A Noncentral Lindley Construction Illustrated in an INAR(1) Environment

This paper proposes a previously unconsidered generalization of the Lindley distribution by allowing for a measure of noncentrality. Essential structural characteristics are investigated and derived in explicit and tractable forms, and the estimability of the model is illustrated via the fit of this developed model to real data. Subsequently, this model is used as a candidate for the parameter of a Poisson model, which allows for departure from the usual equidispersion restriction that the Poisson offers when modelling count data. This Poisson-noncentral Lindley is also systematically investigated and characteristics are derived. The value of this count model is illustrated and implemented as the count error distribution in an integer autoregressive environment, and juxtaposed against other popular models. The effect of the systematically-induced noncentrality parameter is illustrated and paves the way for future flexible modelling not only as a standalone contender in continuous Lindley-type scenarios but also in discrete and discrete time series scenarios when the often-encountered equidispersed assumption is not adhered to in practical data environments.

Clinical Relevance of Absolute BK Polyoma Viral Load Kinetics in Patients With Biopsy Proven BK Polyomavirus Associated Nephropathy

Introduction: The absolute BK viral load is an important diagnostic surrogate for BK polyomavirus associated nephropathy (PyVAN) after renal transplant (KTX) and serial assessment of BK viremia is recommended. However, there is no data indicating which particular viral load change, i.e., absolute vs. relative viral load changes (copies/ml; percentage of the preceding viremia) is associated with worse renal graft outcomes.Materials and Methods: In this retrospective study of 91 biopsy proven PyVAN, we analyzed the interplay of exposure time, absolute and relative viral load kinetics, baseline risk, and treatment strategies as risk factors for graft loss after 2 years using a multivariable Poisson-model.Results: We compared two major treatment strategies: standardized immunosuppression (IS) reduction (n = 53) and leflunomide (n = 30). The median viral load at the index biopsy was 2.15E+04 copies/ml (interquartile range [IQR] 1.70E+03–1.77E+05) and median peak viremia was 3.6E+04 copies/ml (IQR 2.7E+03–3.3E+05). Treatment strategies and IS-levels were not related to graft loss. After correction for baseline viral load and estimated glomerular filtration rate (eGFR), absolute viral load decrease/unit remained an independent risk factor for graft loss [incidence rate ratios [IRR] = 0.77, (95% CI 0.61–0.96), p = 0.02].Conclusion: This study provides evidence for the prognostic importance of absolute BK viremia kinetics as a dynamic parameter indicating short-term graft survival independently of other established risk factors.

Decreasing Laboratory Testing for Neonatal Jaundice Through Revision of a Clinical Practice Pathway

OBJECTIVES: The purpose of this study was to minimize unnecessary laboratory services for hospitalized neonates with hyperbilirubinemia by revising a local clinical practice pathway (CPP). METHODS: A retrospective cohort study was performed to compare the number of laboratory tests and blood draws in patients hospitalized with neonatal hyperbilirubinemia before and after implementation of a revised CPP. The study included infants with neonatal hyperbilirubinemia <14 days old admitted after their birth hospitalization between April 2017 and October 2019. Primary outcome measures included the total number of blood draws and the number of laboratory tests obtained per patient and length of stay. Secondary outcome measures included 7-day readmission rate, charges, and discharge bilirubin level. RESULTS: The median number of blood draws per patient after implementation of the CPP decreased to 2 (interquartile range [IQR], 2–3) compared with 3 (IQR, 2–3) before implementation (Poisson model–based estimated mean difference, 1.1; 95% confidence interval, 1.0–1.3; P = .018). The median number of laboratory tests per patient after implementation decreased from 4 (IQR, 3–6) to 3 (IQR, 2–4; Poisson model–based estimated mean difference, 1.3; 95% confidence interval, 1.2–1.5; P < .0001). There was no significant change in length of stay, readmission rate, charges, or discharge bilirubin level. CONCLUSIONS: Implementation of a revised CPP was associated with a significant decrease in the number of blood draws and laboratory tests per patient for infants admitted to the hospital for neonatal hyperbilirubinemia.

A data quality assessment of the first four years of malaria reporting in the Senegal DHIS2, 2014–2017

Background As the global burden of malaria decreases, routine health information systems (RHIS) have become invaluable for monitoring progress towards elimination. The District Health Information System, version 2 (DHIS2) has been widely adopted across countries and is expected to increase the quality of reporting of RHIS. In this study, we evaluated the quality of reporting of key indicators of childhood malaria from January 2014 through December 2017, the first 4 years of DHIS2 implementation in Senegal. Methods Monthly data on the number of confirmed and suspected malaria cases as well as tests done were extracted from the Senegal DHIS2. Reporting completeness was measured as the number of monthly reports received divided by the expected number of reports in a given year. Completeness of indicator data was measured as the percentage of non-missing indicator values. We used a quasi-Poisson model with natural cubic spline terms of month of reporting to impute values missing at the facility level. We used the imputed values to take into account the percentage of malaria cases that were missed due to lack of reporting. Consistency was measured as the absence of moderate and extreme outliers, internal consistency between related indicators, and consistency of indicators over time. Results In contrast to public facilities of which 92.7% reported data in the DHIS2 system during the study period, only 15.3% of the private facilities used the reporting system. At the national level, completeness of facility reporting increased from 84.5% in 2014 to 97.5% in 2017. The percentage of expected malaria cases reported increased from 76.5% in 2014 to 94.7% in 2017. Over the study period, the percentage of malaria cases reported across all districts was on average 7.5% higher (P < 0.01) during the rainy season relative to the dry season. Reporting completeness rates were lower among hospitals compared to health centers and health posts. The incidence of moderate and extreme outlier values was 5.2 and 2.3%, respectively. The number of confirmed malaria cases increased by 15% whereas the numbers of suspected cases and tests conducted more than doubled from 2014 to 2017 likely due to a policy shift towards universal testing of pediatric febrile cases. Conclusions The quality of reporting for malaria indicators in the Senegal DHIS2 has improved over time and the data are suitable for use to monitor progress in malaria programs, with an understanding of their limitations. Senegalese health authorities should maintain the focus on broader adoption of DHIS2 reporting by private facilities, the sustainability of district-level data quality reviews, facility-level supervision and feedback mechanisms at all levels of the health system.

Optimization of Bayesian repetitive group sampling plan for quality determination in Pharmaceutical products and related materials

Sampling plans are extensively used in pharmaceutical industries to test drugs or other related materials to ensure that they are safe and consistent. A sampling plan can help to determine the quality of products, to monitor the goodness of materials and to validate the yields whether it is free from defects or not. If the manufacturing process is precisely aligned, the occurrence of defects will be an unusual occasion and will result in an excess number of zeros (no defects) during the sampling inspection. The Zero Inflated Poisson (ZIP) distribution is studied for the given scenario, which helps the management to take a precise decision about the lot and it can certainly reduce the error rate than the regular Poisson model. The Bayesian methodology is a more appropriate statistical procedure for reaching a good decision if the previous knowledge is available concerning the production process. This article proposed a new design of the Bayesian Repetitive Group Sampling plan based on Zero Inflated Poisson distribution for the quality assurance in pharmaceutical products and related materials. This plan is studied through the Gamma-Zero Inflated Poisson (G-ZIP) model to safeguard both the producer and consumer by minimizing the Average Sample Number. Necessary tables and figures are constructed for the selection of optimal plan parameters and suitable illustrations are provided that are applicable for pharmaceutical industries.

Queuing Theory in Traffic Management System

In cities where the number of vehicles has consistently expanded faster than the transportation infrastructure available to serve them. More on queuing theory and its crucial application has been discussed in the current study. In Thudiyalur, Gandhipuram, and Periyanaickenpalayam, all in Coimbatore, this research examines the usefulness of queuing theory in the field of traffic management. The concept of traffic intensity isapplied to a set of areas in queuing theory in this study. Keywords: Traffic intensity, Queuing theory, Single server Poisson model

Predictive value of isolated symptoms for diagnosis of SARS-CoV-2 infection in children tested during peak circulation of the delta variant

Background: COVID-19 testing policies for symptomatic children attending U.S. schools or daycare vary, and whether isolated symptoms should prompt testing is unclear. We evaluated children presenting for SARS-CoV-2 testing to determine if the likelihood of having a positive SARS-CoV-2 test differed between participants with one versus ≥ 2 symptoms, and to examine the predictive capability of isolated symptoms. Methods: Participants ≤ 18 years presenting for clinical SARS-CoV-2 molecular testing in six sites in urban/suburban/rural Georgia (July-October, 2021; delta variant predominant) were queried about individual symptoms. Participants were classified into three groups: asymptomatic, one symptom only, or ≥ 2 symptoms. SARS-CoV-2 test results and clinical characteristics of the three groups were compared. Sensitivity, specificity, and positive/negative predictive values (PPV/NPV) for isolated symptoms were calculated by fitting a saturated Poisson model. Results: Of 602 participants, 21.8% tested positive and 48.7% had a known or suspected close contact. Children reporting one symptom (n=82; OR=6.00, 95% CI: 2.70-13.33) and children reporting ≥ 2 symptoms (n=365; OR=5.25: 2.66-10.38) were significantly more likely to have a positive COVID-19 test than asymptomatic children (n=155), but they were not significantly different from each other (OR=0.88: 0.52-1.49). Sensitivity/PPV were highest for isolated fever (33%/57%), cough (25%/32%), and sore throat (21%/45%); headache had low sensitivity (8%) but higher PPV (33%). Sensitivity/PPV of isolated congestion/rhinorrhea were 8%/9%. Conclusions: With high delta variant prevalence, children with isolated symptoms were as likely as those with multiple symptoms to test positive for COVID-19. Isolated fever, cough, sore throat, or headache, but not congestion/rhinorrhea, offered highest predictive value.

Indirect Impact of COVID-19 Vaccination on Weekly Trends in Morbidity and Mortality Indicators in Brazil, 2020 to 2021

Background: With the outbreak of the COVID-19 pandemic, safe and efficacious vaccines were quickly developed and made available to reduce its morbidity and mortality. This study aimed to describe the trends and evaluate the association of COVID-19 vaccination with indicators of morbidity and mortality due to the disease in Brazil.Methods: This was an ecological study whose unit of analysis was the time elapsed between February 16th, 2020, from the introduction of COVID-19 in Brazil and July 17th, 2021, six months after the start of vaccination in the country. From secondary databases, indicators of morbidity and mortality (incidence of hospitalization, proportion of severe cases, lethality and mortality) and vaccine coverage (doses 1, 2 or single dose) per epidemiological week (EW) and age groups were calculated (18 to 59 years and 60 years or older). Indicators of morbimortality were compared in the pre-vaccination (EW 8/2020 to EW 2/2021) and vaccination (EW 3/2021 to EW 28/2021) periods, analyzing the trends estimated using the JointPoint model and their associations using the Poisson model.Results: For individuals aged 60 years and over, during the period of COVID-19 vaccination there was a weekly trend towards a reduction in the incidence of hospitalizations (PMSV: -4.7%), severity (PMSV: -0.3%, lethality (PMSV: -2.0%) and mortality (PMSV: -2.8%); the increase in COVID-19 vaccination coverage was inversely associated with the incidence of hospitalizations (IRR: 0.969), lethality (IRR: 0.993), and mortality (IRR: 0.981). For individuals aged 18 to 59 years of age, during the period of COVID-19 vaccination there was a weekly trend towards a reduction in the incidence of hospitalizations (PMSV: -2.6%) and lethality (PMSV: -2.0%), while there was an increase in mortality (PMSV: 3.8%); the increase in COVID-19 vaccination coverage was inversely associated with the incidence of hospitalizations (IRR: 0.975) and lethality (IRR: 0.939). Conversely, it was directly associated with mortality (IRR: 1.054).Conclusions: it was demonstrated that COVID-19 vaccination had an indirect impact in reducing the morbidity and mortality trend from the disease in Brazil, especially in the elderly population, in which vaccination was prioritized and achieved greater coverage, when compared to individuals aged 18 to 59 years.