. This study reports on validation testing of a previously develop...

Controls on radon emission from granite as evidenced by compression testing to failure

NASA Astrophysics Data System (ADS)

Koike, Katsuaki; Yoshinaga, Tohru; Suetsugu, Kenta; Kashiwaya, Koki; Asaue, Hisafumi

2015-10-01

A set of uniaxial compression tests of granite specimens taken from five localities across Japan was conducted to identify the factors controlling the quantity of radon (Rn) emission (sum of 222Rn and 220Rn) during compression and failure. An α-scintillation detector and a gas flow unit were installed with a testing machine to enable continuous measurement of Rn emissions. Common to all specimens, Rn emissions remained at or slightly declined from the background level after the start of loading; this is similar to the natural phenomenon of decline in groundwater-dissolved Rn before an earthquake. Closure of original microcracks is the most likely cause of the initial Rn decline. Then, Rn emissions begin to increase at 46-57 per cent stress level to the uniaxial compressive strength, and continue to increase even after the failure of specimen. This commencement stress level is close to the general stress level at outbreak of acoustic emissions caused by the development and connection of microcracks. The Rn increase after failure is similar to a phenomenon observed in aftershocks, which may originate from the enhancement of Rn emanations from grains due to the large increase in total surface area and stress release. In addition to the initial radioelement content in rock, the failure pattern (conjugate shear versus longitudinal tensile type), compressive strength, and grain size are possible control factors of the maximum quantity of Rn emissions induced by failure. This maximum may also be affected by the development velocity of the emanation area, which is related to the Rn emanation fraction, associated with the fragmentation. In addition to the magnitude of an earthquake and its hypocentre distance to Rn detectors, the magnitude of increase in Rn concentration in soil gas and groundwater before, during, and after an earthquake in crystalline rocks depends on the intrinsic radioelement content, the mineral texture, and the mechanical properties of rocks. Rock

Validation of biological activity testing procedure of recombinant human interleukin-7.

PubMed

Lutsenko, T N; Kovalenko, M V; Galkin, O Yu

2017-01-01

Validation procedure for method of monitoring the biological activity of reсombinant human interleukin-7 has been developed and conducted according to the requirements of national and international recommendations. This method is based on the ability of recombinant human interleukin-7 to induce proliferation of T lymphocytes. It has been shown that to control the biological activity of recombinant human interleukin-7 peripheral blood mononuclear cells (PBMCs) derived from blood or cell lines can be used. Validation charac­teristics that should be determined depend on the method, type of product or object test/measurement and biological test systems used in research. The validation procedure for the method of control of biological activity of recombinant human interleukin-7 in peripheral blood mononuclear cells showed satisfactory results on all parameters tested such as specificity, accuracy, precision and linearity.

Federal COBOL Compiler Testing Service Compiler Validation Request Information.

DTIC Science & Technology

1977-05-09

background of the Federal COBOL Compiler Testing Service which was set up by a memorandum of agreement between the National Bureau of Standards and the...Federal Standard, and the requirement of COBOL compiler validation in the procurement process. It also contains a list of all software products...produced by the software Development Division in support of the FCCTS as well as the Validation Summary Reports produced as a result of discharging the

Validity of the Eating Attitudes Test and the Eating Disorders Inventory in Bulimia Nervosa.

ERIC Educational Resources Information Center

Gross, Janet; And Others

1986-01-01

Assessed criterion and concurrent validity of the Eating Attitudes Test and the Eating Disorder Inventory in 82 women with bulimia nervosa. Both tests demonstrated criterion validity by discriminating bulimia nervosa subjects from normals. Only weak support was found for concurrent validity within bulimia subjects. Recommends combination of…

Impact on Participation and Autonomy: Test of Validity and Reliability for Older Persons.

PubMed

Hammar, Isabelle Ottenvall; Ekelund, Christina; Wilhelmson, Katarina; Eklund, Kajsa

2014-11-06

In research and healthcare it is important to measure older persons' self-determination in order to improve their possibilities to decide for themselves in daily life. The questionnaire Impact on Participation and Autonomy (IPA) assesses self-determination, but is not constructed for older persons. The aim of this study was to examine the validity and reliability of the IPA-S questionnaire for persons aged 70 years and older. The study was performed in two steps; first a validity test of the Swedish version of the questionnaire, IPA-S, followed by a reliability test-retest of an adjusted version. The validity was tested with focus groups and individual interviews on persons aged 77-88 years, and the reliability on persons aged 70-99 years. The validity test result showed that IPA-S is valid for older persons but it was too extensive and the phrasing of the items needed adjustments. The reliability test-retest on the adjusted questionnaire, IPA- Older persons (IPA-O), showed that 15 of 22 items had high agreement. IPA-O can be used to measure older persons' self-determination in their care and rehabilitation.

Standard intelligence tests are valid instruments for measuring the intellectual potential of urban children: comments on pitfalls in the measurement of intelligence.

PubMed

Sattler, J M

1979-05-01

Hardy, Welcher, Mellitis, and Kagan altered standard WISC administrative and scoring procedures and, from the resulting higher subtest scores, concluded that IQs based on standardized tests are inappropriate measures for inner-city children. Careful examination of their study reveals many methodological inadequacies and problematic interpretations. Three of these are as follows: (a) failure to use any external criterion to evaluate the validity of their testing-of-limits procedures; (b) the possibility of examiner and investigator bias; and (c) lack of any comparison group that might demonstrate that poor children would be helped more than others by the probes recommended. Their report creates misleading doubts about existing intelligence tests and does a disservice to inner-city children who need the benefits of the judicious use of diagnostic procedures, which include standardized intelligence tests. Consequently, their assertion concerning the inappropriateness of standardized test results for inner-city children is not only premature and misleading, but it is unwarranted as well.

Validity and the Consequences of Test Interpretation and Use

ERIC Educational Resources Information Center

Hubley, Anita M.; Zumbo, Bruno D.

2011-01-01

The vast majority of measures have, at their core, a purpose of personal and social change. If test developers and users want measures to have personal and social consequences and impact, then it is critical to consider the consequences and side effects of measurement in the validation process itself. The consequential basis of test interpretation…

An entropy-based nonparametric test for the validation of surrogate endpoints.

PubMed

Miao, Xiaopeng; Wang, Yong-Cheng; Gangopadhyay, Ashis

2012-06-30

We present a nonparametric test to validate surrogate endpoints based on measure of divergence and random permutation. This test is a proposal to directly verify the Prentice statistical definition of surrogacy. The test does not impose distributional assumptions on the endpoints, and it is robust to model misspecification. Our simulation study shows that the proposed nonparametric test outperforms the practical test of the Prentice criterion in terms of both robustness of size and power. We also evaluate the performance of three leading methods that attempt to quantify the effect of surrogate endpoints. The proposed method is applied to validate magnetic resonance imaging lesions as the surrogate endpoint for clinical relapses in a multiple sclerosis trial. Copyright © 2012 John Wiley & Sons, Ltd.

Validation of the German version of the Ford Insomnia Response to Stress Test.

PubMed

Dieck, Arne; Helbig, Susanne; Drake, Christopher L; Backhaus, Jutta

2018-06-01

The purpose of this study was to assess the psychometric properties of a German version of the Ford Insomnia Response to Stress Test with groups with and without sleep problems. Three studies were analysed. Data set 1 was based on an initial screening for a sleep training program (n = 393), data set 2 was based on a study to test the test-retest reliability of the Ford Insomnia Response to Stress Test (n = 284) and data set 3 was based on a study to examine the influence of competitive sport on sleep (n = 37). Data sets 1 and 2 were used to test internal consistency, factor structure, convergent validity, discriminant validity and test-retest reliability of the Ford Insomnia Response to Stress Test. Content validity was tested using data set 3. Cronbach's alpha of the Ford Insomnia Response to Stress Test was good (α = 0.80) and test-retest reliability was satisfactory (r = 0.72). Overall, the one-factor model showed the best fit. Furthermore, significant positive correlations between the Ford Insomnia Response to Stress Test and impaired sleep quality, depression and stress reactivity were in line with the expectations regarding the convergent validity. Subjects with sleep problems had significantly higher scores in the Ford Insomnia Response to Stress Test than subjects without sleep problems (P < 0.01). Competitive athletes with higher scores in the Ford Insomnia Response to Stress Test had significantly lower sleep quality (P = 0.01), demonstrating that vulnerability for stress-induced sleep disturbances accompanies poorer sleep quality in stressful episodes. The findings show that the German version of the Ford Insomnia Response to Stress Test is a reliable and valid questionnaire to assess the vulnerability to stress-induced sleep disturbances. © 2017 European Sleep Research Society.

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.

Testing and Failure Mechanisms of Ice Phase Change Material Heat Exchangers

NASA Technical Reports Server (NTRS)

Leimkuehler, Thomas O.; Stephan, Ryan A.; Hawkins-Reynolds, Ebony

2010-01-01

Phase change materials (PCM) may be useful for thermal control systems that involve cyclical heat loads or cyclical thermal environments such as Low Earth Orbit (LEO) and Low Lunar Orbit (LLO). Thermal energy can be stored in the PCM during peak heat loads or in adverse thermal environments. The stored thermal energy can then be released later during minimum heat loads or in more favorable thermal environments. One advantage that PCM s have over evaporators in this scenario is that they do not use a consumable. The use of water as a PCM rather than the more traditional paraffin wax has the potential for significant mass reduction since the latent heat of formation of water is approximately 70% greater than that of wax. One of the potential drawbacks of using ice as a PCM is its potential to rupture its container as water expands upon freezing. In order to develop a space qualified ice PCM heat exchanger, failure mechanisms must first be understood. Therefore, a methodical experimental investigation has been undertaken to demonstrate and document specific failure mechanisms due to ice expansion in the PCM. A number of ice PCM heat exchangers were fabricated and tested. Additionally, methods for controlling void location in order to reduce the risk of damage due to ice expansion were investigated. This paper presents the results of testing that occurred from March through September of 2010 and builds on testing that occurred during the previous year.

Validity of a novel computerized screening test system for mild cognitive impairment.

PubMed

Park, Jin-Hyuck; Jung, Minye; Kim, Jongbae; Park, Hae Yean; Kim, Jung-Ran; Park, Ji-Hyuk

2018-06-20

ABSTRACTBackground:The mobile screening test system for screening mild cognitive impairment (mSTS-MCI) was developed for clinical use. However, the clinical usefulness of mSTS-MCI to detect elderly with MCI from those who are cognitively healthy has yet to be validated. Moreover, the comparability between this system and traditional screening tests for MCI has not been evaluated. The purpose of this study was to examine the validity and reliability of the mSTS-MCI and confirm the cut-off scores to detect MCI. The data were collected from 107 healthy elderly people and 74 elderly people with MCI. Concurrent validity was examined using the Korean version of Montreal Cognitive Assessment (MoCA-K) as a gold standard test, and test-retest reliability was investigated using 30 of the study participants at four-week intervals. The sensitivity, specificity, positive predictive value, and negative predictive value (NPV) were confirmed through Receiver Operating Characteristic (ROC) analysis, and the cut-off scores for elderly people with MCI were identified. Concurrent validity showed statistically significant correlations between the mSTS-MCI and MoCA-K and test-rests reliability indicated high correlation. As a result of screening predictability, the mSTS-MCI had a higher NPV than the MoCA-K. The mSTS-MCI was identified as a system with a high degree of validity and reliability. In addition, the mSTS-MCI showed high screening predictability, indicating it can be used in the clinical field as a screening test system for mild cognitive impairment.