Improved modified estimator for estimation of median using auxiliary information under simple random sampling.

This article aims to suggest an improved estimator for estimation of population median using auxiliary information under simple random sampling. The expression for the bias and mean square error are obtained up to first order approximation. We determine the MLE of the optimal values of the describing scalars. The proficiency of the suggested estimator is evaluated in comparison to the preliminary estimators using the MSE threshold. The suggested estimators are compared numerically to the ones that are currently studied in this study. The performance and novelty of the estimators was evaluated using real data sets and a simulation study. To check the efficiency of estimators empirical and theoretical study has been studied. Based on numerical result it is to be noted that our suggested estimator is more efficient as compared to existing estimators which is considered in this article in terms of least MSE and greater PRE.

New classes of difference cum-ratio-type exponential estimators for a finite population variance in stratified random sampling.

The problem of estimating the variance of a finite population is an important issue in practical situations where controlling variability is difficult. During experiments conducted in the fields of agriculture and biology, researchers often face this issue, resulting in outcomes that appear uncontrollable for the desired results. Using auxiliary information effectively has the potential to enhance the precision of estimators. This article aims to introduce improved classes of efficient estimators that are specifically designed to estimate the study variable's finite population variance. When stratified random sampling is used, these estimators are particularly efficient when the minimum and maximum values of the auxiliary variable are known. The bias and mean squared error (MSE) of the proposed classes of estimators are determined by a first-order approximation. In order to evaluate their performance and verify the theoretical results, we performed simulation research. The proposed estimators show higher percent relative efficiencies ( P R E s ) in all simulation scenarios compared to other existing estimators, according to the results. Three datasets are utilized in the application section, which are used to further validate the effectiveness of the proposed estimators.

Hybrid class of robust type estimators for variance estimation using mean and variance of auxiliary variable.

This study is completed for the estimation of unknown population variance for the variable of mean and variance of interest. To accomplish this task, a new generalized class of robust kind of variance estimators proposed utilizing known descriptives of auxiliary variable, for example, Mid-range, Hodges-Lehmann Mean, Tri-mean, deciles mean, coefficient of skewness, interquartile range, first quartile, coefficient of kurtosis, semi-interquartile average, inter decile range and Mean, etc. These conventional measures of auxiliary variable improve the accuracy of the suggested class under simple random sampling without replacement (SRSWOR) scheme. The properties such as the bias, mean square errors (MSE), and least MSE of the suggested class are derived up to first order of approximation. The superiority conditions of the developed class of estimators over existing estimators are also made out theoretically. Finally, numerical representation is also completed for the motivations behind the article. The usual variance estimator is considered as a benchmark for comparing all considered estimators in numerical illustration. The results have been indicated that the suggested class is performing better than the usual variance estimator and all other thoughts about existing estimators.

Enhanced exponential ratio-cum-ratio estimator in ranked set sampling using transformed auxiliary information.

Estimation of population mean is a determined subject issue in sampling surveys and many efforts have been paid by various researchers to enhance the precision of the estimates by utilizing the correlated auxiliary information. In connection with this, we suggest an improved exponential ratio-cum-ratio estimator using transformed auxiliary variables under ranked set sampling scheme. Theoretical comparison between estimators is made in terms of mean square errors (MSEs), percentage relative efficiencies (PREs), and percentage relative root mean squared error (PRRMSE). The numerical expression for the bias and MSE of the suggested estimator is derived up to first order of approximation. Based on the results of actual data sets and a simulation study, it is found that the suggested estimator perform well as compared to its existing counterparts.

Classical and Bayesian inference for the new four-parameter Lomax distribution with applications.

In this study, a new four-parameter Lomax distribution is proposed using a new alpha power transformation technique. The new distribution is named "New Alpha Power Transformed Power Lomax Distribution." Mathematical properties, including moments, the moment-generating function, the mean residual life, order statistics, and the quantile function, are obtained. The maximum likelihood estimation approach is used to estimate the model parameters. A comprehensive simulation is used to evaluate the behavior of maximum likelihood estimators. Two real-world data sets were used to demonstrate the significance of the proposed model, and the results show that the new model performs better when interpreting lifetime data sets. In the end, for the data sets, Bayesian estimation and Metropolis-Hasting's approach were also utilized to construct the approximate Bayes estimates, and convergence diagnostic methods based on Markov Chain Monte Carlo techniques were applied.

Exploring factors influencing patient activation in Saudi rheumatoid arthritis patients: A Nationwide Cross-Sectional Survey-Results from the COPARA study.

OBJECTIVES: To evaluate patient activation in rheumatoid arthritis (RA) patients using patient activation measure 13 (PAM-13) on a national level in Saudi Arabia. METHOD: A national survey was administered across multiple centers in Saudi Arabia. Patient activation was assessed using the PAM-13. The Compliance Questionnaire for Rheumatology (CQR) and the RA Impact of Disease (RAID) tool were also administered. The data from the survey were analyzed, and the results were stratified based on activation level. All factors affecting patient activation were explored and reported. RESULTS: A total of 1241 participants were included. Most of the patients were females (85%), the mean age was 47 (±14), and most patients lived in the central region (47%). The mean (±standard deviation) patient activation score was 578.7 (±13.0). Patient activation was affected by multiple factors: demographic characteristics, such as education, with a beta value of 1.11 (95% confidence interval [CI] 0.64 ̶1.58, p < .001). Higher CQR scores were associated with higher activation levels, with a beta value of 2.61 (95% CI 0.80 ̶4.44, p = .005), and higher RAID scores were associated with lower activation levels, with a beta value of 3.13 (95% CI 1.36 ̶4.91, p = .001). CONCLUSIONS: Patient activation was affected by several demographic characteristics and the impact of RA. A higher activation may improve compliance. Future longitudinal studies are required to confirm these findings and should explore the underlying mechanism of these effects.

On the development of new cosine-based probabilistic methods with applications to univariate and bivariate analyses of the wind speed energy.

So far in the literature, a number of probability distributions have been successfully implemented for analyzing the wind speed and energy data sets. However, there is no published work on modeling and analyzing the wind speed and energy data sets with probability distributions that are introduced using trigonometric functions. In the existing literature, there is also a lack of studies on implementing the bivariate trigonometric-based probability distributions for modeling the wind speed and energy data sets. In this paper, we take up a meaningful effort to cover these interesting research gaps. Thus, we first incorporate a cosine function and introduce a new univariate probability distributional method, namely, a univariate modified cosine-G (UMC-G) family. Using the UMC-G method, a new probability distribution called a univariate modified cosine-Weibull (UMC-Weibull) distribution is studied. We apply the UMC-Weibull distribution for analyzing the wind energy data set taken from the weather station at Sotavento Galicia, Spain. Furthermore, we also introduce a bivariate version of the UMC-G method using the Farlie-Gumble-Morgenstern copula approach. The proposed bivariate distributional method is called a bivariate modified cosine-G (BMC-G) family. A special member of the BMC-G distributions called a bivariate modified cosine-Weibull (BMC-Weibull) distribution is introduced. We apply the BMC-Weibull distribution for analyzing the bivariate data set representing the wind speed and energy taken from the weather station at Sotavento Galicia. Using different statistical tools, we observe that the UMC-Weibull and BMC-Weibull are the best-suited models for analyzing the wind speed and energy data sets.

Exploring Impact of Multidisciplinary Care on Patient Activation in Saudi Rheumatoid Arthritis Patients: A Cross-Sectional Survey-Extended Results from the COPARA National Project.

Introduction: Multidisciplinary setting in healthcare provide positive patient outcomes. Objective: To evaluate the impact of specialized rheumatology clinics (multidisciplinary settings) on the activation and engagement of rheumatoid arthritis (RA) patients. Material and Methods: This cross-sectional survey assessed patient activation using the patient activation measure-13. Participants attending Specialized Rheumatology Clinics (SRC multidisciplinary clinics) were compared with age- and sex-matched patients attending Standard of Care (SOC). The study was observational in nature, assessing several demographic and therapeutic options and their relation to the clinical setting and patient activation. Results: This study included 117 SRC matched RA patients with 117 SOC. The majority of the included patients were female (n=211, 90.2%), >40 years of age (n=177, 75.6%), and had intermediate-to-high education (n=147, 62.8%). Patients in the SRC were also more likely to have activation levels 3 and 4 with an odds ratio of 3.194 (95% confidence interval [CI] 1.835-5.562, p<0.001). In addition, SRC participants were more likely to be in levels 3 and 4 activation, even after adjustment for confounding variables, with an adjusted odds ratio of 2.401 (95% CI 1.121-4.758, p=0.012) and 2.175 (95% CI 1.127-4.196, p=0.020), respectively. Conclusion: Establishing SRC for RA patients seems to have a positive impact on patient activation and engagement and adds to the previously explored benefits of multidisciplinary care in chronic disease management.

Clinical Manifestations of Systemic Lupus Erythematosus in a Tertiary Center in Saudi Arabia.

Introduction Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with multisystemic involvement. The clinical presentation and immunological findings of SLE patients from different regions in Saudi Arabia have been studied. There have been no studies on the clinical manifestations of SLE in patients in Saudi Arabia's southern region. This article aims to explore the clinical manifestations of SLE in a tertiary center in the southern region of Saudi Arabia. Methods A retrospective study was carried out on 108 SLE patients who were seen in the rheumatology clinic at Aseer Central Hospital over six months from January 2022 to June 2022. Patients' demographics, clinical and serological characteristics, and therapeutic data were reviewed. Results The male-to-female ratio was 1:12.5, with a mean age at presentation of 28.6 ± 10 years. The mean disease duration was 9.06 ± 5.96 years. Mucocutaneous and musculoskeletal manifestations were the most common, accounting for 76% and 57% of all cases, respectively. Neuropsychiatric involvement and lupus nephritis were present in 29% and 31% of patients, respectively. The hematological abnormalities that were present included anemia (60%), leukopenia (37%), and thrombocytopenia (15%). Antinuclear antibody (ANA) was detected in 100%, anti-double-stranded DNA (anti-dsDNA) antibody in 55%, anti-Smith antibody in 13%, and hypocomplementemia in 52% of patients. Hydroxychloroquine was received by 98% and oral steroids by 41% of the patients. Other drugs include azathioprine (23%), mycophenolate mofetil (15%), methotrexate (23%), belimumab (9%), cyclophosphamide (10%), and rituximab (6%). Conclusion The main clinical features of our patients were in parallel with previous studies in Saudi Arabia as well as in Arab countries. We found a lower prevalence of lupus nephritis, serositis, and anti-dsDNA antibody. Further multicenter studies are required to investigate the long-term outcome and survival of SLE patients.

A new modification of the flexible Weibull distribution based on power transformation: Monte Carlo simulation and applications.

Statistical modeling is a crucial phase for decision-making and predicting future events. Data arising from engineering-related fields have most often complex structures whose failure rate possesses mixed state behaviors (i.e., non-monotonic shapes). For the data sets whose failure rates are in the mixed state, the utilization of the traditional probability models is not a suitable choice. Therefore, searching for more flexible probability models that are capable of adequately describing the mixed state failure data sets is an interesting research topic for researchers. In this paper, we propose and study a new statistical model to achieve the above goal. The proposed model is called a new beta power very flexible Weibull distribution and is capable of capturing five different patterns of the failure rate such as uni-modal, decreasing-increasing-decreasing, bathtub, decreasing, increasing-decreasing-increasing shapes. The estimators of the new beta power very flexible Weibull distribution are obtained using the maximum likelihood method. The evaluation of the estimators is assessed by conducting a simulation study. Finally, the usefulness and applicability of the new beta power very flexible Weibull distribution are shown by analyzing two engineering data sets. Using four information criteria, it is observed that the new beta power very flexible Weibull distribution is the best-suited model for dealing with failure times data sets.

A new trigonometric modification of the Weibull distribution: Control chart and applications in quality control.

In the most recent era, the extensions of the probability models via trigonometry methods have received great attention. This paper also offers a novel trigonometric version of the Weibull model called a type-I cosine exponentiated Weibull (for short "TICE-Weibull") distribution. The identifiability properties for all three parameters of the TICE-Weibull model are derived. The estimators of the TICE-Weibull model are derived by implementing the maximum likelihood approach. To demonstrate the effectiveness of the TICE-Weibull model, two applications from real-world phenomena are analyzed. In addition, the proposed statistical model is established for an attribute control chart based on a time-truncated life test. The advantage of the developed charts is examined based on the average run length (ARL). The necessary tables of shift sizes and various sample sizes are offered for numerous values of the distribution parameters, as well as specified ARL and shift constants. Some numerical examples are discussed for various scheme parameters to study the performance of the new TICE-Weibull attribute control charts. According to our search and a brief study of the statistical literature, there is no published work on the development of a control chart using new probability models that are introduced using the cosine function. This is the key motivation of this work, which fills this amazing and interesting research gap.

Image Exchange in the Middle East: a Survey.

Developing an enterprise approach to imaging technology rather than a radiology focus has recently increased. The communicator needs to be aware of this shift.The Middle East countries participated in the survey have confirmed the following major benefits of Medical Image Exchange: ✔ Fast access to both image and report ✔ Enable tele-services for second opinion, consulting and reporting ✔ Improve patient journey, workflow and diagnosis ✔ Allowed more patient engagement to be in place The Middle East countries that participated in this survey have agreed on the following shared challenges regarding Medical Imaging Exchange: ✔ Lack of enterprise imaging governance at the early stage of implementation. It will organize the who, when, and how. In addition, any fees and or payment involved for physicians ✔ Infrastructure availability to handle such large volume of data. Growing from mega-byte to petabyte per year is challenge for infrastructure. Cloud against On Premises-Installation implementation model ✔ Interoperability and integration to connect multi specialties from different systems. In addition, how far existing systems are ready for that. A standard-based framework is mature for image exchange, but what follows for other domains? There is a need to move beyond radiology images so as to include images from pathology, ophthalmology, and dermatology There are other countries in the region requiring guidance, support, and funding to move forward from the compact disc into internet-based interoperable image exchange. This should be considered part of the World Health Organization and the United Nation development to the region in the healthcare sector.

Exploring Factors Influencing Medication Compliance in Saudi Rheumatoid Arthritis Patients: A Nationwide Cross-Sectional Survey - Results from the COPARA Study.

Purpose: Compliance is essential to achieve treatment goals in rheumatoid arthritis (RA) patients. The current study evaluated compliance and related factors in a large and diverse population. Patients and Methods: Patients with RA who received active treatment were invited to participate in an online survey. The Arabic versions of the 5-Item Compliance Questionnaire for Rheumatology (ACQR-5) and the RA Impact of Disease (RAID) were used to measure compliance and disability, respectively. The patients were sub-grouped based on background disease-modifying anti-rheumatic drugs (DMARDs). Variables associated with high compliance were selected for the logistic regression analysis. Results: A total of 1241 patients completed the survey and were included in the final analysis. Of those, 1055 (85%) were females with a mean (±SD) age and disease duration of 47.14 ± 13.71 and 8.77 ± 7.43 years, respectively. The mean RAID was 4.4±2.58, with 980 (79%) having an unacceptable level state. Patients with an unacceptable RAID level had a lower compliance rate (78.8% vs 85.8%, p = 0.001). Demographics associated with high compliance were female sex and increased age, with reported odds ratios of 1.018 (95% CI: 1.007-1.028) and 1.464 (95% CI: 1.016-2.108), respectively. Compliance was similar between patients on Janus kinase inhibitors or biological DMARDs (88.14% vs 80.83%, p = 0.17), between monotherapy, double therapy, or triple therapy recipients (80% vs 82.23% vs 81.32%, p = 0.665), and between patients receiving injectable and oral therapy (77.32% vs 81.14%, p = 0.246). Conclusion: A high compliance level was observed in this population, with patient demographics influencing compliance rather than the medication type or route of administration. Interventional studies should focus on the of high-risk patients identified in this study.

Patterns of Response to Different Treatment Strategies in Seropositive Rheumatoid Arthritis Patients in a Tertiary Hospital in South-Western Saudi Arabia: A Retrospective Study.

PURPOSE: To study the pattern of response to different treatment strategies in seropositive rheumatoid arthritis (RA) patients and to describe our clinical practice in RA management. PATIENTS AND METHODS: Over a period of two years from April 2018 to April 2020, we conducted a retrospective analysis of data for 288 consecutive seropositive RA patients attending rheumatology clinics and the daycare unit at Aseer Central Hospital. Data were collected on patient demographics, disease duration, extraarticular manifestations, comorbidities and treatment. Disease activity was assessed using the clinical disease activity index (CDAI). RESULTS: Out of the total 288 patients, 42% (120) are on csDMRADs, while 54% (162) are on bDMRADs and 4% (6) are on tsDMARDs. Of the patients on csDMARDS, 51%, 43% and 7% of them were on remission, low and moderate disease activity, respectively. However, of the patients on non-csDMARDS, 36.3%, 49.4% and 14.3% of them were on remission, low and moderate disease activity, respectively. Failure of csDMARDs was affected by the presence of high disease activity at baseline, extraarticular lung manifestations and coexistent fibromyalgia, with a significant effect of the latter on remission rate. Among patients on non-csDMARDs, 42 (25%) showed one or more therapy changes. Tumor necrosis factor inhibitors were the predominant first-line agents in biologically naive patients (65%) followed by abatacept (18%). Abatacept was the most frequently prescribed second biologic in 52% of cases followed by tocilizumab in 19%. CONCLUSION: The current clinical practice in our hospital is consistent with the latest American College of Rheumatology (ACR)/The European League Against Rheumatism (EULAR) guidelines. Treat-to-target strategy was achieved in the vast majority of our patients, while remission was observed in almost half of the patients.

Unusual Presentation of Rosai-Dorfman Disease: Report of a Rare Case.

BACKGROUND Rosai-Dorfman disease is a rare disorder that was previously described as sinus histiocytosis with massive lymphadenopathy. The disease is derived from overproduction of monocytes, which play an important role in immunity. The overproduction of macrophages will lead to accumulation of the cells in the affected tissue. CASE REPORT A 40-year-old Saudi male presented with shortness of breath with joint pain starting 3 months prior. His main complaints were a dry cough, bilateral neck swelling, dry mouth, dry skin, itchy eyes, and general fatigability. Physical examination showed that the patient had prominent bilateral parotid swelling that measured roughly 5 by 3 cm, which was firm and tender, with a smooth surface and no local signs of inflammation. Joint examination revealed non-tender and non-swollen joints, with mild limitations of movement. Eye examination revealed dry eyes after having a positive Schirmer test. For diagnosis, the patient underwent complete blood count, autoantibody, histopathology, immunohistochemistry, and radiological assessment. The histopathological study confirmed Rosai-Dorfman disease. Rosai-Dorfman disease can involve various presentations, as in this patient, who exhibited a highly unusual presentation in association with autoimmune disease. CONCLUSIONS Rosai-Dorfman disease must be considered as differential diagnosis in patients who present with bilateral lymphadenopathy with multisystem complaints, as the disease can present with various characteristics.