scholarly journals Step-by-Step Model with Latent Parameters for Student Assessments

2021 ◽  
Vol 3 (3) ◽  
pp. 188-198
Author(s):  
Vladimir Bratischenko
Keyword(s):  
Item Response ◽  
Statistical Processing ◽  
Ordinal Scale ◽  
Accurate Assessment ◽  
Test Results ◽  
Successful Completion ◽  
Statistical Procedures ◽  
Step Model ◽  
Student Assessments ◽  
Traditional Approaches

The article discusses the disadvantages of traditional approaches to statistical processing of assessments of intermediate attestations of students. We proposed a model in which the obtaining of the k grade on an ordinal scale is associated with the successful completion of k certification steps. By analogy with Item Response Theory used for processing test results the probability of a successful step is determined by latent parameters — the student's ability and the difficulty of the step. Methods for determining latent parameters from the estimates obtained and statistical procedures for checking the adequacy of the model are proposed. The data of processing the array of estimates are presented. The processing results confirmed the possibility of using the proposed mo­del for a more accurate assessment of students' ability and the difficulty of attestations.

scholarly journals Laboratory automation impact on antimicrobial resistance

2019 ◽  
Vol 40 (2) ◽  
pp. 66
Author(s):  
Patrick R Murray
Keyword(s):  
Fundamental Problem ◽  
Test Methods ◽  
Rapid Diagnosis ◽  
Laboratory Automation ◽  
Test Results ◽  
Clinical Value ◽  
Bacterial Cultures ◽  
Identification Of Bacteria ◽  
Diagnostic Microbiology ◽  
Traditional Approaches

Antibiotic resistance in common bacterial pathogens, such as Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae, has significantly limited the therapeutic options available for management of infectious diseases. While the indiscriminant use of broad spectrum antibiotics is a significant contributing factor, a more fundamental problem exists. Diagnostic microbiology test results have historically been available too late to be useful. This is, in part, due to the nature of the test methods and in part due to workflow practices in the laboratory. Thus, patients remain on empiric treatments that are frequently ineffective or unnecessarily too broad spectrum1,2. Microscopy and bacterial cultures are mainstays in the microbiology lab, using techniques developed more than 100 years ago. Although microbiologists speak with pride about the ‘art' of their science, the clinical value of the diagnostic tests is frequently lost because of the delays in reporting results with these ‘traditional' approaches. Fortunately, the practice of clinical microbiology is undergoing a dramatic transformation with the introduction of molecular diagnostics, primarily for rapid diagnosis of infections caused by viruses and difficult to grow bacteria, MALDI-TOF mass spectrometry for identification of bacteria, mycobacteria and fungi, and automation of all practices in bacteriology.

Understanding Diagnostic Test Results: Development of the Knowledge of Diagnostic Test Scale

2017 ◽  
Vol 61 (1) ◽  
pp. 661-665
Author(s):  
Katrina M. Ellis ◽  
Brittany Nelson
Keyword(s):  
Item Response ◽  
Diagnostic Test ◽  
Diagnostic Tests ◽  
Diagnostic Testing ◽  
Informed Decision Making ◽  
Test Results ◽  
Healthcare Settings ◽  
Medical Tests ◽  
Efficient Measure ◽  
New Instrument

As there are an increasing number of medical tests, it is even more important that patients understand the results from diagnostic tests in order to increase their probability of making accurate, informed decisions about their healthcare. The current paper outlines the development of the Knowledge of Diagnostic Test scale (KDT), a new instrument designed to measure the ability to understand the methodology of diagnostic testing and to apply diagnostic test results to accurate informed decision-making. Using Item Response Theory (IRT) in two studies, we investigated items to create an efficient measure of knowledge of diagnostic tests. Results suggested three items had desirable psychometric properties (i.e., of discriminability and difficulty) for measuring an average person’s diagnostic test knowledge. Implications for use in healthcare settings are briefly discussed.

scholarly journals The A-test: Assessment of functional recovery during early rehabilitation of patients in an orthopedic ward - content, criterion and construct validity

2014 ◽  
Vol 71 (8) ◽  
pp. 715-722 ◽  
Author(s):  
Aleksandra Vukomanovic ◽  
Aleksandar Djurovic ◽  
Zoran Popovic ◽  
Vesna Pejovic
Keyword(s):  
Hip Fracture ◽  
Construct Validity ◽  
Functional Recovery ◽  
Test Score ◽  
Weight Bearing ◽  
Hip Osteoarthritis ◽  
Early Rehabilitation ◽  
Ordinal Scale ◽  
Test Results ◽  
Orthopedic Ward

Background/Aim. The A-test was designed for assessment of functional recovery during early rehabilitation of patients in an orthopedic ward. This performance-based test consists of 10 items for assessing basic activities by a six level ordinal scale (0-5). Total scores can range from 0 to 50, i.e. from inability to perform any activity despite the help of therapists to complete independence and safety in performing all activities. The aim of this study was to examine the A-test validity. Methods. This prospective study was conducted in an orthopedic ward and included 120 patients [60 patients with hip osteoarthritis that underwent arthroplasty and 60 surgically treated patients with hip fracture (HF)] during early inpatient rehabilitation (1st-5th day). Validity was examined through 3 aspects: content validity - floor and ceiling effect, range, skewness; criterion validity - concurrent validity [correlation with the University of Iowa Level of Assistance Scale (ILAS) for patients with hip osteoarthritis, and with the Cumulated Ambulation Score (CAS) for patients with HF, Spearman rank correlation] and predictive validity [the New Mobility Score (NMS) 4 weeks after surgery, Mann-Whitney U test]; construct validity - 4 hypotheses: 1) on the fifth day of rehabilitation in patients underwent arthroplasty due to hip osteoarthritis, the A-test results will strongly correlate with those of ILAS, while the correlation with the Harris hip score will be less strong; 2) in patients with HF, the A-test results will be significantly better in those with allowed weight bearing as compared to patients whom weight bearing is not allowed while walking; 3) results of the A-test will be significantly better in patients with hip osetoarthritis than in those with HF; 4) the A-test results will be significantly better in patients younger than 65 years than in those aged 65 years and older. Results. The obtained results were: low floor (1%) and ceiling (2%) effect, range 0-50, skewness 0.57, strong correlation with ILAS for the patients with hip osteoarthritis (r = -0.97, p = 0.000) and with CAS for the patients with hip fracture (r = 0.91, p = 0.000) The patients with the A-test score 35 and more on the fifth day of rehabilitation (n = 46, Md = 4) had significantly higher NMS rank 4 weeks after surgery than the patients with the A-test score less than 35 (n = 59, Md = 2), (U = 379, z = -6.47, p = 0.000, r = 0.63). All 4 hypotheses were confirmed. Conclusion. The A-test is simple and valid instrument for everyday evaluation of pace and degree of functional recovery during early rehabilitation of patients surgically treated in an orthopedic ward.

MATHEMATICAL MODELLING OF FORECASTING THE RESULTS OF KNOWLEDGE TESTING / ŽINIŲ TIKRINIMO REZULTATŲ PROGNOZĖS MATEMATINIS MODELIAVIMAS

2008 ◽  
Vol 14 (3) ◽  
pp. 388-401 ◽  
Author(s):  
Aleksandras Krylovas ◽  
Natalja Kosareva
Keyword(s):  
Item Response ◽  
Logistic Model ◽  
Probability Distributions ◽  
Characteristic Functions ◽  
Test Results ◽  
Test Items ◽  
Mathematics Test ◽  
Level Method ◽  
Selection For ◽  
Selection Of

In this paper a mathematical model for obtaining probability distribution of the knowledge testing results is proposed. Differences and similarities of this model and Item Response Theory (IRT) logistic model are discussed. Probability distributions of 10 items test results for low, middle and high ability populations selecting characteristic functions of the various difficulty items combinations are obtained. Entropy function values for these items combinations are counted. These results enable to formulate recomendations for test items selection for various testing groups according to their attainment level. Method of selection of a suitable item characteristic function based on the Kolmogorov compatibility test, is proposed. This method is illustrated by applying it to a discreet mathematics test item. Santrauka Straipsnyje pasiūlytas matematinis modelis žinių tikrinimo rezultatų tikimybiniam skirstiniui gauti. Aptarti šio modelio ir užduočių sprendimo teorijos (IRT) logistinio modelio skirtumai ir panašumai. Išnagrinėti 10 klausimų testo rezultatų tikimybiniai skirstiniai silpnai, vidutinei ir stipriai testuojamųjų populiacijoms parenkant įvairias testo klausimų sunkumo funkcijų kombinacijas. Apskaičiuotos entropijos funkcijos reikšmės. Gauti rezultatai leidžia formuluoti rekomendacijas testo klausimams parinkti skirtingoms testuojamųjų grupėms pagal jų žinių lygį. Pasiūlytas tinkamiausios klausimo charakteristinės funkcijos parinkimo būdas, grindžiamas Kolmogorovo kriterijumi. Ši procedūra iliustruojama taikant ją konkrečiam diskrečiosios matematikos testo klausimui.

scholarly journals METHODOLOGY OF STATISTICAL PROCESSING OF KNOWLEDGE TESTING RESULTS

2021 ◽  
Vol 1 (1) ◽  
pp. 363-364
Author(s):  
Aleksey Bal'chugov
Keyword(s):  
Statistical Processing ◽  
Critical Value ◽  
Test Results

It is proposed to use a criterion similar to Cochran's criterion for statistical pro cessing of test results. It is shown that the critical value of the Cochran criterion for a group of 4 people who have been tested on 5 topics is approximately 0.2.

scholarly journals CORRECTION OF HYPODINAMY AS A FACTOR OF THE RISK OF OBESITY DEVELOPMENT IN FIRE-RESCUERS

2018 ◽  
Vol 25 (3) ◽  
pp. 40-45
Author(s):  
E. V. BURDYUKOVA ◽  
A. N. ARKHANGELSKAYA ◽  
S. N. ALEKSEENKO ◽  
I. A. YAKIREVICH ◽  
E. A. DMITRIEVA ◽  
...  
Keyword(s):  
High Efficiency ◽  
Statistical Processing ◽  
Main Group ◽  
The Body ◽  
Control Group ◽  
Test Results ◽  
Food Label ◽  
Development Indicators ◽  
History Of ◽  
In Fire

Aim. To evaluate the effectiveness of the developed special sports complex in the prevention of hypodynamia and obesity among firefighters-rescuers.Materials and methods. A survey of 490 men with no history of chronic infectious and non-infectious diseases aged 20-59 was conducted. 328 people were the main group, 162 people were the control group. The baseline data included anthropometric development indicators, bioimpedance test results, the extraction of biochemical blood test results; the body mass index (BMI) and the ratio of waist and hip circumference were determined. A questionnaire was conducted to identify hypodynamia (according to the IPAQ questionnaire) and the nutrition structure (according to the questionnaire on the food label literacy questionnaire, past). Both questionnaires were adapted to the Russian Federation. Statistica for Windows 8.0 was used for statistical processing. We used a comparison of the means of the Student method. To compare the values expressed in percent, the method of inverse trigonometric Fisher transformations was used.Results. We have developed and proposed for firefighters-rescuers, included in the main group, special sports complexes, which were used for 6 months. These complexes represent additional physical training by the developed method. There are two of them: one with an emphasis on the prevention and rehabilitation of people with osteochondrosis of the lumbar spine, and the other for cervical and thoracic localization, including with a syndrome of shoulder-scapular periarthritis.Classes were held 3 times a week, the duration of 1 session was 45-50 minutes. The choice of the complex was carried out at the request of firefighters-rescuers. The first complex was selected by 52 people. Based on the results of the study, against the background of the use of sports complexes, there was a 2-fold decrease in the incidence of obesity. Such a high efficiency is due to the fact that obesity of the I degree prevailed among the firefighters-rescuers. In addition, the frequency of occurrence of dyslipidemia, hyperglycemia, and hypodynamia decreased.Conclusion. The use of this sports complex can reduce the risk factors for development of disability among rescue firefighters by preventing hypodynamia and reducing the incidence of hyperglycemia and dyslipidemia, as factors in the development of obesity.

scholarly journals An Application of Item Response Theory to Scoring Patient Safety Culture Survey Data

2020 ◽  
Vol 17 (3) ◽  
pp. 854
Author(s):  
Heon-Jae Jeong ◽  
Hsun-Hsiang Liao ◽  
Su Ha Han ◽  
Wui-Chiang Lee
Keyword(s):  
Patient Safety ◽  
Item Response Theory ◽  
Item Response ◽  
Safety Culture ◽  
Patient Safety Culture ◽  
Ordinal Scale ◽  
Response Theory ◽  
Scoring Method ◽  
The Mean ◽  
Domain Scores

Patient safety culture is important in preventing medical errors. Thus, many instruments have been developed to measure it. Yet, few studies focus on the data processing step. This study, by analyzing the Chinese version of the Safety Attitudes Questionnaire dataset that contained 37,163 questionnaires collected in Taiwan, found critical issues related to the currently used mean scoring method: The instrument, like other popular ones, uses a 5-point Likert scale, and because it is an ordinal scale, the mean scores cannot be calculated. Instead, Item Response Theory (IRT) was applied. The construct validity was satisfactory and the item properties of the instrument were estimated from confirmatory factor analysis. The IRT-based domain scores and mean domain scores of each respondent were estimated and compared. As for resolution, the mean approach yielded only around 20 unique values on a 0 to 100 scale for each domain; the IRT method yielded at least 440 unique values. Meanwhile, IRT scores ranged widely at each unique mean score, meaning that the precision of the mean approach was less reliable. The theoretical soundness and empirical strength of IRT suggest that healthcare institutions should adopt IRT as a new scoring method, which is the core step of processing collected data.

A Hybrid Approach to Content-Based Image Retrieval

2013 ◽  
pp. 91-104
Author(s):  
Görkem Asilioglu ◽  
Emine Merve Kaya ◽  
Duygu Sarikaya ◽  
Shang Gao ◽  
Tansel Ozyer ◽  
...  
Keyword(s):  
Hybrid Approach ◽  
Input Image ◽  
Image Features ◽  
Content Based Image Retrieval ◽  
Test Results ◽  
Image Storage ◽  
Storage And Retrieval ◽  
Image Storage And Retrieval ◽  
Traditional Approaches ◽  
Distance Sets

Digital image storage and retrieval is gaining more popularity due to the rapidly advancing technology and the large number of vital applications, in addition to flexibility in managing personal collections of images. Traditional approaches employ keyword based indexing which is not very effective. Content based methods are more attractive though challenging and require considerable effort for automated feature extraction. In this chapter, we present a hybrid method for extracting features from images using a combination of already established methods, allowing them to be compared to a given input image as seen in other query-by-example methods. First, the image features are calculated using Edge Orientation Autocorrelograms and Color Correlograms. Then, distances of the images to the original image will be calculated using the L1 distance feature separately for both features. The distance sets will then be merged according to a weight supplied by the user. The reported test results demonstrate the applicability and effectiveness of the proposed approach.

scholarly journals An Improved Incidence Losses Prediction Method for Turbine Airfoils

1989 ◽  
Author(s):  
S. H. Moustapha ◽  
S. C. Kacker ◽  
B. Tremblay
Keyword(s):  
Aspect Ratio ◽  
Prediction Method ◽  
Leading Edge ◽  
Prediction Methods ◽  
Accurate Assessment ◽  
Test Results ◽  
Periodic Review ◽  
Empirical Correlations ◽  
Axial Turbines ◽  
Turbine Airfoils

The off-design performance of axial turbines is usually predicted by calculating the incidence losses using empirical correlations. Periodic review and improvement to these prediction methods, to reflect recent turbine designs and test results, are essential for the accurate assessment of losses in turbine airfoils. The purpose of the present work is to evaluate existing turbine incidence loss correlations, and present an improved prediction method for profile and secondary losses at off-design conditions which correlates better with the available experimental results. The incidence losses are shown to be a function of leading edge diameter, pitch, aspect ratio and channel convergence.

Desirable standards for laboratory tests if they are to fulfill medical needs

1993 ◽  
Vol 39 (7) ◽  
pp. 1447-1455 ◽  
Author(s):  
C G Fraser ◽  
P H Petersen
Keyword(s):  
Laboratory Tests ◽  
Normal Values ◽  
Performance Standards ◽  
Biological Variation ◽  
Test Results ◽  
Medical Needs ◽  
Advantages And Disadvantages ◽  
Clinical Vignettes ◽  
Traditional Approaches ◽  
Test Result

Abstract Many strategies to define desirable standards for laboratory tests to fulfill medical needs have been proposed over the last three decades. Traditional approaches are based on reference (normal) values, opinions of clinicians, the state of the art, views of experts, data on biological variation, and assessment of the effect of error on clinical use. All these approaches have advantages and disadvantages, but the consensus of experts reached over a decade ago that imprecision desirably be less than one-half of the within-subject biological variation still seems to provide the best set of generally applicable performance standards. Desirable bias is less than one-quarter of the group (within-subject plus between-subject) biological variation. Recent proposals are either restatements of traditional recommendations, further empirical suggestions, or models based on assessment of clinical needs, and have not been widely accepted. Both old and new studies on clinical opinions, sought by using structured questionnaires containing clinical vignettes designed to seek views on the magnitude of significant change, are flawed in design, execution, and data analysis. Until clinicians are more aware of test-result variability and clinical chemists gain quantitative knowledge on the interpretation of test results, it will be difficult to set desirable standards that fulfill actual medical needs, except in a few well-defined screening situations.

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