Reliable Measure Research Articles

Abstract 7453: Psychometric analysis of Neuro-QoL Perceived Cognitive Function tool in primary brain tumor patients

Abstract Cognitive dysfunction is commonly reported but variable in course and severity in the primary brain tumor (PBT) population. Brief, reliable, and sensitive measures of patient-reported outcomes (PRO) of cognitive symptoms on function are needed for clinical care and research. This study aims to assess the reliability and validity of the Neuro-QoL Perceived Cognitive Function tool (NQC) and explore associations with symptoms and objective testing of cognitive dysfunction in a cohort of PBT patients enrolled in a natural history study (NCT02851706: PI T. Armstrong). Patient sample characteristics and PROs, including NQC (<40 = moderate/severe (MS) dysfunction), a symptom burden measure (MD Anderson Symptom Inventory-Brain Tumor (MDASI-BT), scores ≥5 = MS) and the Montreal Cognitive Assessment ((MoCA), scores ≤ 25 indicating cognitive impairment (range: 0-30)) were collected. Descriptive statistics and a psychometric analysis consisting of bivariate correlations, Cronbach’s alpha, and factor analyses using principal axis factoring with nonorthogonal rotation were performed. Cohen’s kappa and correlation were used to assess agreement between objective and subjective measures of cognitive function. The cohort included 327 patients who completed the NQC at study entry [median age: 47 years (range: 18-85), primarily white (78%) males (55%) with high-grade tumors (73%), 65% with a Karnofsky Performance Status (KPS) ≥ 90 (good), and 29% reporting MS cognitive dysfunction]. Factor analysis of the NQC identified two underlying factor groupings: concentration/focus and executive function with Cronbach’s alphas of 0.92 and 0.91 that are interpretable and provided adequate fit for the data. While the NQC was moderately correlated with several MDASI-BT symptom factors, it was highly associated with the cognitive factor (r = -.646). To assess agreement, a subset of patients also completed the MoCA (n=172). These were primarily male (58%), white (79%), had high-grade tumors (67%), and a good KPS score (67%). In this subset, 24% had MS cognitive dysfunction as measured by the NQC while 44% were cognitively impaired using the MoCA resulting in a kappa agreement of 0.07. The correlation between the MoCA score and NQC T-score was -0.292. Understanding the impact and prevalence of cognitive symptoms, objective cognitive testing, and perceived impact is essential for PBT patient care and identifying supportive care interventions. Select NQC psychometric properties demonstrate reliability and validity in this population, with strong agreement with self-report of cognitive symptoms but weaker correlation with objective testing, highlighting the variability in perceived impact. Future research in cognitive function will explore the use of objective testing and perceived impact, its predictors in select populations (i.e., IDH-mutant tumors), and examine its association with biomarkers. Citation Format: Morgan L. Johnson, Elizabeth Vera, Kimberly Reinhart, Hope Miller, Anna Choi, Tricia Kunst, Bennett McIver, Ewa Grajkowska, Michelle L. Wright, Terri S. Armstrong, Tito Mendoza. Psychometric analysis of Neuro-QoL Perceived Cognitive Function tool in primary brain tumor patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7453.

Examining Peer Observation Practices of Online Teaching and Learning Through Analysis of Existing Instruments

ABSTRACT As online teaching gains increasing popularity in higher education, the need for valid and reliable measures to assess course quality and instructional effectiveness has become paramount. Peer observation of teaching has served as a valuable tool in evaluating online courses and facilitating continuous improvement. This study is intended to identify and analyze existing peer observation instruments used in higher education institutions in the U.S. specifically focusing on R1 and R2 institutions according to the Carnegie classification. Using the Online Teaching Competencies (OTC) framework developed by Farmer and Ramsdale (2016) as a coding basis, a total of 34 instruments were collected and examined. Coding results based on OTC revealed three highly observed competencies, including a prevalent emphasis on alignment between course activities and learning objectives, instructor availability for learners, and the provision of clear and consistent instructions. However, a substantial number of competencies in the OTC framework were never utilized by any of the collected instruments. Likewise, a large number of competencies measured by the collected instruments were not included in the OTC framework, suggesting potential gaps in the evaluation of course design and accessibility for students with disabilities. This study offers insight into the current state of peer observation practices for online teaching and highlights areas for improvement and refinement of evaluation frameworks.

The revised Psychosis Attachment Measure: further psychometric evidence.

Disorganised attachment is a key concept in understanding the development of psychosis. However, existing questionnaires of adult attachment do not adequately measure this construct hindering future research into the psychosocial causes of psychosis. The most widely measure of adult attachment in people experiencing psychosis is the Psychosis Attachment Measure (PAM). The measure has recently been revised to include disorganised attachment items. This study develops previous research by providing a rigorous examination the psychometric properties of the revised questionnaire (PAM-R). A total of 407 participants with self-reported experiences of psychosis completed a battery of questionnaires which included the PAM-R and other measures which were conceptually related to the concept of disorganised attachment. Confirmatory factor analysis (CFA) indicated a three-factor solution with factors corresponding to anxious, avoidant, and disorganised attachment. The majority of the fit statistics were acceptable with the exception of the RMSEA statistic. Internal consistency and test-retest reliability were good for all subscales. The disorganised subscale correlated in expected directions with other measures of attachment, dissociation, trauma, and psychotic experiences. The PAM-R is a valid and reliable measure of adult attachment. It is a practical assessment tool for clinicians and researchers to measure insecure and disorganised attachment patterns that is acceptable to people experiencing psychosis.

Reliability and validity of the responsive care tool for children 0–3 years old in a rural, South Asian setting

Research has shown the importance of responsive caregiving for fostering positive development early in life; however, tools measuring these interactions are often impractical for larger scale intervention trials and in settings with resource constraints. The present study provides reliability and validity evidence from Sindh, Pakistan for a tool developed to quantify responsive caregiving. Data were collected from 200 randomly selected households on responsive caregiving, sociodemographic characteristics, early learning, and early child development. The results indicated that the responsive care tool can be feasibly administered in less than 5 min in a low-resource setting. An exploratory factor analysis found that the tool’s indicators reliably loaded onto two distinct factors, responsive interactions and caregiver-initiated interactions, accounting for 96.01% of the underlying variation in scores. A confirmatory factor analysis reflecting input from modification indices showed satisfactory fit statistics and adequate factor loadings (all above .70). Internal consistencies of the two factors were also high, with alphas of .93 and .83, respectively. Convergent validity of the responsive interactions factor was demonstrated by a strong and positive correlation with measures of psychosocial stimulation, early learning, maternal education, and household wealth. Predictive validity of the responsive interactions factor was demonstrated by a strong and positive association with child development. The caregiver-initiated interactions factor was significantly and negatively associated with psychosocial stimulation and child development. The resulting evidence provides programs with an open access, observational, reliable, and valid measure to quantify responsive caregiving at the program level in low-resource settings.

Measuring CSF shunt flow with MRI using flow enhancement of signal intensity (FENSI).

To develop and validate a noninvasive imaging technique for accurately assessing very slow CSF flow within shunt tubes in pediatric patients with hydrocephalus, aiming to identify obstructions that might impede CSF drainage. A simulation of shunt flow enhancement of signal intensity (shunt-FENSI) signal is used to establish the relationship between signal change and flow rate. The quantification of flow enhancement of signal intensity data involves normalization, curve fitting, and calibration to match simulated data. Additionally, a phase sweep method is introduced to accommodate the impact of magnetic field inhomogeneity on the flow measurement. The method is tested in flow phantoms, healthy adults, intensive care unit patients with external ventricular drains (EVD), and shunt patients. EVDs enable shunt-flow measurements to be acquired with a ground truth measure of CSF drainage. The flow-rate-to-signal simulation establishes signal-flow relationships and takes into account the T1 of draining fluid. The phase sweep method accurately accounts for phase accumulation due to frequency offsets at the shunt. Results in phantom and healthy human participants reveal reliable quantification of flow rates using controlled flows and agreement with the flow simulation. EVD patients display reliable measures of flow rates. Shunt patient results demonstrate feasibility of the method and consistent flow rates for functional shunts. The results demonstrate the technique's applicability, accuracy, and potential for diagnosing and noninvasively monitoring hydrocephalus. Limitations of the current approach include a high sensitivity to motion and strict requirement of imaging slice prescription.

Psychometric properties of the Turkish version of Central Sensitization Inventory-9 in patients with chronic musculoskeletal pain.

The aim of the study was to assess the psychometric properties of the Turkish version of Central Sensitization Inventory-9 (CSI-9) in patients with chronic musculoskeletal pain. The methodological study included 92 patients with chronic musculoskeletal pain. The original version of the CSI-9 was translated and culturally adapted into Turkish. The internal consistency and test-retest reliability were evaluated with Cronbach's α and the intraclass correlation coefficient (ICC), respectively. The assessment of reproducibility was conducted with the standard error of measurement (SEM) and minimal detectable difference (MDD) values. Convergent validity was explored by correlation analysis between the CSI-9 and Central Sensitization Inventory (CSI-25), Brief Pain Inventory (BPI), and European Quality of Life Survey-5 Dimensions (EQ-5D). The structural validity was assessed with factor analysis. Floor and ceiling effects were also analyzed. We found a very good internal consistency (Cronbach's α of 0.83) and excellent test-retest reliability (ICC of 0.96) of the Turkish CSI-9. The SEM demonstrated a range between 0.19 and 1.12, and the MDD was observed to vary from 1.17 to 1.35. The CSI-9 correlated significantly with the CSI-25 ( r = 0.77, P < 0.001), the pain severity subscale of the BPI ( r = 0.41 to 0.53, P < 0.001), the pain interference subscale of the BPI ( r = 0.21 to 0.58, P = 0.02 to P < 0.001), the EQ-5D ( r = 0.24 to 0.48, P < 0.05), and the EQ-5D visual analog scale ( r = -0.41, P < 0.001). One factor was identified within the CSI-9. Our data suggest that the Turkish CSI-9 is reliable and valid outcome measure for assessing CS in patients with chronic musculoskeletal pain.

Validating the Fatigue Scale for Motor and Cognitive Function (FSMC) in chronic stroke.

Post-stroke fatigue can manifest as both physical and mental fatigue. The Fatigue Scale for Motor and Cognitive Functions (FSMC) evaluates fatigue on the motor and cognitive domains separately, however, the psychometric properties of this measure in stroke have not been reported. To determine the internal consistency, test-retest reliability, and concurrent validity of the FSMC in chronic stroke. Thirty-four participants with chronic stroke (55.26±12.27 years of age; 59.53±89.21 months post-stroke) completed the FSMC on two separate visits. Internal consistency and reliability of the FSMC were examined using Cronbach's alpha and two-way mixed effects intraclass correlation coefficients (ICC), respectively. Correlation between the FSMC and the Fatigue Severity Scale and Visual Analog Scale-Fatigue was used to assess concurrent validity. Internal consistency was excellent (Cronbach's alpha > 0.9) and reliability was moderate to good (ICC = 0.72-0.81) for all FSMC scores. The FSMC demonstrated moderate to good concurrent validity with the Fatigue Severity Scale (ρ= 0.66-0.72) but only fair concurrent validity with the Visual Analog Scale-Fatigue (ρ= 0.37-0.44). The FSMC is a valid and reliable measure of post-stroke fatigue and may be a useful tool to examine physical fatigue and cognitive fatigue in chronic stroke.

The Hemodialysis Distress Thermometer for Caregivers (HD-DT-C): development and testing of the psychometric properties of a new tool for screening psychological distress among family caregivers of adults on hemodialysis.

To develop and test the measurement properties of the HD-DT-C, a new tool designed to facilitate the screening of psychological distress and its sources in family caregivers of adults on hemodialysis. The present investigation was carried out in three phases: Phase 1 focused on the process of developing and exploring the content validity and clinical utility of the HD-DT-C using a mixed-methods approach and feedback panels; Phase 2, where the psychometric properties of this new tool were tested in a cross-sectional study (n = 106 caregivers); and Phase 3, where the European Portuguese version of the HD-DT-C was translated and culturally adapted into American English using a forward-backward translation procedure, followed by an expert panel review. Findings suggested that the HD-DT-C was perceived by feedback panels as practical, appropriate, and useful for increasing dialysis provider/family caregiver communication in nephrology centers. The European Portuguese version of the HD-DT-C showed good test-retest reliability (ICC = 0.991 for the barometer and κ ≥ 0.80 in 77% of the checklist items), high diagnostic accuracy (AUC = 0.956), and strong convergent validity (all r ≥ 0.50) with reference measures that assess quality of life, caregiver burden, and symptoms of anxiety and depression. Cutoff scores with good clinical utility (CUI + ≥ 0.70) were recommended for screening distress in research (≥ 6) and clinical practice (≥ 5). The HD-DT-C is a brief, reliable, valid, and acceptable measure for identifying self-reported psychological distress and its sources among people caring for a family member or friend on hemodialysis. Future research is needed to explore the measurement properties of the American English version of this new tool.

Refining and adapting the measurement properties of evidence-based practice measures for physiotherapy students.

There is a lack of reliable and valid evidence-based practice (EBP) measures for physiotherapy students. This study validated EBP-student (EBP-S) measures for physiotherapy students. EBP measures developed from previous research were cross-culturally validated for use by physiotherapy students. The adapted EBP-S consisted of six measures: use of EBP, EBP activities, EBP knowledge, self-efficacy for EBP, attitudes towards EBP, and perceptions of the teaching and assessment of EBP in the curriculum. The final version was completed by physiotherapy students (n = 335). The psychometric properties for each EBP-S measure were estimated, including construct validity using Rasch model, internal consistency reliability using person separation index (PSI), test-retest reliability using intraclass correlation coefficient (ICC), and differential item functioning (DIF). Two formative measures (use of EBP and EBP activities) were only linguistically modified for use with students. A Rasch model was applied to the other four reflective measures. For knowledge, 55% (6/11) items fit the Rasch model with chi-square fit statistic (χ2) = 34.46, p = 0.08; PSI = 0.85. For self-efficacy, 89% (8/9) items fit the Rasch model with χ2 = 25.11, p = 0.80; PSI = 0.89. For attitudes, 62% (8/13) items fit the Rasch model with χ2 = 61.49, p = 0.00; PSI = 0.71. For perception of the teaching and assessment of EBP in the curriculum, 62% (8/13) items fit the Rasch model with χ2 = 80.99, p = 0.45; PSI = 0.92. perception of the teaching and assessment of EBP in the curriculum showed DIF in three items. The ICCs ranged between 0.80 and 0.98. The EBP-S measures were validated for physiotherapy students, including the testing of psychometric properties, which were not tested in the original studies. Further refinements should be considered for the use of the EBP-S with other groups of students or if changes are applied to the current curriculum.

A generating family of unit-Garima distribution: Properties, likelihood inference, and application

This article proposes the unit Garima (UGa) distribution for analysing proportion data. Some statistical properties of the UGa distribution are investigated, including survival and hazard functions, order statistics, quantile function, and stress-strength reliability measure. Next, a new family of continuous distributions, called the unit Garima-generated (UGa-G) family of distributions, is studied. The UGa-G family of distributions has the feature to use the UGa distribution as the main generator and the concept of the T-X family of distributions. Some UGa-G family sub-models are provided, such as the UGa-Beta, UGa-Weibull, and UGa-normal distributions. The maximum likelihood method is used to estimate the model parameters for the statistical aspect. A Monte Carlo simulation for the percentile bootstrap confidence intervals for each parameter of the proposed distributions is provided. Applications to eight practical data sets are given to demonstrate the usefulness of the proposed distributions.

Slovenian version of the Stroke and Aphasia Quality of Life Scale 39-Generic Version (SAQOL-39g): Psychometric properties

ABSTRACT Purpose Aphasia, which is one of the most common consequences of stroke, has severe impact on everyday life. Quality of life in persons with aphasia changes dramatically. In the recent years, there has been a lot of interest in assessing health-related quality of life, but few questionnaires are adapted to people with aphasia (PwA). The Stroke Aphasia Quality of Life-39 scale (SAQOL-39) Generic Version is suitable for people with and without aphasia. Our study examined the reliability and validity of a translation of the SAQOL-39 g into Slovenian in Slovenian-speaking PwA. Methods Translation, back-translation from English into Slovenian language was performed. Seventy-three PwA with broad range of severity and times post-onset of stroke were included in the study of psychometric properties of the Slovenian translation. Results The psychometric properties in Slovenian version were quite similar to other languages, with high internal consistency and test-retest reliability (Cronbach alpha > 0.94; ICC ≥0.99). Conclusion The Slovenian translation of the SAQOL-39 g is a valid and reliable measure of quality of life in PwA. It can be clinically used as an additional tool for goal setting in Slovenian PwA.

Psychometric Assessment of the Rett Syndrome Caregiver Assessment of Symptom Severity (RCASS).

Rett syndrome is a severe neurodevelopmental disorder that affects about 1 in 10,000 females. Clinical trials of disease modifying therapies are on the rise, but there are few psychometrically sound caregiver-reported outcome measures available to assess treatment benefit. We report on a new caregiver-reported outcome measure, the Rett Caregiver Assessment of Symptom Severity (RCASS). Using data from the Rett Natural History Study (n = 649), we examined the factor structure, using both exploratory and confirmatory factor analysis, and the reliability and validity of the RCASS. The four-factor model had the best overall fit, which covered movement, communication, behavior, and Rett-specific symptoms. The RCASS had moderate internal consistency. Strong face validity was found with age and mutation type, and convergent validity was established with other similar measures, including the Revised Motor-Behavior Assessment Scale, Clinical Severity Scale, Clinical Global Impression Scale, and the Child Health Questionnaire. These data provide initial evidence that the RCASS is a viable caregiver-outcome measure for use in clinical trials in Rett syndrome. Future work to assess sensitivity to change and other measures of reliability, such as test-retest and inter-rater agreement, are needed.

The reliability, validity and clinical utility of the Clinical Outcomes in Routine Evaluation - ten-item version (CORE-10) in post-acute patients with stroke.

To explore the validity, reliability, and clinical utility of the Clinical Outcomes in Routine Evaluation - ten-item version (CORE-10: a ten-item questionnaire designed to measure psychological distress) in a stroke inpatient sample and calculate reliable and clinically significant change scores. A post-acute stroke rehabilitation ward in the East of England. A total of 53 patients with stroke, capable of completing the CORE-10 as part of their routine clinical assessment. Exclusion criteria included moderate to severe aphasia and/or alexia. Alongside the CORE-10, the Patient Health Questionnaire - 9, the Hospital Anxiety and Depression Scale, the Centre for Epidemiological Studies-Depression Scale, and the Beck Depression Inventory Second Edition were used as concurrent measures. To assess reliability, the internal consistency and test-retest reliability of the CORE-10 were calculated. The average number of days between CORE-10 test-retest administrations was 2.84 (SD = 3.12, Mdn = 1). Concurrent validity was assessed by examining correlations between the CORE-10 and comparable measures, and clinical utility was assessed using the criteria of Burton and Tyson (2015). The internal consistency (Cronbach's alpha) for the CORE-10 was .80, and test-retest reliability interclass correlation coefficient was .81. Total score correlations between the CORE-10 and concurrent measures ranged from r = .49 to r = .89. The CORE-10 achieved the maximum score (i.e. 6/6) on criteria for clinical utility. Calculations demonstrated a reliable change index of nine points and a clinically significant change cut point of 12 on the CORE-10. Percentiles for CORE-10 total scores are reported. This study provides preliminary support for the CORE-10 as a valid and reliable measure that has clinical utility for screening distress in inpatients with stroke.

Reliability and validity of the medial standing overhead arm reach (SOAR) test as a measure of functional hip adduction motion.

The Posterior Standing Overhead Arm Reach (SOAR) test has been previously reported as a reliable clinical measure of closed chain hip extension motion. The proposed Medial SOAR test expands on that testing approach to provide a similar measure of functional hip adduction motion. This was a preliminary intrarater and interrater reliability and validity study of the Medial SOAR test as a measure of functional hip adduction. Cross-sectional. University motion analysis laboratory. Fifty hips were assessed in 25 (22 female) asymptomatic participants (mean age = 23.4 years, SD = 0.8). Maximum hip adduction during the Medial SOAR test was measured with a standard goniometer independently by two examiners. The test was also performed using three-dimensional motion capture. The intrarater and interrater reliability of the goniometric measure was determined using intraclass correlation coefficients, and the relationship between measures obtained via goniometry and three-dimensional motion capture was assessed with Pearson correlations and Bland-Altman analysis. Intrarater reliability (ICC2,3) was 0.88 (95% CI = 0.80-0.92) for Examiner 1 and 0.87 (95% CI = 0.79-0.92) for Examiner 2. The standard error of measurement and minimal detectable change were less than 3.0°. Interrater reliability demonstrated an intraclass correlation coefficient = 0.62 (95% CI = 0.28-0.79). Pearson correlations were significant with low-to-moderate associations (r = 0.49, P < 0.001; r = 0.24, P = 0.045). Similar to the previously reported Posterior SOAR test, the Medial SOAR test demonstrated acceptable intrarater and interrater reliability, along with low-to-moderate associations with three-dimensional motion capture. The Medial SOAR test has the potential to provide a reliable and accurate assessment of closed chain hip adduction.

Evidence of Validity, Invariance, and Reliability of the Body Image Dimension in the Body Investment Scale: A Study in Spanish University Students

Background: This study focused on the widely used Body Image subscale, a dimension of the Body Investment Scale developed by Orbach and Mikulincer in 1998. Specifically, we explored its psychometric properties and potential use for health promotion research among young Spanish university students. Method: A sample of 793 participants (75.28% female) aged 18–26 years (M = 20.68; SD = 2.13) completed the questionnaire and related variables. Results: A unidimensional structure was confirmed with a good fit, demonstrating gender- and age-invariance, along with robust internal consistency. The scale exhibited a significant association with self-esteem, life satisfaction, a sense of coherence, and psychological distress. Conclusions: The Body Image subscale can be considered unidimensional. The obtained factor solution provides a reliable, valid, and invariant measure across gender and age for assessing body feelings in Spanish university students. Therefore, the instrument can effectively investigate the relationship between body image and health-related behaviors. Additionally, it can serve as a valuable tool in designing effective health interventions for university students to prevent mental health conditions, such as eating disorders or suicidal behaviors.

A Novel Grading System for Diffuse Chorioretinal Atrophy in Pathologic Myopia.

This study aims to quantitatively assess diffuse chorioretinal atrophy (DCA) in pathologic myopia and establish a standardized classification system utilizing artificial intelligence. A total of 202 patients underwent comprehensive examinations, and 338 eyes were included in the study. The methodology involved image preprocessing, sample labeling, employing deep learning segmentation models, measuring and calculating the area and density of DCA lesions. Lesion severity of DCA was graded using statistical methods, and grades were assigned to describe the morphology of corresponding fundus photographs. Hierarchical clustering was employed to categorize diffuse atrophy fundus into three groups based on the area and density of diffuse atrophy (G1, G2, G3), while high myopic fundus without diffuse atrophy was designated as G0. One-way analysis of variance (ANOVA) and nonparametric tests were conducted to assess the statistical association with different grades of DCA. On the basis of the area and density of DCA, the condition was classified into four grades: G0, G1 (0 < density ≤ 0.093), G2 (0.093 < density ≤ 0.245), and G3 (0.245 < density ≤ 0.712). Fundus photographs depicted a progressive enlargement of atrophic lesions, evolving from punctate-shaped to patchy with indistinct boundaries. DCA atrophy lesions exhibited a gradual shift in color from brown-yellow to yellow-white, originating from the temporal side of the optic disc and extending towards the macula, with severe cases exhibiting widespread distribution throughout the posterior pole. Patients with DCA were significantly older [34.00 (27.00, 48.00) vs 29.00 (26.00, 34.00) years], possessed a longer axial length (28.85 ± 1.57 vs 27.11 ± 1.01 mm), and exhibited a more myopic spherical equivalent [- 13.00 (- 16.00, - 10.50) vs - 9.09 ± 2.41 D] compared to those without DCA (G0) (all P < 0.001). In eyes with DCA, a trend emerged as grades increased from G1 to G3, showing associations with older age, longer axial length, deeper myopic spherical equivalent, larger area of parapapillary atrophy, and increased fundus tessellated density (all P < 0.001). The novel grading system for DCA, based on assessments of area and density, serves as a reliable measure for evaluating the severity of this condition, making it suitable for widespread application in the screening of pathologic myopia.

Reliability and Performance Evaluation of Safety-Critical Instrumentation and Control Systems of Nuclear Power Plant

Instrumentation and control systems are nervous systems of nuclear power plant (NPP). These systems interact with several safety-critical components of the NPP, such as actuators, transformers, control valves, sensors, circuit breakers, signal processing units, controllers, and heat exchangers. Therefore, the failure of these systems could result in significant financial loss, harm to human resources, or environmental damage. As a result, these systems need to be highly reliable and accurate. In this article, we suggest a framework, based on the batch deterministic and stochastic Petri nets (BDSPNs) to measure the reliability and performance of safety-critical system. The framework consists of three phases. In the first phase, the system is modeled using the BDSPN to derive the transition rate among the system states. In phase 2, the transition rate matrix is utilized to compute the steady-state probability values, which help to evaluate the response time of the system using Little's law. The third phase uses a transition probability matrix to assess the reliability of the system. The technique is illustrated on shutdown system of NPP and is validated on the operational profile data. The obtained accuracy of 99.9905% in measurement of reliability validates the approach.

Comparison of the efficacy of 75 mg aspirin versus 150 mg aspirin for prevention of preeclampsia in patients at high risk for preeclampsia

BACKGROUND &amp; OBJECTIVE: Preeclampsia is a significant contributor to maternal health challenges. Emphasizing prevention over cure is a guiding principle in healthcare. As a reliable measure to forestall hypertension and its associated complications during pregnancy, aspirin is widely embraced. The early identification of risk factors plays a crucial role in the primary prevention of preeclampsia. Post-risk stratification, aspirin emerges as a pivotal player in the preventive strategy for individuals identified as high-risk for pre-eclampsia. To assess the effectiveness of 75 mg aspirin against 150 mg aspirin in preventing preeclampsia among individuals identified as having a high risk for the condition.&#x0D; METHODOLOGY: A quasi-experimental study was conducted in the Department of Obstetrics and Gynecology, Services Hospital, Lahore, from 27-12-2019 to 27-6-2020.240 patients were enrolled in the study, which was later divided into two groups. Group A received treatment with 75 mg aspirin, while Group B was administered 150 mg aspirin. Efficacy was determined based on whether blood pressure levels were below 140/90 mmHg, and proteinuria was rated as &lt;+1 using the dipstick method.&#x0D; RESULTS: The mean age of the patients was 28.54±6.83 years, and the mean gestational age of the patients was 15.30±1.69 weeks. In the 75 mg group, the efficacy was achieved in 94(78.3%) patients, whereas in the 150 mg group, the efficacy was achieved in 108(90.0%) patients (p-value=0.013).&#x0D; CONCLUSION: This study concludes that the efficacy of 150 mg aspirin significantly surpasses that of 75 mg aspirin in preventing preeclampsia among high-risk pregnant patients.

Reactive power capacity allocation technology of shore‐based power supply system of offshore oil production platform under different network topology reliability measures

AbstractTo improve the economy of offshore oil production platform shore‐based power transmission mode, the reactive power capacity allocation technology of offshore oil production platform shore‐based power supply system based on different network topology reliability measures was proposed. The optimization model of power supply system network topology and the structure model of voltage source converter high voltage direct current transmission system were established, the start and stop control scheme of flexible direct current (DC) transmission system was designed, and the operation parameters of converter station and DC line were monitored in real time. The topological structure of offshore oil production platform shore‐based power supply system is constructed, the mathematical model of flexible DC transmission system is established when the alternating current side voltage is balanced, the reactive power capacity configuration of offshore oil production platform shore‐based power supply system is optimized, and the life cycle cost results are calculated. The experimental results show that the algorithm proposed in this paper can obtain the optimal solution only after 26 calculations, with high optimization efficiency and good convergence effect. Reactive capacity configuration of shore‐based power supply system for offshore production platform can reduce failure rate and life cycle cost.

Psychometric properties of the Buss-Perry Aggression Questionnaire-short form among law enforcement officers.

Repeatedly capturing national headlines, excessive law enforcement officer (LEO) use of force in critical incident encounters is one of the most divisive human rights issues in the United States. Valid and reliable measures of potential precursors to LEO excessive use of force, such as aggression, are needed. The Buss-Perry Aggression Questionnaire-short form (BPAQ-SF) is a validated measure of aggression across various populations; however, evaluation of this easily administered measure in high-stress, frontline populations such as LEOs is limited. The primary goal of this study was to evaluate the validity, reliability, and sensitivity to change the BPAQ-SF in a sample of LEOs. A confirmatory factor analysis suggested that the hierarchical solution provides a mixed fit to the data:SBχ²(25.84) = 62.50, p = .0001; comparative fit index = .94, non-normed fit index = .92, root mean square error of approximation = .19 (90% confidence interval = .17-.21), standardized root mean squared residual = .08. The BPAQ-SF demonstrated good internal consistency (α = .84) and test-retest reliability (r = .86), correlations in the expected direction with predictors of and buffers against aggression, and sensitivity to change among LEOs who participated in an intervention targeting aggression. Results support and extend previous findings suggesting that the BPAQ-SF is a valid and reliable measure of aggression among LEOs.