Performance-based Testing Research Articles

ANALISIS FAIRNESS DAN INCENTIVE CONTRACTING PADA KINERJA BERBASIS ANGGARAN ATAS PENGUJIAN: EKSPERIMEN (STUDI KASUS PADA MAHASISWA PASCASARJANA DIUNIVERSITAS MALIKUSSALEH TANUN 2017- 2018)

This study aimed to determine the analysis of fairness and incentive contracting on performance-based budget testing experiments. The data used in this research were primary data. The population in this study consisted of 59 postgraduate students who were on Lancang Garam St, postgraduate campus of Malikussaleh University with an observation period starting from 2017-2018. The sampling method was purposive sampling. The number of samples that meet the research criteria based on existing considerations was that all postgraduate students management in science during 2017-2018 as many as 59 respondents. The method used to analyze the relationship between independent variables and the dependent variable was Multiple linear regression analysis and Classical assumption test. The test results showed that the planning variable was accepted because the value was significantly higher, namely the difference between fairness and budget-based performance, while the other side is accepted also because it was seen from a significantly higher value that was with the difference between fairness towards the budget process, which has been studied from 59 students on the postgraduate campus of Malikussaleh University.

Performance-based testing for ICT skills assessing: a case study of students and teachers’ ICT skills in Finnish schools

Skills enabling and ensuring universal access to information have been investigated intensively during the past few years. The research results provide knowledge on the differences and digital divides. When examining ICT skill levels, the accuracy of assessment is one of the key issues to address the results and gain the applicable data for appropriate interventions to enhance digital inclusion. To date, ICT skill assessment is based mainly on self-reports and subjective evaluations. However, as previous studies have shown, people tend to overrate or underrate their own levels of competence. Thus, novel performance-based approach for assessing ICT skills is presented in this paper. The ICT skill test contains 42 tasks grouped into 17 ICT fields. The study was conducted with upper comprehensive and upper secondary level school students (n = 3159) and their teachers (n = 626) during years 2014–2016 in Finland. Using factor analysis, three ICT skills factors were created: basic digital skills, advanced technical skills, and professional ICT skills. The performance in the ICT skill test was also divided by gender, as the male students and teachers outperformed the female students and teacher. Outperformance also occurred by educational level, as both upper secondary level students and teachers were seen as possessing higher-level ICT skills than students and teachers at the comprehensive level. We thus argue that to compare the ICT skills and the validity of the assessments, we needed to ensure consistent assessment for both students and teachers. In addition, in order to diminish the ICT skill gap among students, interventions using formal education are urgently needed, and in particular, more attention should be given to both teacher training and in-service training.

Performance Evaluations of Three Silt Fence Practices Using a Full-Scale Testing Apparatus

Erosion and sediment controls on construction sites minimize environmental impacts from sediment-laden stormwater runoff. Silt fence, a widely specified perimeter control practice on construction projects used to retain sediment on-site, has limited performance-based testing data. Silt fence failures and resultant sediment losses are often the result of structural failure. To better understand silt fence performance, researchers at the Auburn University-Erosion and Sediment Control Testing Facility (AU-ESCTF) have evaluated three silt fence options to determine possible shortcomings using standardized full-scale testing methods. These methods subject silt fence practices to simulated, in-field conditions typically experienced on-site without the variability of field testing or the limited application of small-scale testing. Three different silt fence practices were tested to evaluate performance, which included: (1) Alabama Department of Transportation (ALDOT) Trenched Silt Fence, (2) ALDOT Sliced Silt Fence, and (3) Alabama Soil and Water Conservation Committee (AL-SWCC) Trenched Silt Fence. This study indicates that the structural performance of a silt fence perimeter control is the most important performance factor in retaining sediment. The sediment retention performance of these silt fence practices was 82.7%, 66.9% and 90.5%, respectively. When exposed to large impoundment conditions, both ALDOT Trench and Sliced Silt Fence practices failed structurally, while the AL-SWCC Trenched Silt Fence did not experience structural failure.

Cementitious materials for construction-scale 3D printing: Laboratory testing of fresh printing mixture

In this study, a framework for performance-based laboratory testing of cementitious mixtures for construction-scale 3D printing is developed, where workability of a fresh “printing mixture” is studied in terms of print quality, shape stability, and printability window. Print quality is described using measures of surface quality and dimensions of printed layers. Details of two proposed test methods for evaluation of shape stability, namely, “layer settlement” and “cylinder stability” are also provided. Experimental study of four different mixtures revealed that inclusion of silica fume and Nano-clay significantly enhance shape stability. The results of five conventional test methods, as well as four proposed tests are used to discuss the performance of mixtures.

Use of performance-based testing for high RAP mix design and production monitoring

In 2014 the Wisconsin Department of Transportation and industry developed a pilot programme for hot mix asphalt with higher recycled asphalt content that required use of performance tests during mix design and production. Following the balanced mix design concept mixture tests were selected to address rutting resistance after short-term ageing and durability after long-term ageing. The tests selected were the Hamburg Wheel Tracking test, the Semi-Circular Bend (SCB) test at intermediate temperature, and the Disc-Shaped Compact Tension test at low pavement temperatures. Asphalt binder extraction and grading from aged mix was also required. The focus of this paper is to summarise the mixture performance test and recovered binder data gathered during the pilot project on State Highway 77 in Ashland County, WI, suggest modifications to the SCB test procedure, and to present accelerated ageing protocols for continued use of performance testing in practice. SCB test results collected during the project at 25°C did not relate well to values published in the literature or show adequate sensitivity to changes in mix properties. The effects of test temperature and an alternative analysis method are presented. Based on the results, recommendations include use of a climate-based approach for test temperature selection and inclusion of post-peak analysis to better discriminate between mix composition and ageing conditions. Accelerated long-term-ageing protocols involving loose mix ageing at 135°C for 12 and 24 h are compared to American Association of State Highway and Transportation Officials (AASHTO) R30 compacted mix ageing using recovered binder and mixture fracture properties. Results found that 12 h loose mix ageing produced similar recovered binder grading to AASHTO R30, whereas the effect of ageing on mixture fracture tests was inconclusive. The relationship between laboratory and field ageing is investigated through comparison of field cores to laboratory-aged plant-produced mix from a project constructed in SE Minnesota in 2006. Lastly, the laboratory performance of the high recycled and conventional mix designs are compared on the basis of mixture cracking resistance and recovered asphalt binder properties after extended ageing. The high recycle mix exhibited equal or better performance relative to the conventional mix across all selected performance tests. This comparative analysis also provides an example of how the inclusion of performance testing can influence the material selection process and produce test results indicative of improved overall performance of the mix.

Relationships among psychoneurological symptoms and levels of C-reactive protein over 2years in women with early-stage breast cancer.

The aim of the present study was to explore clusters of psychoneurological symptoms and inflammation (levels of C-reactive protein) over time in a cohort of women with early-stage breast cancer. Specifically, we examined the relationships among affective symptoms (depression, anxiety, fatigue, sleep disturbances, pain, and perceived stress), domains of cognitive performance, and levels of peripheral C-reactive over a period of 2years. This was a prospective, longitudinal study of 77 women diagnosed with early-stage breast cancer. Data collection, including symptom questionnaires, performance-based cognitive testing, and blood draws, took place at 5 time points: prior to initiating adjuvant chemotherapy, prior to the fourth chemotherapy treatment, and at 6, 12, and 24months after the initiation of chemotherapy. Exploratory factor analysis with varimax orthogonal rotation was used to examine the covariance among symptoms at each visit. Using the factor scores and weighted sums, three clusters were identified: global cognition, affective symptoms, and cognitive efficiency. Peripheral levels of C-reactive protein were inversely correlated with the cognitive efficiency factor across time. The findings suggest that objectively measured domains of cognitive function occur independently of other affective symptoms that are commonly reported by women with breast cancer in long-term survivorship. The cognitive efficiency symptom cluster may be amenable to interventions targeted to biological influences that reduce levels of C-reactive protein.

Alkali–aggregate reaction: performance testing, exposure sites and regulations

Several laboratory performance tests for alkali–aggregate reaction (AAR) have been used worldwide for about 20 years. However, a review performed one of the present authors in 2006 concluded that none of the test methods meets all the criteria for an ideal performance test. In the last decade, research has been performed in several countries with the aim to improve current AAR performance test methods and develop alternative tests. The Rilem (The International Union of Laboratories and Experts in Construction Materials, Systems and Structures) Technical Committee (TC) 258-AAA (2014–2019) is also focusing on this topic. The main purpose of this technical committee is to develop and promote a reliable performance-based testing concept for the prevention of deleterious AAR. Strong emphasis will be placed on the implementation of the Rilem methods and recommendations as national and international standards. It is crucial to link the results from the accelerated laboratory testing to field behaviour, primarily against field exposure sites. Some results from such exposure sites are included in this paper.

Shear creep response of an airport asphalt mastic

Two runways were resurfaced with 50–60 mm of typical airport asphalt at the same airport. One runway surface performed well while the other exhibited a lack of resistance to cyclic shear stress under heavy aircraft braking. Both runways had the same hydrated lime filler and coarse aggregate source. The fine aggregate (dust) used to manufacture the two runway surfaces was obtained from two different basalt quarries. The dust associated with the poorly performing asphalt contained a potentially detrimental clay mineral (Hisingerite). It was subsequently determined that the crude oil used to manufacture the feedstock for the acid-modified binder also changed at the transition from one runway to the other. The changes in dust and binder were confounded. A combination of viscosity testing and performance-based multiple stress creep recovery (MSCR) testing determined that the two runway binders responded significantly differently to shear stress and aged differently with sample storage time. The differences were magnified at higher temperatures. Further, mastic samples were manufactured from binder associated with both feedstocks, in combination with dust from both quarries. MSCR testing of mastic indicated that the dust containing significant Hisingerite had no adverse impact on the mastic response to shear stress. The change in binder feedstock was concluded to be the root cause of the lack of resistance to cyclic shear stress observed in one runway surface. This occurred despite all batches of binder meeting the viscosity-based Australian specification for paving grade bitumen. The specification has no mechanism to prevent similar changes in bitumen feedstock affecting airport bitumen performance in the future. Incorporating performance-based testing in the Australian bitumen specification is recommended.

Neuropsychological assessment in adolescents with anorexia nervosa - exploring the relationship between self-report and performance-based testing.

ObjectiveResearch investigating the relationship between neuropsychological test performances and self-reported cognitive functioning in patients with anorexia nervosa (AN) is limited, and existing experimental studies only demonstrate a low-to-moderate relationship between the performance based tests and everyday behaviour. The objective of the current study was to explore the association between neuropsychological test performance and self-reports of executive functioning in adolescents with AN.MethodTwenty adolescent females diagnosed with AN, aged 13 to 18, completed neuropsychological test battery “the Ravello Profile” and the self-report version of the Behaviour Rating Inventory of Executive Function (BRIEF-SR). The BRIEF Parent Form (BRIEF-PF) was employed to provide additional information of the patients’ executive functioning.ResultsBased on group level analyses, the results support the existing literature in failing to find consistent weaknesses in neuropsychological functioning in adolescents with AN. Further, with few exceptions, the Ravello Profile was insubstantially correlated with the majority of the BRIEF clinical scales, indicative of a lack of association between these two assessment methods.ConclusionThe current study accentuates the need for concern regarding the generalizability of neuropsychological assessments in adolescent patients with AN.

Outcomes 2 Years After ACLR In Athletes

Objectives:At least 175,000 Anterior Cruciate Ligament Reconstructions (ACLR) are performed yearly in the United States, with the goal of restoring static knee stabilization for full return to previous level of function. Large data registries have reported general population outcomes after ACLR, but less is known about the athletic population. The purpose of this study is to evaluate functional outcomes, return to sport rates, and re-injury rates 2 years after ACLR from an all athlete cohort and make comparisons to outcomes reported in the literature.Methods:Three hundred subjects were prospectively enrolled after ACL injury. All subjects sustained an isolated ACL injury and were enrolled within 7 months of injury. Subjects regularly participated in level I or II sports greater than 50 hours per year. All subjects underwent preoperative neuromuscular training. 201 of these subjects underwent ACLR. 157 patients returned for follow-up 2 years after surgery for performance-based and patient-reported testing. Quadriceps strength testing was completed either isometrically or isokinetically using an electromechanical dynamometer, and reported as quadriceps index (QI) [involved/uninvolved x 100]. Patient reported measures included The International Knee Documentation Committee 2000 Subjective Knee Form (IKDC2000), return to pre-injury activity (RTS), return to pre-injury activity competitive level (RTS-L), and re-injury. Statistics are expressed in means and standard deviations with T-tests or Chi-square for comparisons with values reported in literature.Results:Two year follow up QI (mean±SD: 96.94±13.4%) revealed significantly higher quadriceps index compared to Hamada 2001 (89.8±16.5%) (P<.001). IKDC2000 (90.40±11.0; median: 94) scores were higher than the median score reported by the MOON group at 2 years (median: 75). Our RTS (72%) was significantly higher than Arden et al. 2014 (65%) (P=.012), whereas, our RTS-L (55%) was similar to Arden 2014 (55%) (P=.997). Our Re-injury rate was 13.9% (19 ipsilateral, 9 contralateral) which was significantly less (P=.002) than Paterno 2014 (29.5%).Conclusion:A comprehensive pre-operative rehabilitation program including neuromuscular training, combined with a post-operative rehabilitation program resulted in higher quadriceps strength, return to sport rates, and re-injury rates in athletes 2 years after ACLR compared to recent findings in the scientific literature. These findings highlight that despite excellent clinical outcomes, ACLR does not guarantee return to sport, and re-injury rates remain high. Limitations include motivational differences in athletes compared to general populations as well as age differences compared to Paterno 2014. Further research is needed to determine how to improve return to sport competitive levels rates and reduce subsequent injury risk in athletes after ACLR.

Performance-based testing in mild stroke: identification of unmet opportunity for occupational therapy.

Age at first stroke is decreasing, and most strokes are mild to moderate in severity. Executive function (EF) deficits are increasingly recognized in the stroke population, but occupational therapists have not altered their evaluation methods to fully accommodate changing patient needs. We present a hierarchical performance-based testing (PBT) pathway using data to illustrate how PBT could identify patients with mild stroke-related EF deficits in need of occupational therapy intervention. Data suggest that a substantial number of patients with EF deficits after mild stroke could benefit from occupational therapy services.

Methodology for Evaluating Inlet Protection Practices Using Large-Scale Testing Techniques

AbstractMost roadway construction projects disturb existing vegetation exposing bare soil to environmental variables (i.e., precipitation, wind, and freeze and thaw) that cause erosion. Soil eroded during storm events is conveyed by storm water runoff and may become deposited in receiving waterways. Inlet protection practices (IPPs) are temporary erosion and sediment controls commonly used around inlet drainage structures to prevent erosion while also retaining sediment on-site. Effective IPPs impound storm water, prevent upstream channel erosion, and promote settling along the perimeter of a device. Stringent effluent regulations coupled with greater public awareness with regards to surface water pollution have created the need for understanding the performance of commonly used erosion and sediment control practices. This study developed a methodology and testing apparatus for large-scale reproducible performance-based testing of standard IPPs at the Auburn University Erosion and Sediment Control Testing...

Lessons learned in the pursuit of a dream.

The author describes a career in which he combined clinical surgery with the formal study of medical education. In the 1980s, when the author embarked on this career track, it was an uncommon pathway. Over the last 30 years there has been an exponential increase in the number of individuals who have made medical education their principal academic focus. This paper provides examples from the author's personal story and lessons derived from that experience. The author outlines his experience of attaining formal training in education and concludes that this training was a foundational element in his pursuit of a career in health education research. The author describes his involvement in the transition from paper and pencil-based tests to performance-based testing in high-stakes examinations. He describes the development of a research centre in health professions education and the establishment of a simulation centre. The author's experiences in the development of an examination intended to measure technical skills, in the adoption of surgical safety checklists and in the elaboration of a programme in competency-based education are discussed. The author describes several of the lessons learned in the course of his career in medical education. He argues that successful enterprises in scholarship in medicine are almost invariably the product of interdisciplinarity. He describes the power of a joint venture between a university and an academic hospital. He argues that the geographical footprint of an emerging centre is critical. He discusses the importance of graduate studentship in an emerging discipline and enterprise.

Functional impairment in mild cognitive impairment evidenced using performance-based measurement.

Older adults (OAs) with mild cognitive impairment (MCI) are traditionally thought to have preservation of activities of daily living (ADLs). However, recent evidence suggests OAs with MCI may have difficulty completing ADLs and specifically instrumental ADLs (IADLs). The ADLs are frequently evaluated through self- or collateral report questionnaires, while performance-based measures are infrequently utilized, despite the decreased bias and increased accuracy and sensitivity associated with these instruments. This investigation compared ADLs between community-dwelling OAs with (n = 20) and without MCI (n = 30) using a self-report questionnaire (Older American Resources and Services Activities of Daily Living Scale; OARS), a collateral report questionnaire (OARS), and a performance-based measure (the Direct Assessment of Functional Status-Revised). Consistent with our hypothesis, OAs with MCI had decreased ADLs and IADLs on the performance-based measure compared to cognitively intact OAs, while there were no differences in ADLs or IADLs on self-report questionnaires or collateral report questionnaires. Our results suggest OAs with MCI have decreased ability to complete IADLs. However, this investigation suggests these deficits may not be detected by questionnaires and are more likely to be found with performance-based testing.

Abstract NS16: Performance-based Testing Identifies Cognitive Deficits Missed by Screening Methods Used in Mild Stroke

Background: Recent data suggests that approximately 50 % of ischemic strokes are in the mild range (NIHSS ≤ 6). Persons with mild stroke have minimal motor, language or sensory impairment and often receive no rehab services. However about 30 % these patients are unable to fully return to pre-stroke roles and responsibilities due to subtle but disabling cognitive impairment. Aim: To assess the contribution of performance based testing (PBT) to the identification of executive function (EF) deficits undetected by traditional screening methods in a cohort of individuals with mild stroke reporting difficulties in participation as measured by the Stroke Impact Scale (SIS) Methods: The Impact of Mild Stroke on Community Reintegration and Quality of Life study followed a cohort of persons with first ischemic stroke with NIHSS scores ≤ 5 from acute admission to 1 yr follow-up. Neurocognitive, functional ,and self-report measures were administered at baseline, day 90, 6 mo. and 1 yr. PBTs assessing executive function were administered at 6-mo follow-up; The Executive Function Performance Test (EFPT) evaluates 4 complex IADL task s and The Multiple Errands Test (MET) requires performance of a series of tasks in a dynamic real-world environment . A score of &lt; 80 on the SIS Participation scale SIS indicates failure to fully resume roles and responsibilities. Results: 90 patients (Mdn NIHSS=3; Mean age 60 ± 10.8 ) with first ischemic stroke were evaluated . All had MRS scores ≤ 1; 89 % were independent on the FIM (≥108) and normal cognition ( Short Blessed Test ≤ 4). Of these, 39 % reported scores less than 80 on SIS Participation. The EFPT identified 46 % of this group as performing in the impaired range. Further assessment of those unimpaired on the EFPT with the more demanding MET found an additional 22 % as impaired: 68% of patients scoring as “normal” on standard measures had impaired PBT scores. Conclusions: We identified individuals with occupational therapy rehabilitation needs unrecognized by standard measures. We recommend a hierarchical approach to evaluation of persons with mild stroke reporting difficulties in participation with PBT used in those scoring unimpaired/independent on standard outcome measures

Quality and Durability of Warm Rubberized Asphalt Cement in Ontario, Canada

This paper documents and discusses an investigation of performance-based testing of asphalt cement (AC), AC modified with warm-mix technology additives (warm AC), rubberized asphalt cement (RAC), and warm RAC. A number of control, warm, and RAC binders from Ontario, Canada, construction contracts were investigated for their compliance with conventional Superpave® as well as additional specification criteria. It was found that all samples passed the Superpave requirements but only one satisfied the additional Ontario criteria. One warm AC and two field-blended RAC samples showed high levels of physical hardening, which can lead to early cracking. The warm AC lost 8°C when stored isothermally for 3 days at low temperatures according to Ontario's extended bending beam rheometer protocol (LS-308). The two RAC samples lost 10°C and 12°C following the same conditioning. Many of the investigated samples showed deficient strain tolerance as measured in Ontario's double-edge-notched tension test (LS-299). In an effort to formulate warm RAC with improved properties, a number of compositions were prepared with soft Cold Lake AC and a small quantity of naphthenic oil. These binders showed little chemical and physical hardening and reasonable critical crack tip opening displacements. Strain tolerance was much improved by coblending with a high vinyl-type styrene–butadiene–styrene polymer and a small amount of sulfur. The Ministry of Transportation of Ontario is interested in using the developed formulations in future pavement trials with expected improvements in pavement performance.

Hearing Aid Instruction Booklets: Employing Usability Testing to Determine Effectiveness

This study implemented performance-based usability and literature testing to determine whether people could use 2 instruction booklets for hearing aids (HAs) to carry out basic maintenance tasks and find and understand key facts. Using a cross-sectional study design, researchers recruited 40 participants (25 women, 15 men, ages 46-72 years) with no experience of HAs or audiology services to test instruction booklets for a Danalogic and Unitron HA (20 participants each). Participants were asked to follow instructions provided within the booklets to complete common HA tasks (e.g., cleaning the HA and mold and changing the battery) and demonstrate understanding of information. Participants' views of the booklets were then obtained within a short individual interview. Participants experienced problems in completing all tasks while following instructions provided by the Danalogic and Unitron booklets. Individual interviews highlighted further issues regarding layout, diagrams, and content, including missing information. Some HA instruction booklets contain information that some users may find difficult to find, understand, and follow. These limitations may negatively impact on HA satisfaction and use. It is recommended that written information for clients be evaluated prior to use. This study supports the premise that performance-based usability and literature testing are appropriate methods to use.

Can user testing of a clinical trial patient information sheet make it fit-for-purpose? - a randomized controlled trial

BackgroundThe participant information sheet (PIS) provided to potential trial participants is a critical part of the process of valid consent. However, there is long-standing concern that these lengthy and complex documents are not fit-for-purpose. This has been supported recently through the application of a performance-based approach to testing and improving readability called user testing. This method is now widely used to improve patient medicine leaflets - determining whether people can find and understand key facts. This study applied for the first time a controlled design to determine whether a PIS developed through user testing had improved readability over the original, using a sheet from a UK trial in acute myeloid leukemia (AML16).MethodsIn the first phase the performance of the original PIS was tested on people in the target group for the trial. There were three rounds of testing including 50 people in total - with the information revised according to its performance after each of the first 2 rounds. In the second phase, the revised PIS was compared with the original in a parallel groups randomised controlled trial (RCT) A total of 123 participants were recruited and randomly allocated to read one version of the PIS to find and show understanding of 21 key facts.ResultsThe first, developmental phase produced a revised PIS significantly altered in its wording and layout. In the second, trial phase 66% of participants who read the revised PIS were able to show understanding of all aspects of the trial, compared with 15% of those reading the original version (Odds Ratio 11.2; Chi-square = 31.5 p < .001). When asked to state a preference, 87.1% participants chose the revised PIS (Sign test p < .001).ConclusionsThe original PIS for the AML16 trial may not have enabled valid consent. Combining performance-based user testing with expertise in writing for patients and information design led to a significantly improved and preferred information sheet. User testing is an efficient method for indicating strengths and weaknesses in trial information, and Research Ethics Committees and Institutional Review Boards should consider requesting such testing, to ensure that PIS are fit-for-purpose.

Progressive Aphasia Severity Scale: Baseline and longitudinal measures in PPA and relationship to quantitative imaging biomarkers

Primary Progressive Aphasia (PPA) is a heterogeneous clinical syndrome characterized by deterioration of speech/language abilities. Efficacious treatments are lacking, partly due to the need for standardized methods to monitor symptom progression. To address this, we developed the Progressive Aphasia Severity Scale (PASS) to rate presence and severity of impairment in ten domains of language. In addition, sensitive and specific imaging biomarkers will likely be crucial as inclusion/exclusion criteria and for measuring the potential effects of putative disease-modifying interventions. We are working on both types of measures to determine their utility for longitudinal studies. “MsoNormal” > Patients with PPA were rated at baseline and longitudinal follow-up using the PASS and underwent performance-based language testing and MRI scans that were processed for cortical thickness measures. We demonstrated a linear relationship between change in PASS Sum-of-Boxes and overall PPA-signature rate of atrophy (r = 0.3), with some patients progressing much more rapidly than others. Correlations were present between PASS fluency and WAB fluency (r = −0.92) and BDAE grammar (r = −0.94), PASS syntax/grammar and WAB fluency (r = −0.81) and BDAE grammar (r = −0.82), and PASS word comprehension and CSB word-picture matching (r = −0.87). The NACC UDS Global Language measure correlated with WAB fluency (r = −0.59) and BDAE grammar (r = −0.66) but not CSB. Inter-rater reliability (between neurologist and speech pathologist) of PASS ratings was high with ICC > 0.9 for fluency (0.99), grammar/syntax (0.99), word comprehension (0.91), and global CDR language (1.0). The PASS Sum-of-Boxes measure was more sensitive to the degree of clinical change than was the NACC UDS Global Language measure. These preliminary findings suggest that these novel clinical and imaging measures will likely cross-validate each other and demonstrate potential utility for clinical trials. The degree of impairment reflected by PASS scores was closely related to specific performance deficits, supporting the validity of the scale. The PASS Sum-of-Boxes measure was a more sensitive measure of clinical impairment and change over time than the existing global measure, supporting its value. Further work is in progress to assess the relationships between longitudinal change in PASS and longitudinal change in language test performance measures.

Performance-based testing for hydrogen leakage into passenger vehicle compartments

International regulatory representatives have proposed the performance-based test methodology for hydrogen fuel cell vehicle (HFCV) fuel system integrity certification in a new global technical regulation (GTR). For this test method, vehicle certification depends on system performance during barrier/rollover crash tests. The GTR proposal specifies that the test is failed if within 1 h post-crash, hydrogen leakage rates exceed 118 L/min or flammable mixtures develop within the passenger cabin or trunk. An analysis of the capabilities necessary to detect the second failure mode was performed through exploratory in-vehicle leakage tests at SRI International’s Corral Hallow Experimental Site. Hydrogen concentrations were primarily derived from oxygen depletion sensor measurements, and were compared to directly measured concentrations from co-located hydrogen sensors. Close agreement between the two sensor technologies was observed. Since oxygen depletion measurements have the additional advantage that nonflammable gases can be used, helium was investigated as a surrogate due to its similar diffusion and jet spreading characteristics. The good agreement in overall dispersion trends for both gases highlights the flexibility of the indirect sensor method. While hydrogen mixture fractions strongly depended on release characteristics (e.g., rate, location, type), the results of an analytic examination indicated that pinhole leaks from moderate source pressures likely would produce unacceptably high in-vehicle hydrogen concentrations. The optimum sensor location for leak detection was determined to be high above the release point. Accordingly, sensor placement for crash tests involving vehicle rollovers must account for the final vehicle orientation.