Tag: pubmed

Neural Netw. 2021 Sep 9;144:394-406. doi: 10.1016/j.neunet.2021.09.005. Online ahead of print.

ABSTRACT

Uncertainty evaluation is a core technique when deep neural networks (DNNs) are used in real-world problems. In practical applications, we often encounter unexpected samples that have not seen in the training process. Not only achieving the high-prediction accuracy but also detecting uncertain data is significant for safety-critical systems. In statistics and machine learning, Bayesian inference has been exploited for uncertainty evaluation. The Bayesian neural networks (BNNs) have recently attracted considerable attention in this context, as the DNN trained using dropout is interpreted as a Bayesian method. Based on this interpretation, several methods to calculate the Bayes predictive distribution for DNNs have been developed. Though the Monte-Carlo method called MC dropout is a popular method for uncertainty evaluation, it requires a number of repeated feed-forward calculations of DNNs with randomly sampled weight parameters. To overcome the computational issue, we propose a sampling-free method to evaluate uncertainty. Our method converts a neural network trained using dropout to the corresponding Bayesian neural network with variance propagation. Our method is available not only to feed-forward NNs but also to recurrent NNs such as LSTM. We report the computational efficiency and statistical reliability of our method in numerical experiments of language modeling using RNNs, and the out-of-distribution detection with DNNs.

PMID:34562813 | DOI:10.1016/j.neunet.2021.09.005

J Natl Black Nurses Assoc. 2021 Sep;32(1):35-40.

ABSTRACT

Nurses experience high levels of stress. In this study, functional social support and perceived stress of nurses working in secular and religious hospitals were examined. The social support model, the job demands-resources theory, and the transactional model of stress guided this study. The population that was examined was comprised of a convenience and snowballing sample of 84 registered nurses from across the United States. The data collected using the Expanded Nursing Stress Scale, the Inventory of Socially Supportive Behavior survey, and a demographic questionnaire were statistically analyzed using Pearson’s correlation and Fisher’s Test. Results showed no significant relationship between support and nurses’ stress in secular hospitals and no significant relationship between the same variables for nurses’ in religious hospitals. Findings also revealed that there was no significant difference in the compared correlations for nurses’ support and stress between the two groups. The outcomes will inform healthcare professionals about the association between nurses’ support and stress in hospitals with unique missions.

PMID:34562351

J Paediatr Child Health. 2021 Sep 25. doi: 10.1111/jpc.15748. Online ahead of print.

ABSTRACT

AIM: We aimed to investigate the influenza immunisation status of caregivers and household contacts of children with congenital heart disease (CHD) and potential barriers to vaccine uptake.

METHODS: Prospective questionnaire-based survey over two influenza seasons (2019-2020 and 2020-2021) on 161 children with CHD attending a tertiary paediatric cardiology clinic and their families. Logistic regression and factor analysis were performed to identify factors associated with influenza vaccine uptake.

RESULTS: Influenza vaccination coverage of children was 65%, whereas that of their fathers and mothers was 34% and 26%, respectively. Children with unvaccinated siblings represented 43% and those with unvaccinated adults in the household 79% of our study population. No statistically significant differences were found before and during COVID-19 pandemic on vaccine uptake. Logistic regression analysis showed that higher education level, understanding the risk of contracting the disease and vaccination status of the child determined the vaccination status of parents, regardless of their age, age of their child, severity of CHD, beliefs about vaccine safety and efficacy and risk of transmission if not vaccinated. Factor analysis revealed distinct groups among unvaccinated parents (76.3% of the variation in the responses).

CONCLUSIONS: Vaccination coverage of caregivers and household contacts of children with CHD is suboptimal. Influenza vaccination campaigns should take into consideration the specific characteristics of parental groups and target interventions accordingly to increase their vaccine uptake and indirectly protect children with CHD.

PMID:34562323 | DOI:10.1111/jpc.15748

CPT Pharmacometrics Syst Pharmacol. 2021 Sep 25. doi: 10.1002/psp4.12714. Online ahead of print.

ABSTRACT

Metaheuristics is a powerful optimization tool that is increasingly used across disciplines to tackle general purpose optimization problems. Nature-inspired metaheuristic algorithms is a subclass of metaheuristic algorithms and have been shown to be particularly flexible and useful in solving complicated optimization problems in computer science and engineering. A common practice with metaheuristics is to hybridize it with another suitably chosen algorithm for enhanced performance. This paper reviews metaheruristic algorithms and demonstrates some of its utility in tackling pharmacometric problems. Specifically, we provide three applications using one of its most celebrated members, particle swarm optimization (PSO), and show that PSO can effectively estimate parameters in complicated nonlinear mixed-effects models and to gain insights into statistical identifiability issues in a complex compartment model. In the third application, we demonstrate how to hybridize PSO with sparse grid, which is an often used technique to evaluate high dimensional integrals, to search for D-efficient designs for estimating parameters in nonlinear mixed-effects models with a count outcome. We also show the proposed hybrid algorithm outperforms its competitors when sparse grid is replaced by its competitor, adaptive gaussian quadrature to approximate the integral, or when PSO is replaced by three notable nature-inspired metaheuristic algorithms.

PMID:34562342 | DOI:10.1002/psp4.12714

J Appl Clin Med Phys. 2021 Sep 25. doi: 10.1002/acm2.13427. Online ahead of print.

ABSTRACT

PURPOSE: To demonstrate fast treatment planning feasibility of stereotactic body radiation therapy (SBRT) for centrally located lung tumors on Halcyon Linac via a previously validated knowledge-based planning (KBP) model to support offline adaptive radiotherapy.

MATERIALS/METHODS: Twenty previously treated non-coplanar volumetric-modulated arc therapy (VMAT) lung SBRT plans (c-Truebeam) on SBRT-dedicated C-arm Truebeam Linac were selected. Patients received 50 Gy in five fractions. c-Truebeam plans were re-optimized for Halcyon manually (m-Halcyon) and with KBP model (k-Halcyon). Both m-Halcyon and k-Halcyon plans were normalized for identical or better target coverage than clinical c-Truebeam plans and compared for target conformity, dose heterogeneity, dose fall-off, and dose tolerances to the organs-at-risk (OAR). Treatment delivery parameters and planning times were evaluated.

RESULTS: k-Halcyon plans were dosimetrically similar or better than m-Halcyon and c-Truebeam plans. k-Halcyon and m-Halcyon plan comparisons are presented with respect to c-Truebeam. Differences in conformity index were statistically insignificant in k-Halcyon and on average 0.02 higher (p = 0.04) in m-Halcyon plans. Gradient index was on average 0.43 (p = 0.006) lower and 0.27 (p = 0.02) higher for k-Halcyon and m-Halcyon, respectively. Maximal dose 2 cm away in any direction from target was statistically insignificant. k-Halcyon increased maximal target dose on average by 2.9 Gy (p < 0.001). Mean lung dose was on average reduced by 0.10 Gy (p = 0.004) in k-Halcyon and increased by 0.14 Gy (p < 0.001) in m-Halcyon plans. k-Halcyon plans lowered bronchial tree dose on average by 1.2 Gy. Beam-on-time (BOT) was increased by 2.85 and 1.67 min, on average for k-Halcyon and m-Halcyon, respectively. k-Halcyon plans were generated in under 30 min compared to estimated dedicated 180 ± 30 min for m-Halcyon or c-Truebeam plan.

CONCLUSION: k-Halcyon plans were generated in under 30 min with excellent plan quality. This adaptable KBP model supports high-volume clinics in the expansion or transfer of lung SBRT patients to Halcyon.

PMID:34562308 | DOI:10.1002/acm2.13427

Clin Exp Immunol. 2021 Sep 25. doi: 10.1111/cei.13665. Online ahead of print.

ABSTRACT

This large cohort study from the US Premier Healthcare Database evaluated the risk and predictors of anaphylaxis in association with intravenous immunoglobulin (IVIg) therapy in the inpatient and outpatient setting. Data were collected retrospectively (01/2009-12/2018) from 24,919 patients administered IgPro10 IVIg, median age 54 years. Immunoglobulins of interest were IgPro10 and other IVIg given before or after IgPro10. Moderate and severe anaphylaxis was identified from same-day parenteral epinephrine and IVIg use and reviews of patient record summaries. Predictors for first anaphylactic reactions associated with IVIg administration were derived from adjusted incidence rate ratios (IRR) using Poisson regression. Moderate anaphylaxis in IVIg use was rare, severe anaphylaxis very rare based on a total of 124 moderate and four non-fatal severe first anaphylactic events, incidence rate of 7.11 and 0.23/10,000 IVIg administrations respectively. Age under 18 was an independent predictor of moderate or severe anaphylactic events, adjusted IRR 2.94 (0.95-CI, 1.91-4.52) compared with those 18 years and older. First IVIg administration was a strong predictor of anaphylaxis. The IRR in those with a subsequent IVIg administration in the preceding 42 days, decreased to 0.27 (0.17-0.42) and in those effectively IVIg-naïve (no IVIg for > 42 days) to 0.76 (0.44-1.32) compared with first IVIg use. The key conclusions from this study are that the risk of anaphylaxis has progressively reduced over the last decade, from 14.87/10,000 in 2009-2010 to 4.39/10,000 IVIg administrations in 2017-2018 and is rare overall, and that the risk of anaphylaxis is increased in those aged under 18.

PMID:34562316 | DOI:10.1111/cei.13665

Health Econ. 2021 Sep 25. doi: 10.1002/hec.4408. Online ahead of print.

ABSTRACT

Cost-effectiveness analyses (CEA) are recommended to include sensitivity analyses which make a range of contextually plausible assumptions about missing data. However, with longitudinal data on, for example, patients’ health-related quality of life (HRQoL), the missingness patterns can be complicated because data are often missing both at specific timepoints (interim missingness) and following loss to follow-up. Methods to handle these complex missing data patterns have not been developed for CEA, and must recognize that data may be missing not at random, while accommodating both the correlation between costs and health outcomes and the non-normal distribution of these endpoints. We develop flexible Bayesian longitudinal models that allow the impact of interim missingness and loss to follow-up to be disentangled. This modeling framework enables studies to undertake sensitivity analyses according to various contextually plausible missing data mechanisms, jointly model costs and outcomes using appropriate distributions, and recognize the correlation among these endpoints over time. We exemplify these models in the REFLUX study in which 52% of participants had HRQoL data missing for at least one timepoint over the 5-year follow-up period. We provide guidance for sensitivity analyses and accompanying code to help future studies handle these complex forms of missing data.

PMID:34562295 | DOI:10.1002/hec.4408

Nurs Inq. 2021 Sep 25:e12465. doi: 10.1111/nin.12465. Online ahead of print.

ABSTRACT

One challenge for those reading methodological debates in low consensus fields is determining the outcome when participants do not share standards. When parties to a debate do not agree on the standards to be used in assessing their arguments (i.e., quality), it may be useful to ask first if parties’ contributions meet their own expectations (i.e., integrity). Most protocols for review of qualitative research specify some form of quality assessment. These protocols normally require some test of internal coherence. Coherence is also relevant when describing the match between a rebuttal and the argument it answers. In 2019, Nursing Inquiry published a critique and rebuttal of the methods used by the Joanna Briggs Institute. In this essay, we attempted to use the Joanna Briggs Institute’s own quality assessment standards to assess their rebuttal of this fundamental critique. We found it possible to use the Joanna Briggs Institute’s own quality assessment standards to assess this rebuttal, and we found that JBI’s rebuttal did not meet their own standards.

PMID:34562297 | DOI:10.1111/nin.12465

Diabetes Ther. 2021 Sep 25. doi: 10.1007/s13300-021-01141-8. Online ahead of print.

ABSTRACT

INTRODUCTION: Once-weekly (OW) semaglutide was associated with clinically relevant improvements in glycaemic control and body weight versus comparators in the SUSTAIN randomised controlled trials (RCTs). SURE UK, which is one of a series of individual studies that comprise the SURE programme, evaluated the use of OW semaglutide in a real-world patient population with type 2 diabetes (T2D) in the UK.

METHODS: In this prospective, observational study, adults (≥ 18 years) with ≥ 1 documented glycated haemoglobin (HbA_1c) value ≤ 12 weeks before semaglutide initiation were enrolled. The primary endpoint was change in HbA_1c from baseline to end of study (EOS; ~ 30 weeks, although due to the COVID-19 pandemic, visits up to week 52 were permitted). Secondary endpoints included change in body weight, waist circumference and patient-reported outcomes (PROs). Physicians were to report all episodes of documented or severe hypoglycaemia, fatal events, serious adverse drug reactions, pregnancies and adverse events (AEs) in foetuses/newborn infants; other AEs during the study period could be reported on a voluntary basis.

RESULT: The estimated mean change in HbA_1c from baseline to EOS was – 16.3 mmol/mol [95% confidence interval (CI): – 18.22, – 14.37] (- 1.5%-points [95% CI – 1.67, – 1.31]; p < 0.0001) among the 171 enrolled patients who completed the study on treatment. Mean body weight change was – 5.8 kg (95% CI – 6.75, – 4.94; p < 0.0001). Sensitivity analyses showed similar results. Improvements were also observed in other secondary endpoints, including PROs. No new safety concerns were identified with semaglutide treatment.

CONCLUSION: Patients receiving OW semaglutide experienced statistically significant and clinically relevant reductions from baseline in HbA_1c and body weight. These results are in line with those of the SUSTAIN RCTs and support the use of OW semaglutide in routine clinical practice in adults with T2D in the UK.

TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT03876015.

PMID:34562237 | DOI:10.1007/s13300-021-01141-8

Int J Cancer. 2021 Sep 25. doi: 10.1002/ijc.33823. Online ahead of print.

ABSTRACT

Treatment options for metastatic osteosarcomas are scarce. Following failure of standard first line therapy, patients who relapse present a challenging treatment dilemma, and have a poor prognosis. Surgical removal of all metastases is essential. A retrospective analysis of patients with metastatic osteosarcomas was conducted in 15 French Sarcoma Group centers. From January 2009 to December 2018, we identified 120 adult patients; 36 with synchronous and 84 with metachronous metastases with 74 males and 46 females. Mean age was 30 years (18-53). Metastatic sites were lung, bone and other in 91, 11 and 24 patients respectively. Mean time to first metachronous metastases was 22 months (4-97). All patients except 13 (10.8%) with metachronous metastases received a first line systemic treatment for relapse, and 39 patients (32.5%) were included in a clinical trial. Eighty-one patients (67.5%) had local treatment of distant metastases. Median progression free survival (PFS) and overall survival (OS) were 5.5 (95%CI 4.6-6.4) and 20.5 months (95%CI 13.2-27.7) respectively for the overall group. In multivariate analysis; > 5 metastases, time to 1^st metastases < 24 months, were statistically significant negative prognostic factors for OS and PFS (p= 0.002, ≤0.001 and p=0.006, ≤0.001 respectively). Surgery of metastases was associated with better prognosis on OS and PFS (p=0.001 and 0.037 respectively). The presence of bone metastases was a negative prognostic factor on OS but not on PFS (p=0.021). In reference sarcoma centers, relapsed osteosarcoma patients with > 1 metastasis commonly receive more than one line of systemic therapy, and are included in clinical trial if available. This article is protected by copyright. All rights reserved.

PMID:34562271 | DOI:10.1002/ijc.33823