multilevel regression
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2022 ◽  
Vol 8 ◽  
Author(s):  
Etienne Rouby ◽  
Laurent Dubroca ◽  
Thomas Cloâtre ◽  
Sebastien Demanèche ◽  
Mathieu Genu ◽  
...  

Marine megafauna plays an important functional role in marine ecosystems as top predators but are threatened by a wide range of anthropogenic activities. Bycatch, the incidental capture of non-targeted species in commercial and recreational fisheries, is of particular concern for small cetacean species, such as dolphins and porpoises. In the North-East Atlantic, common dolphin (Delphinus delphis, Linné 1758) bycatch has been increasing and associated with large numbers of animals stranding during winter on the French Atlantic seashore since at least 2017. However, uncertainties around the true magnitude of common dolphin bycatch and the fisheries involved have led to delays in the implementation of mitigation measures. Current data collection on dolphin bycatch in France is with non-dedicated observers deployed on vessels for the purpose of national fisheries sampling programmes. These data cannot be assumed representative of the whole fisheries' bycatch events. This feature makes it difficult to use classic ratio estimators since they require a truly randomised sample of the fishery by dedicated observers. We applied a newly developed approach, regularised multilevel regression with post-stratification, to estimate total bycatch from unrepresentative samples and total fishing effort. The latter is needed for post-stratification and the former is analysed in a Bayesian framework with multilevel regression to regularise and better predict bycatch risk. We estimated the number of bycaught dolphins for each week and 10 International Council for the Exploration of the Sea (ICES) divisions from 2004 to 2020 by estimating jointly bycatch risk, haul duration, and the number of hauls per days at sea (DaS). Bycatch risk in pair trawlers flying the French flag was the highest in winter 2017 and 2019 and was associated with the longest haul durations. ICES divisions 8.a and 8.b (shelf part of the Bay of Biscay) were estimated to have the highest common dolphin bycatch. Our results were consistent with independent estimates of common dolphin bycatch from strandings. Our method show cases how non-representative observer data can nevertheless be analysed to estimate fishing duration, bycatch risk and, ultimately, the number of bycaught dolphins. These weekly-estimates improve upon current knowledge of the nature of common dolphin bycatch and can be used to inform management and policy decisions at a finer spatio-temporal scale than has been possible to date. Our results suggest that limiting haul duration, especially in winter, could serve as an effective mitigation strategy.


2022 ◽  
Vol 104-B (1) ◽  
pp. 59-67
Author(s):  
Sarah R. Kingsbury ◽  
Lindsay K. Smith ◽  
Farag Shuweihdi ◽  
Robert West ◽  
Carolyn Czoski Murray ◽  
...  

Aims The aim of this study was to conduct a cross-sectional, observational cohort study of patients presenting for revision of a total hip, or total or unicompartmental knee arthroplasty, to understand current routes to revision surgery and explore differences in symptoms, healthcare use, reason for revision, and the revision surgery (surgical time, components, length of stay) between patients having regular follow-up and those without. Methods Data were collected from participants and medical records for the 12 months prior to revision. Patients with previous revision, metal-on-metal articulations, or hip hemiarthroplasty were excluded. Participants were retrospectively classified as ‘Planned’ or ‘Unplanned’ revision. Multilevel regression and propensity score matching were used to compare the two groups. Results Data were analyzed from 568 patients, recruited in 38 UK secondary care sites between October 2017 and October 2018 (43.5% male; mean (SD) age 71.86 years (9.93); 305 hips, 263 knees). No significant inclusion differences were identified between the two groups. For hip revision, time to revision > ten years (odds ratio (OR) 3.804, 95% confidence interval (CI) (1.353 to 10.694), p = 0.011), periprosthetic fracture (OR 20.309, 95% CI (4.574 to 90.179), p < 0.001), and dislocation (OR 12.953, 95% CI (4.014 to 41.794), p < 0.001), were associated with unplanned revision. For knee, there were no associations with route to revision. Revision after ten years was more likely for those who were younger at primary surgery, regardless of route to revision. No significant differences in cost outcomes, length of surgery time, and access to a health professional in the year prior to revision were found between the two groups. When periprosthetic fractures, dislocations, and infections were excluded, healthcare use was significantly higher in the unplanned revision group. Conclusion Differences between characteristics for patients presenting for planned and unplanned revision are minimal. Although there was greater healthcare use in those having unplanned revision, it appears unlikely that routine orthopaedic review would have detected many of these issues. It may be safe to disinvest in standard follow-up provided there is rapid access to orthopaedic review. Cite this article: Bone Joint J 2022;104-B(1):59–67.


PAIN Reports ◽  
2022 ◽  
Vol 7 (1) ◽  
pp. e963
Author(s):  
Belay B. Yimer ◽  
David M. Schultz ◽  
Anna L. Beukenhorst ◽  
Mark Lunt ◽  
Huai L. Pisaniello ◽  
...  

2021 ◽  
Vol 27 (4) ◽  
pp. 72-98
Author(s):  
Zulfiya Ibragimova ◽  
Marina Frants

This study measures the impact of spatial factors on the educational achievements of Russian students. According to the theory of equal opportunities, individual achievements depend on two groups of determinants: uncontrollable circumstances and one’s own efforts. Inequality of achievements produced by inequality of effort is treated as ethically acceptable, while inequality arising from circumstances is unfair and therefore must be compensated. The research is based on the data of the International Program for the Assessment of Educational Achievements of Students (PISA), wave 2018. Multilevel regression modeling was applied. A two-level model was used, in which the first level is that of the student, while the second level is regional. The calculations showed that anywhere from 14 to 16% of the variance in Russian students’ academic achievements is attributed to interregional irregularities. We learned that controlling for socio-economic status, lack of staff and material support in the school, type of area in which the school is located, and gender of the student make it possible to slightly reduce the role of regional differences, though it still remained significant. To a certain extent the impact of regional factor can be explained by variations in the influence of family background, school characteristics and gender across regions. The estimation of regional random effects allowed for identifying both the leaders and the outsiders in terms of the availability and quality of school education. Calculations have shown that the leaders and outsiders are practically the same in regards to all three areas of literacy.


2021 ◽  
Vol 12 ◽  
Author(s):  
Simple F. Kothari ◽  
Gustavo G. Nascimento ◽  
Mille B. Jakobsen ◽  
Jørgen F. Nielsen ◽  
Mohit Kothari

Objective: To investigate the effectiveness of an existing standard oral care program (SOCP) and factors associated with it during hospitalization in individuals with acquired brain injury (ABI).Material and Methods: A total of 61 individuals underwent a SOCP for 4 weeks in a longitudinal observational study. Rapidly noticeable changes in oral health were evaluated by performing plaque, calculus, bleeding on probing (BOP) and bedside oral examination (BOE) at weeks 1 and 5. Individuals' brushing habits, eating difficulties, and the onset of pneumonia were retrieved from their medical records. Association between oral-health outcomes to systemic variables were investigated through multilevel regression models.Results: Dental plaque (P = 0.01) and total BOE score (P &lt; 0.05) decreased over time but not the proportion of dental calculus (P = 0.30), BOP (P = 0.06), and tooth brushing frequency (P = 0.06). Reduction in plaque and BOE over time were negatively associated with higher periodontitis scores at baseline (coef. −6.8; −1.0), respectively, which in turn were associated with an increased proportion of BOP (coef. ≈ 15.0). An increased proportion of calculus was associated with eating difficulties (coef. 2.3) and the onset of pneumonia (coef. 6.2).Conclusions: Nursing care has been fundamental in improving oral health, especially reducing dental plaque and BOE scores. However, our findings indicate a need for improving the existing SOCP through academic-clinical partnerships.Clinical Relevance: Early introduction of oral care program to brain-injured individuals is beneficial in reducing plaque accumulation and improving oral health.


2021 ◽  
Author(s):  
Yasin Altinisik ◽  
Caspar J. Van Lissa ◽  
Herbert Hoijtink

In the social and behavioral sciences, it is often not interesting to evaluate the null hypothesis by means of a p-value. Researchers are often more interested in quantifying the evidence in the data (as opposed to using p-values) with respect to their own expectationsrepresented by equality and/or inequality constrained hypotheses (as opposed to the null hypothesis). This article proposes an Akaike-type information criterion (AIC; Akaike, 1973, 1974) called the generalized order-restricted information criterion approximation (GORICA) that evaluates (in)equality constrained hypotheses under a very broad range of statistical models. The results of five simulation studies provide empirical evidence showing that the performance of the GORICA on selecting the best hypothesis out of a set of (in)equality constrained hypotheses is convincing. To illustrate the use of the GORICA, the expectations of researchers are investigated in a logistic regression, multilevel regression, and structural equation model.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Edward Kwabena Ameyaw ◽  
Linus Baatiema ◽  
Bright Opoku Ahinkorah ◽  
Abdul-Aziz Seidu ◽  
Jerry Paul Ninnoni ◽  
...  

Abstract Background To obviate malaria and other healthcare costs and enhance healthcare utilization, the government of Ghana introduced the National Health Insurance Scheme (NHIS) in 2005. Nonetheless, there is dearth of empirical evidence on Ghanaian women’s knowledge about whether malaria treatment is covered by the NHIS or not. The current study, therefore, investigated factors associated with knowledge of malaria treatment with the NHIS among women aged 15-49 in Ghana. Methods The study is a secondary analysis of data from women respondents in the 2014 Ghana Demographic and Health Survey. A total of 2,560 women participated in this study. Descriptive computation of the weighted proportion of women who knew that malaria is covered by NHIS was conducted at 95% confidence interval (CI). A multilevel logistic regression analyses was carried out with Stata’s MLwinN package version 3.05. We declared significance at 5% alpha. Findings from the models were reported as adjusted odds ratios (aOR) and credible intervals (CrIs). Results In all, 81.0% of Ghanaian women included in the study knew that NHIS covers malaria treatment. Women aged 45-49 had higher odds of knowing that NHIS covers malaria relative to those aged 15-19 age category [aOR=1.5;95%crl=1.2-2.1]. Women with higher education (post-secondary) had higher odds of knowing that NHIS covers malaria treatment compared with women who had no formal education [aOR=1.6;95%Crl=1.2-2.0]. Richest women were more likely to know that NHIS covers malaria treatment compared to the poorest women [aOR=1.3;95%Crl=1.2-1.7]. Women who had subscribed to the NHIS were more likely to report that NHIS covers malaria treatment [aOR=1.5;95%Crl=1.2-1.8]. The study revealed that the variance in the tendency for a woman to be aware that NHIS covers malaria treatment is attributable to 10.8% community level factors. Conclusion This study has shown that individual, community and regional level factors affect women’s knowledge on whether NHIS covers malaria treatment or not. As knowledge that malaria treatment is covered by NHIS may increase use of malaria prevention and treatment services in health facilities, we recommend that the Ghana Health Service intensifies community level education and awareness creation efforts, targeted at women among whom awareness levels are currently low.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kai Man Alexander Ho ◽  
Hywel Davies ◽  
Ruth Epstein ◽  
Paul Bassett ◽  
Áine Hogan ◽  
...  

AbstractCOVID-19 has restricted singing in communal worship. We sought to understand variations in droplet transmission and the impact of wearing face masks. Using rapid laser planar imaging, we measured droplets while participants exhaled, said ‘hello’ or ‘snake’, sang a note or ‘Happy Birthday’, with and without surgical face masks. We measured mean velocity magnitude (MVM), time averaged droplet number (TADN) and maximum droplet number (MDN). Multilevel regression models were used. In 20 participants, sound intensity was 71 dB for speaking and 85 dB for singing (p < 0.001). MVM was similar for all tasks with no clear hierarchy between vocal tasks or people and > 85% reduction wearing face masks. Droplet transmission varied widely, particularly for singing. Masks decreased TADN by 99% (p < 0.001) and MDN by 98% (p < 0.001) for singing and 86–97% for other tasks. Masks reduced variance by up to 48%. When wearing a mask, neither singing task transmitted more droplets than exhaling. In conclusion, wide variation exists for droplet production. This significantly reduced when wearing face masks. Singing during religious worship wearing a face mask appears as safe as exhaling or talking. This has implications for UK public health guidance during the COVID-19 pandemic.


2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. 93-93
Author(s):  
J Jill Suitor ◽  
Megan Gilligan ◽  
Catherine Stepniak ◽  
Yifei Hou ◽  
Robert Frase

Abstract The deaths of family members constitute one of the most serious negative life events experienced in adulthood. The impact of these losses on psychological well-being may differ considerably by the structural relationship between the deceased and the survivors, and by the genders of both family members; however, few studies have been able to explore these variations by generation, gender, and time since death. In this paper, we use mixed-methods data to explore how depressive symptoms are affected differentially in adulthood by the deaths of mothers, fathers, and siblings, as well as by the gender of survivors. We address these questions using data collected from approximately 600 adult children nested within 250 later-life families, in which approximately 55% experienced the death of at least one parent and 15% experienced the death of a sibling in the previous decade. Preliminary multilevel regression analyses showed that deaths of siblings predicted sisters’ but not brothers’ depressive symptoms. In the case of parents, only mothers’ deaths were found to predict daughters’ depressive symptoms, whereas neither parents’ deaths predicted sons’ well-being. Further, these patterns differed little by time since death. Qualitative data revealed that women were more likely to report that both their mothers’ and siblings’ deaths had led to higher conflict within the sibling network, which previous research has shown predicts psychological well-being. Taken together, these findings demonstrate the salient role of gender in shaping well-being in the face of events of deaths of parents and siblings in adulthood.


BMJ Open ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. e051044
Author(s):  
Katarina Åsberg ◽  
Oskar Lundgren ◽  
Hanna Henriksson ◽  
Pontus Henriksson ◽  
Preben Bendtsen ◽  
...  

IntroductionThe time during which many attend college or university is an important period for developing health behaviours, with potentially major implications for future health. Therefore, it is concerning that many Swedish students excessively consume alcohol, have unhealthy diets, are not physical active and smoke. The potential of digital interventions which integrate support for change of all of these behaviours is largely unexplored, as are the dismantled effects of the individual components that make up digital lifestyle behaviour interventions.Methods and analysisA factorial randomised trial (six factors with two levels each) will be employed to estimate the effects of the components of a novel mHealth multiple lifestyle intervention on alcohol consumption, diet, physical activity and smoking among Swedish college and university students. A Bayesian group sequential design will be employed to periodically make decisions to continue or stop recruitment, with simulations suggesting that between 1500 and 2500 participants will be required. Multilevel regression models will be used to analyse behavioural outcomes collected at 2 and 4 months postrandomisation.Ethics and disseminationThe study was approved by the Swedish Ethical Review Authority on 2020-12-15 (Dnr 2020-05496). The main concern is the opportunity cost if the intervention is found to only have small effects. However, considering the lack of a generally available evidence-based multiple lifestyle behaviour support to university and college students, this risk was deemed acceptable given the potential benefits from the study.Recruitment will begin in March 2021, and it is expected that recruitment will last no more than 24 months. A final data set will, therefore, be available in July 2023, and findings will be reported no later than December 2023.Trial registration numberISRCTN23310640; Pre-results.


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