Minimum Acceptable Performance Research Articles

Acceptable performance of blood biomarker tests of amyloid pathology - recommendations from the Global CEO Initiative on Alzheimer's Disease.

Anti-amyloid treatments for early symptomatic Alzheimer disease have recently become clinically available in some countries, which has greatly increased the need for biomarker confirmation of amyloid pathology. Blood biomarker (BBM) tests for amyloid pathology are more acceptable, accessible and scalable than amyloid PET or cerebrospinal fluid (CSF) tests, but have highly variable levels of performance. The Global CEO Initiative on Alzheimer's Disease convened a BBM Workgroup to consider the minimum acceptable performance of BBM tests for clinical use. Amyloid PET status was identified as the reference standard. For use as a triaging test before subsequent confirmatory tests such as amyloid PET or CSF tests, the BBM Workgroup recommends that a BBM test has a sensitivity of ≥90% with a specificity of ≥85% in primary care and ≥75-85% in secondary care depending on the availability of follow-up testing. For use as a confirmatory test without follow-up tests, a BBM test should have performance equivalent to that of CSF tests - a sensitivity and specificity of ~90%. Importantly, the predictive values of all biomarker tests vary according to the pre-test probability of amyloid pathology and must be interpreted in the complete clinical context. Use of BBM tests that meet these performance standards could enable more people to receive an accurate and timely Alzheimer disease diagnosis and potentially benefit from new treatments.

Optimizing upside variability and antifragility in renewable energy system design

Despite the considerable uncertainty in predicting critical parameters of renewable energy systems, the uncertainty during system design is often marginally addressed and consistently underestimated. Therefore, the resulting designs are fragile, with suboptimal performances when reality deviates significantly from the predicted scenarios. To address this limitation, we propose an antifragile design optimization framework that redefines the indicator to optimize variability and introduces an antifragility indicator. The variability is optimized by favoring upside potential and providing downside protection towards a minimum acceptable performance, while the skewness indicates (anti)fragility. An antifragile design primarily enhances positive outcomes when the uncertainty of the random environment exceeds initial estimations. Hence, it circumvents the issue of underestimating the uncertainty in the operating environment. We applied the methodology to the design of a wind turbine for a community, considering the Levelized Cost Of Electricity (LCOE) as the quantity of interest. The design with optimized variability proves beneficial in 81% of the possible scenarios when compared to the conventional robust design. The antifragile design flourishes (LCOE drops by up to 120%) when the real-world uncertainty is higher than initially estimated in this paper. In conclusion, the framework provides a valid metric for optimizing the variability and detects promising antifragile design alternatives.

Predicting Pavement Condition Index Using Machine Learning Algorithms and Conventional Techniques

Government agencies and transportation engineers use pavement management systems (PMS) to evaluate pavement performance and keep pavement above the minimum acceptable performance standards. The Pavement Condition Index (PCI) and the international roughness index (IRI) are among the most commonly used indices to evaluate pavement conditions. Due to IRI data collection being more accessible and less expensive than collecting pavement distress data, this study aims to develop PCI models that can successfully estimate the PCI values based on IRI for flexible pavement using two Machine Learning techniques (ML), namely: Random Forest (RF), and Support Vector Machine (SVM), and three conventional techniques, namely: linear, quadratic, and cubic regression. The study was carried out with the database collected from the Long-Term Pavement Performance (LTPP) program. The results of the dataset reveal that both ML models (RF and SVM) have strong prediction ability with high values of coefficient of determination (R^2 = 99.7 and 96.8) %, and low values of Root Mean Squared Error (RMSE = 1.095 and 3.569) % and Mean Absolute Error (MAE = 0.474 and 2.244). In conclusion, the goodness of fit of the proposed ML models was compared with conventional techniques models previously developed. The results showed that the ML models yielded higher prediction accuracy than conventional techniques.

Impact of the academic performance grades on the blood picture in female students

The paper presents the blood picture patterns in female students with different average academic performance grades in their record book. An improvement in the academic performance of female students is accompanied by a significant decrease in the concentration of neutrophils, a significant increase in the level of lymphocytes and minor changes in other blood parameters. Thus, the level of neutrophils experiences a gradual decrease, reaching its minimum of 57.7% (P <0.02) in girls who has performance grade A and 66.2 in case of grade C. The number of lymphocytes in girls with the highest academic performance grades in the record book is recorded to be 33.6% (P <0.05), while in those with the minimum acceptable performance grade it is found to be 26.1%. The level of platelets increases up to 320.8 thousand per microliter (mcL) of blood in the girls with academic performance grade B, decreases to 296.4 in case of grade A, and it is reported to reach 287.0 for those with academic performance grade C.

Development of physical employment standards of specialist paramedic roles in the National Ambulance Resilience Unit (Naru)

AimTo develop evidence-based role-specific physical employment standards and tests for National Ambulance Resilience Unit (NARU) specialist paramedics. MethodsSixty-two (53 men, 9 women) paramedics performed an array of (1) realistic reconstructions of critical job-tasks (criterion job performance); (2) simplified, easily-replicable simulations of those reconstructions and; (3) fitness tests that are portable and/or practicable to administer with limited resources or specialist equipment. Pearson's correlations and ordinary least products regression were used to assess relationships between tasks and tests. Performance on reconstructions, subject-matter expert and participant ratings were combined to derive minimum acceptable job performance levels, which were used to determine cut-scores on appropriate correlated simulations and tests. ResultsThe majority of performance times were highly correlated with their respective simulations (range of r: 0.73–0.90), with the exception of those replicating water rescue (r range: 0.28–0.47). Regression compatibility intervals provided three cut-scores for each job-task on an appropriate simulation and fitness test. ConclusionThis study provides a varied and easily-implementable physical capability assessment for NARU personnel, empirically linked to job performance, with flexible options depending on organisational requirements.

Reliability-based assessment and calibration of standards for the lateral vibration of pedestrian bridges

Ensuring vibrations remain tolerable to occupants is central to the serviceability limit state (SLS) design of lightweight pedestrian bridges. In general, pedestrians tend to be more sensitive to lateral bridge vibrations compared to vertical vibrations, which underscores the importance of serviceability limit state (SLS) design in the lateral direction. Significant uncertainties associated with the pedestrian loading and bridge behaviour motivate the need to treat serviceability design provisions from a reliability standpoint. This paper is a first attempt towards such an assessment and code calibration of SLS provisions applicable to the lateral direction in the existing major pedestrian bridge design guidelines (ISO 10137, Eurocode 5 and SÉTRA). For this purpose, this study adopts a reliability-based framework, which accounts for the uncertainties arising from the pedestrian loading, perceptions of vibration by pedestrians, and structural damping. Furthermore, SLS design generally considers commonly occurring design traffic densities only. However, several historical lateral vibration serviceability failures of pedestrian bridges have occurred under infrequent loading events. Hence, this paper also incorporates infrequent traffic event (load case) in the reliability assessment and calibration of the design guidelines. Results show that metal truss-type pedestrian bridges under design and infrequent traffic events need to be designed to a higher reliability level (through calibration) than currently achieved by these provisions under the design event. Adopting traffic density and frequency-dependent acceleration limits can mitigate overdesigns resulting from the calibration exercise. The desired reliability index required to achieve minimum acceptable performance of the designs under both the design and infrequent events is estimated iteratively in the proposed procedure, followed by the calculation of design calibration factors. This study shows that the calibration of some design provisions (e.g., SÉTRA) depends on amplitude-dependent damping values, while this is not the case with other provisions. This dependency can be attributed to differences in the form of the limit state function. Finally, it is shown that the proposed calibration process achieves sufficient and consistent reliability across all bridge classes under design and infrequent traffic events in the lateral direction, while ensuring economic designs using traffic density and frequency-based comfort limits.

Assessment of Skill and Competence in Dental Education I: Control Lists and Rubrics

Diş hekimliği eğitiminin hedefi; mezunların güvenli, etkili ve bağımsız uygulamaları yapabilme seviyesine ulaşmalarına yardımcı olmaktır. Bu düzeydeki yeterlik; mezuniyet için gerekli minimum performans seviyesindeki akademik bilgi, klinik beceri ve profesyonel davranışların kazanımını gerektirir. Diş hekimliği eğitimindeki beceri kavramı; mesleki becerileri akla getirir. Bununla birlikte, diş hekimliği gibi meslekler için öğrencilerin sadece klinik olarak yetkin olmakla kalmayıp, topluma iyi hizmet verebilmek için iyi uyum becerilerine de sahip olmaları beklenir. Performans kontrol listeleri ve ölçekler öğrencilerin becerilerinin ölçülmesinde kullanılan araçlardır. Çok iyi bilindiği gibi, “değerlendirme öğrenimi yönlendirir” ve öğrenimin şeklini ve içeriğini programlar. Bu derleme çalışmasında, ölçme ve değerlendirme yöntemleri; kontrol listeleri ve ölçeklerin hazırlığı, kullanımı ve doğru ölçme aracının tercihi konusunda bilgi verilerek, diş hekimliği öğrencilerinin yeterlik ve becerilerinin ölçülmesinde kullanılan güncel uygulamalar konusunda farkındalık oluşturulmaktadır.

Nurse anesthetists' preferences for anesthesiologists' participation in patient care at a large teaching hospital

Study objectiveCertified registered nurse anesthetists (CRNAs) can evaluate anesthesiologists with whom they work clinically using a psychometrically reliable and valid scale. Use of such a scale to evaluate performance depends on knowing thresholds for minimum and ideal anesthesiologist performance. DesignCohort study. SettingOne large teaching hospital. Measurements379 CRNA evaluations of anesthesiologists' performance, and associated thresholds for minimum and ideal scores, performed over 15 weeks. Main resultsThe anesthesiologists' performance score was less than the CRNA's minimum score for the evaluation (i.e., too little anesthesiologist participation in patient care) for 25% (95) of the CRNA evaluations. The score was greater than the CRNA's ideal score for the evaluation (i.e., excessive participation in patient care) for 28% (106) of evaluations. Anesthesiologists' performance was assessed as not meeting expectations 53% of the time. Even if every anesthesiologist performed consistently at the same level, ≥50% of CRNAs would have been dissatisfied (187), not significantly different from observed (P = 0.34).Consistent results were found when the unit of analysis was individual CRNA. Among the 22 CRNAs who provided ≥10 evaluations, the median level of anesthesiologist performance was either less than the individual CRNA's mean minimum acceptable performance (8/22) or greater than their mean ideal performance (9/22), with overall dissatisfaction, 77%.Among the CRNA-anesthesiologist pairs working together, most did so less than once per month (76%, 1242/1635). ConclusionsIn this single-center study at a large teaching hospital, broad heterogeneity among CRNAs in their expectations for anesthesiologist collaborative practice was found. Anesthesiologists adjusting their behavior based on individual CRNA preferences was impractical because specific CRNA-anesthesiologist pairs work together infrequently. Future studies should examine consistency among organizations and whether changes in expectations, and perhaps less dissatisfaction, can be achieved by communication of results for CRNA preferences for anesthesiologists' participation in patient care and discussing shared expectations among the CRNAs and anesthesiologists.

Angoff anchor statements: setting a flawed gold standard?

This article was migrated. The article was marked as recommended. The Angoff standard setting method depends fundamentally on the conceptualisation of an anchor statement. The precise wording and consequent interpretation of anchor statements varies in practice. Emphasis is often placed on standard setting judges' perceptions of difficulty for a candidate subgroup. The current review focusses on the meaning of anchor statements and argues that when determining the required standard of performance it is more appropriate to consider: (1) what it is important to achieve, and not how difficult it is to achieve it; (2) what all candidates should achieve, and not what a subgroup of candidates would achieve. In summary, current practice should be refined by using an anchor statement which refers to estimating the 'minimum acceptable performance by every candidate' for each item being tested, and then requiring each judge to score the relevant aspects of importance which could then be combined to derive a cut-score.

Physical Employment Standards for UK Firefighters: Minimum Muscular Strength and Endurance Requirements.

Objective:The aim of this study was to assess sensitivity and specificity of surrogate physical ability tests as predictors of criterion firefighting task performance and to identify corresponding minimum muscular strength and endurance standards.Methods:Fifty-one (26 male; 25 female) participants completed three criterion tasks (ladder lift, ladder lower, ladder extension) and three corresponding surrogate tests [one-repetition maximum (1RM) seated shoulder press; 1RM seated rope pull-down; repeated 28 kg seated rope pull-down]. Surrogate test standards were calculated that best identified individuals who passed (sensitivity; true positives) and failed (specificity; true negatives) criterion tasks.Results:Best sensitivity/specificity achieved were 1.00/1.00 for a 35 kg seated shoulder press, 0.79/0.92 for a 60 kg rope pull-down, and 0.83/0.93 for 23 repetitions of the 28 kg rope pull-down.Conclusions:These standards represent performance on surrogate tests commensurate with minimum acceptable performance of essential strength-based occupational tasks in UK firefighters.

Compliance of Iranian perfusionist with the American Society of extracorporeal technology standards

Background: Standards play an important role in representing the minimum favorable and acceptable performance and are used in determining the exact current status of a hospital and evaluating and monitoring its performances. Standards also play an important role in providing quality services by perfusionists to patients undergoing open heart surgery with heart–lung machine. Objectives: This study aimed to analyze the compliance with standards related to perfusionists in Iran by comparison with the American Society of Extracorporeal Technology Standards. Methods: In this descriptive cross-sectional study, a questionnaire developed by the American Society of Extracorporeal Technology Standards was used to collect data from 48 Iranian hospitals and educational medical centers. The level of compliance with perfusion standards related to perfusionists was analyzed and compared with the American Society of Extracorporeal Technology Standards. Results: The results showed that 45.52% of the centers were in compliance with factors related to standards of competence, qualification, and backup staffing for critical situation. Only 23% of the centers comply with standards of perfusionists' interaction with the medical team which indicates an unsatisfactory interaction between perfusionists and the medical team, and regarding the working hours, only 18.5% of the centers comply with the standards in this area. Conclusion: The comparison made between the compliance of Iranian perfusionists and the American Society of Extracorporeal Technology Standards reveals an unsatisfactory level. This suggests the need for the development of accreditation programs and standards of care on the one hand and conduction of a continuous evaluation of these standards on the other hand.

A Task Analysis Methodology for the Development of Minimum Physical Employment Standards.

The aim of this study was to develop a systematic task analysis process for determination of minimum acceptable job performance in arduous safety-related occupations. A task analysis using modifications on established methods was completed in UK firefighters. Subject-matter experts (all male) identified critical, physically arduous tasks generic to all UK firefighters and developed individual, role-specific task simulations. Video footage and blinded voting were used to determine minimum acceptable task performance. Eight tasks were identified in combination with role-specific variations, task simulations suitable for use in a physical demands analysis, and corresponding minimum acceptable performance. The bespoke steps highlighted here allow structured identification of task-specific minimum performance standards and simulations from which physical employment standards could be based. However, including a more divergent expert panel with respect to age, sex, and race would strengthen the applicability of this framework in future practice.

Application of Sigma Metrics Analysis for the Assessment and Modification of Quality Control Program in the Clinical Chemistry Laboratory of a Tertiary Care Hospital.

Sigma is a metric that quantifies the performance of a process as a rate of Defects-Per-Million opportunities. In clinical laboratories, sigma metric analysis is used to assess the performance of laboratory process system. Sigma metric is also used as a quality management strategy for a laboratory process to improve the quality by addressing the errors after identification. The aim of this study is to evaluate the errors in quality control of analytical phase of laboratory system by sigma metric. For this purpose sigma metric analysis was done for analytes using the internal and external quality control as quality indicators. Results of sigma metric analysis were used to identify the gaps and need for modification in the strategy of laboratory quality control procedure. Sigma metric was calculated for quality control program of ten clinical chemistry analytes including glucose, chloride, cholesterol, triglyceride, HDL, albumin, direct bilirubin, total bilirubin, protein and creatinine, at two control levels. To calculate the sigma metric imprecision and bias was calculated with internal and external quality control data, respectively. The minimum acceptable performance was considered as 3 sigma. Westgard sigma rules were applied to customize the quality control procedure. Sigma level was found acceptable (≥3) for glucose (L2), cholesterol, triglyceride, HDL, direct bilirubin and creatinine at both levels of control. For rest of the analytes sigma metric was found <3. The lowest value for sigma was found for chloride (1.1) at L2. The highest value of sigma was found for creatinine (10.1) at L3. HDL was found with the highest sigma values at both control levels (8.8 and 8.0 at L2 and L3, respectively). We conclude that analytes with the sigma value <3 are required strict monitoring and modification in quality control procedure. In this study application of sigma rules provided us the practical solution for improved and focused design of QC procedure.

Development of role-related minimum cardiorespiratory fitness standards for firefighters and commanders

A minimum cardiorespiratory fitness standard was derived for firefighters following a metabolic demands analysis. Design and minimal acceptable performance of generic firefighting task simulations (i.e. hose running, casualty evacuation, stair climb, equipment carry, wild-land fire) were endorsed by a panel of operationally experienced experts. Sixty-two UK firefighters completed these tasks wearing a standard protective firefighting ensemble while being monitored for peak steady-state metabolic demand and cardiovascular strain. Four tasks, endorsed as valid operational simulations by ≥90% of participants (excluding wild-land fire; 84%), were deemed to be a sufficiently valid and reliable basis for a fitness standard. These tasks elicited an average peak steady-state metabolic cost of 38.1 ± 7.8 ml kg−1 min−1. It is estimated that healthy adults can sustain the total duration of these tasks (~16 min) at ≤90% maximum oxygen uptake and a cardiorespiratory fitness standard of ≥42.3 ml kg−1 min−1 would be required to sustain work.Practitioner Summary: A cardiorespiratory fitness standard for firefighters of ≥42.3 ml kg−1 min−1 was derived from monitoring minimum acceptable performance of essential tasks. This study supports the implementation of a routine assessment of this fitness standard for all UK operational firefighters, to ensure safe physical preparedness for occupational performance.

Physiological employment standards I. Occupational fitness standards: objectively subjective?

This paper examines the processes involved in the establishment of a minimum occupational fitness standard, with particular reference to the interplay that inevitably occurs between objective measurements and subjective decisions. The areas considered include: the determination of the critical task on which to base a standard; establishing minimum acceptable performance and methods of best practice for the execution of these tasks; determining the physical demands of a task and a reasonable relative workload; producing the final standard. Finally, the impact of the subjective component of the development of an occupational fitness standard on its defensibility is discussed. It is concluded that all standards involve some subjective aspects; the extent of these could be reduced by further research. In the meantime, it would be prudent for those developing standards to detail the rationale, methods and evidence by which subjective decisions were reached, to provide an audit trail for subsequent investigation.

IRIS Recognition Based On LBP and Combined LVQ Classifier

Iris recognition is considered as one of the best biometric methods used for human identification and verification, this is because of its unique features that differ from one person to another, and its importance in the security field. This paper proposes an algorithm for iris recognition and classification using a system based on Local Binary Pattern and histogram properties as a statistical approaches for feature extraction, and Combined Learning Vector Quantization Classifier as Neural Network approach for classification, in order to build a hybrid model depends on both features. The localization and segmentation techniques are presented using both Canny edge detection and Hough Circular Transform in order to isolate an iris from the whole eye image and for noise detection .Feature vectors results from LBP is applied to a Combined LVQ classifier with different classes to determine the minimum acceptable performance, and the result is based on majority voting among several LVQ classifier. Different iris datasets CASIA, MMU1, MMU2, and LEI with different extensions and size are presented. Since LBP is working on a grayscale level so colored iris images should be transformed into a grayscale level. The proposed system gives a high recognition rate 99.87 % on different iris datasets compared with other methods.

Tacit Knowledge: A Needed Addition to SOPs in a Forensic Science Environment

Abstract Within a quality management structure at a forensic science organization where processes are explicit by nature, the authors have found that there is still a tacit element required, where a baseline of minimum acceptable performance from protocols is supplemented by interactions with colleagues and one's own thought processes. Such concepts are only being discussed at a nascent level in the Quality Management System literature, where the tacit world has not yet diffused into the very explicit world found in quality management writings. In looking at the process level, findings are presented with respect to the interplay of the explicit knowledge within standard operating procedures and the practitioners' tacit knowledge requirements needed in actually completing the process. Ultimately, these findings will help improve the way process is carried out in a knowledge-intensive forensic science environment by having insights into how tacit knowledge works, and make conclusions on tacit knowledge with...

The prediction of building performance during earthquakes

Procedures for the seismic design of new buildings to achieve a minimum acceptable performance are well established. However, it is concluded in this paper that the actual performance of structures will not be predicted with any certainty using the same procedures, given the uncertainties associated with the assumptions that must be made. Sole reliance on design procedures to predict performance is likely to lead to unnecessary conservatism and this must be taken into account when setting standards for design.&#x0D; It is also concluded that there is currently insufficient data available in a suitable form to enable the correlation between analysis and actual performance to be assessed in any way other than by judgement.&#x0D; The prediction of seismic performance remains very much an art.

Field normalization techniques and practices for determining sound isolation and impact insulation

The International Building Code (IBC) includes minimum acceptable acoustical performance for floor/ceiling assemblies separating dwelling units. Field tests for determining the Normalized Noise Isolation Class (NNIC) and Field Impact Insulation Class (FIIC) of an assembly require the measurement of the decay rate of the receiving room and the normalization of the sound pressure levels, as set forth in ASTM standards E336 and E1007. The normalization is intended to improve comparability of test results by removing the effects of receiving room absorption. Surprisingly, the normalization procedure is substantially different between these two types of tests. The FIIC normalization is based on the laboratory Impact Insulation Class (IIC) test using a standard room absorption of 10 metric sabins. The NNIC normalization is based on a 0.5-s reverberation time, which is assumed normal in a furnished habitable dwelling space. This difference in normalization procedure for the same receiving room potentially yields different results of NNIC and FIIC as compared with their respective non-normalized values. This will be illustrated with examples of actual field tests. The effectiveness and suitability of the normalization procedures in the field setting are compared and evaluated including the use of the California Building Code modification to FIIC.

Stress Relaxation Testing of Service Exposed IN738 for Creep Strength Evaluation

Standard size and miniature specimens of IN738 were taken from a service exposed turbine blade and vane for comparative stress relaxation testing at 800C, 850C, and 900C. Base data taken from root section material were used to construct stress versus creep rate parametric curves which could be used directly in design. Up to five decades in creep rates were obtained at each temperature from tests lasting less than one day. The data were also presented in the form of stress versus predicted times to 0.5 percent creep which compared well with available long time creep data. Differences were noted in specimens taken from different locations in the airfoil regions which probably resulted from differences in grain size or orientation. Based on these measurements it was concluded that there was no significant effect of section size on creep strength as defined by this test, and that the alloy was quite insensitive to prior deformation and thermal exposures. A life management procedure, using a combination of creep strength evaluation based on the stress relaxation test and a separate fracture evaluation measurement, is outlined in which end of useful life is defined in terms of minimum acceptable performance levels. [S0742-4795(00)01803-2]