generalised estimating equations
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2021 ◽  
pp. tobaccocontrol-2021-056985
Author(s):  
Jennifer Pearson ◽  
Ollie Ganz ◽  
Pamela Ohman-Strickland ◽  
Olivia A Wackowski

IntroductionPeople believe that cigarettes using ‘organic,’ ‘additive-free’ or similar descriptors are less harmful than other cigarettes. Natural American Spirit (NAS) is the most popular US cigarette brand using these descriptors. This cohort study describes changes in US smokers’ odds of preferring NAS and changes in NAS smokers’ odds of believing their brand might be less harmful than other brands.MethodsData come from four waves (2013–2018) of the Population Assessment of Tobacco and Health (PATH) Study. Generalised estimating equations produced population-averaged estimates of relationships between (1) NAS brand preference and wave and (2) belief that one’s own brand might be less harmful than other brands, wave and NAS brand preference. Models tested interactions by age group and sexual minority status.ResultsThe odds that smokers preferred NAS increased by 60% in W4 relative to W1. Disproportionate preference by younger adult and sexual minority smokers was observed. The odds that NAS smokers believed their own brand might be less harmful decreased by 50% between W1 and W4, but this perception was still 16 times higher for NAS compared with non-NAS smokers. Given the increasing preference for NAS, there was no significant change in the absolute number of NAS smokers who believed their own brand might be less harmful (W1: 562 122 (95% CI 435 190 to 689 055) vs W4: 580 378 (95% CI 441 069 to 719 689)).ConclusionsBoth brand popularity and concentration of brand-related harm perceptions are important for understanding population impact of changes in cigarette marketing.


2021 ◽  
Vol 9 (10) ◽  
pp. 1081
Author(s):  
Cynthia Barile ◽  
Simon Berrow ◽  
Joanne O’Brien

Cuvier’s and Sowerby’s beaked whales occur year-round in western Irish waters, yet remain some of the most poorly understood cetaceans in the area. Considering the importance of the area for anthropogenic activities and the sensitivity of beaked whales to noise, understanding their ecology is essential to minimise potential overlaps. To this end, fixed bottom-mounted autonomous acoustic recorders were deployed at 10 stations over four recording periods spanning from May 2015 to November 2016. Acoustic data were collected over 1934 cumulative days, for a total of 7942 h of recordings. To model the probability of presence of Cuvier’s and Sowerby’s beaked whales in the area as a function of oceanographic predictors, we used Generalised Additive Models, fitted with Generalised Estimating Equations to deal with temporal autocorrelation. To reflect prey availability, oceanographic variables acting as proxies of primary productivity and prey aggregation processes such as upwelling events and thermal fronts were selected. Our results demonstrated that oceanographic variables significantly contributed to the occurrence of Cuvier’s and Sowerby’s beaked whales (p-values between <0.001 and <0.05). The species showed similar preferences, with the exception of sdSST. The inclusion of a parameter accounting for the recorders location confirmed the existence of a latitudinal partitioning for those species in the area. This study provides a point of comparison for future research and represents an important step towards a better understanding of those elusive species.


Author(s):  
Thomas E. Dorner ◽  
Ellenor Mittendorfer-Rutz ◽  
Magnus Helgesson ◽  
Tea Lallukka ◽  
Jenni Ervasti ◽  
...  

Low back pain (LBP) patients undergoing lumbar spine decompression surgery (LSDS) often suffer from multi-comorbidity and experience high work disability. This study aimed to identify diagnosis-specific work disability patterns in all LBP-patients before and after LSDS during 2008–2010, that were aged 19–60 years and living in Sweden (n = 10,800) and compare these patterns to LBP-patients without LSDS (n = 109,179), and to matched individuals without LBP (n = 472,191). Work disability days (long-term sickness absence (LTSA), disability pension (DP)) during the three years before to three years after the cohort’s entry date were identified by generalised estimating equations. LBP-patients undergoing LSDS had higher overall work disability during the three years following surgery (LTSA: 23.6%, DP: 6.3%) than LBP-patients without LSDS (LTSA: 19.5%, DP: 5.9%), and those without LBP (LTSA: 7.9%, DP: 1.7%). Among patients undergoing LSDS, the prevalence of work disability due to dorsopathies increased from 20 days three years before surgery to 70 days in the year after and attenuated to 30 days in the third year following surgery. Work disability for other diagnoses remained stable at a low level in this group (<10 days annually). LBP-patients undergoing LSDS have an unfavourable long-term work disability prognosis, primarily due to dorsopathies. Decompression surgery seemed to restrict further inclines in work disability in the long run.


Nutrients ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 2911
Author(s):  
Samuel J. Dicken ◽  
John J. Mitchell ◽  
Jessica Newberry Le Newberry Le Vay ◽  
Emma Beard ◽  
Dimitra Kale ◽  
...  

COVID-19-related restrictions impacted weight and weight-related factors during the initial months of the pandemic. However, longitudinal analyses are scarce. An online, longitudinal study was conducted among self-selected UK adults (n = 1818), involving three surveys (May–June, August–September, November–December 2020), covering anthropometric, sociodemographic, COVID-19-related and behavioural measures. Data were analysed using generalised estimating equations. Self-reported average weight/body mass index (BMI) significantly increased between the May–June period and the August–September period (74.95 to 75.33 kg/26.22 kg/m2 to 26.36kg/m2, p < 0.001, respectively), and then significantly decreased to November–December (to 75.06 kg/26.27 kg/m2, p < 0.01), comparable to May–June levels (p = 0.274/0.204). However, there was great interindividual variation, 37.0%/26.7% increased (average 3.64 kg (95% confidence interval: 3.32, 3.97)/1.64 kg/m2 (1.49, 1.79)), and 34.5%/26.3% decreased (average 3.59 kg (3.34, 3.85)/1.53 kg/m2 (1.42, 1.63)) weight/BMI between May–June and November–December. Weight/BMI increase was significantly negatively associated with initial BMI, and positively associated with monthly high fat, salt and sugar (HFSS) snacks intake and alcohol consumption, and for BMI only, older age. Associations were time-varying; lower initial BMI, higher HFSS snacks intake and high-risk alcohol consumption were associated with maintaining weight/BMI increases between August–September and November–December. The average weight/BMI of UK adults fluctuated between May–June and November–December 2020. However, the substantial interindividual variation in weight/BMI trajectories indicates long-term health impacts from the pandemic, associated with food and alcohol consumption.


2021 ◽  
Author(s):  
Samuel James Dicken ◽  
John Joseph Mitchell ◽  
Jessica Newberry Le Vay ◽  
Emma Beard ◽  
Dimitra Kale ◽  
...  

Background COVID-19-related restrictions impacted weight and weight-related factors during the initial months of the pandemic. However, longitudinal analyses are scarce. Methods An online, longitudinal study was conducted among self-selected UK adults (n=1,818), involving three surveys during 2020 (May-June, August-September, November-December), covering height, weight and sociodemographic, COVID-19-related and behavioural measures. Data were analysed using generalised estimating equations. Results Self-reported average weight and body mass index (BMI) significantly increased from May-June to August-September (74.95kg to 75.33kg, 26.22kg/m2 to 26.36kg/m2, both p<0.001), and then significantly decreased to November-December (to 75.06kg, 26.27kg/m2, both p<0.01), comparable to May-June levels (p=0.274/0.204). However, there was great interindividual variation, with 37.0%/26.7% reporting an increase and 34.5%/26.3% reporting a decrease in weight/BMI greater than 0.5kg/0.5kg/m2, respectively from May-June to November-December. The average weight/BMI increase was 3.64kg (95% confidence interval: 3.32,3.97)/1.64kg/m2 (1.49,1.79), and the average weight/BMI decrease was 3.59kg (3.34,3.85)/1.53kg/m2 (1.42,1.63). In fully adjusted models, increase in weight/BMI across surveys was significantly negatively associated with initial BMI, and positively associated with monthly high fat, salt and sugar (HFSS) snacks intake and alcohol consumption, and for BMI only, older age. However, associations were time-varying, such that lower initial BMI, higher HFSS snacks intake and high-risk alcohol consumption were associated with maintenance of increased weight/BMI from August-September to November-December. Conclusion The average weight/BMI of UK adults increased during the early pandemic months, before returning to baseline levels in November-December 2020. However, this masks substantial interindividual variation in weight/BMI trajectories, indicating vulnerabilities associated with changes in food and alcohol consumption throughout the pandemic.


BJPsych Open ◽  
2021 ◽  
Vol 7 (4) ◽  
Author(s):  
Alastair Macdonald ◽  
Dimitrios Adamis ◽  
Matthew Broadbent ◽  
Tom Craig ◽  
Rob Stewart ◽  
...  

Background People with schizophrenia have shortened lives. This excess mortality seems to be related to physical health conditions that may be amenable to better primary and secondary prevention. Better continuity of care may enhance such interventions as well as help prevent death by self-injury. Aims We set out to examine the relationship between the continuity of care of patients with schizophrenia, their mortality and cause of death. Method Pseudoanonymised community data from 5551 people with schizophrenia presenting over 11 years were examined for changes in continuity of care using the numbers of community teams caring for them and the Modified Modified Continuity Index. These and demographic variables were related to death certifications of physical illness from the Office of National Statistics and mortal self-injury from clinical data. Data were analysed using generalised estimating equations. Results We found no independent relationship between levels of continuity of care and overall mortality. However, lower levels of relationship continuity were significantly and independently related to death by self-injury. Conclusions We found no evidence that continuity of care is important in the prevention of physical causes of death in schizophrenia. However, there is evidence that declining relationship continuity of care has an independent effect on deaths as a result of self-injury. We suggest that there should be more attention focused on the improvement of continuity of care for these patients.


PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0251194
Author(s):  
Heidi Seibold ◽  
Severin Czerny ◽  
Siona Decke ◽  
Roman Dieterle ◽  
Thomas Eder ◽  
...  

Computational reproducibility is a corner stone for sound and credible research. Especially in complex statistical analyses—such as the analysis of longitudinal data—reproducing results is far from simple, especially if no source code is available. In this work we aimed to reproduce analyses of longitudinal data of 11 articles published in PLOS ONE. Inclusion criteria were the availability of data and author consent. We investigated the types of methods and software used and whether we were able to reproduce the data analysis using open source software. Most articles provided overview tables and simple visualisations. Generalised Estimating Equations (GEEs) were the most popular statistical models among the selected articles. Only one article used open source software and only one published part of the analysis code. Replication was difficult in most cases and required reverse engineering of results or contacting the authors. For three articles we were not able to reproduce the results, for another two only parts of them. For all but two articles we had to contact the authors to be able to reproduce the results. Our main learning is that reproducing papers is difficult if no code is supplied and leads to a high burden for those conducting the reproductions. Open data policies in journals are good, but to truly boost reproducibility we suggest adding open code policies.


2021 ◽  
pp. bjophthalmol-2020-318674
Author(s):  
Carla Lanca ◽  
Chen Hsin Sun ◽  
Rachel Chong ◽  
Yee Ling Wong ◽  
Monisha Esther Nongpiur ◽  
...  

AimsTo characterise the association between visual field (VF) defects and myopic macular degeneration (MMD) in highly myopic adults without glaucoma.MethodsParticipants (n=106; 181 eyes) with high myopia (HM; spherical equivalent ≤−5.0 D or axial length (AL) ≥26 mm), after excluding glaucoma and glaucoma suspects, from the Singapore Epidemiology of Eye Diseases-HM study were included in this cross-sectional study. Humphrey VF (central 24–2 threshold), cup-disc ratio (CDR) and intraocular pressure (IOP) measurements were performed. Mean deviation (MD) and pattern SD (PSD), VF defects (normal or abnormal; p<0.05 in ≥3 non-edge contiguous locations) and pattern (eg, generalised sensitivity loss) were analysed. MMD presence was diagnosed from fundus photographs. Generalised estimating equations were used for analysing factors (MD, PSD, VF defects, CDR and IOP) associated with MMD.ResultsMean age was 55.4±9.9 years and 51.9% were women (AL=26.7±1.1 mm). MMD eyes had lower MD (−3.8±2.9 dB vs −1.1±1.4 dB) and higher PSD (2.8±1.7 dB vs 1.7±0.6 dB). A higher percentage of MMD eyes (n=48) had abnormal VF (62.5% vs 28.6%; p<0.001) compared with no MMD (n=133 eyes). VF pattern in MMD eyes was significantly different from eyes without MMD (p=0.001) with greater generalised sensitivity loss (53.3% vs 10.5%) and arcuate defects (16.7% vs 10.5%). In multivariate analyses, MD (OR=1.52) and PSD (OR=1.67) were significantly (p=0.003) associated with MMD, but VF defects were not associated with MMD.ConclusionHighly myopic adults with MMD may have VF loss when compared with highly myopic patients without MMD even in adults without glaucoma.


2021 ◽  
pp. bjophthalmol-2021-318918
Author(s):  
Mijie Li ◽  
Carla Lanca ◽  
Chuen-Seng Tan ◽  
Li-Lian Foo ◽  
Chen-Hsin Sun ◽  
...  

Background/aimsTo evaluate the association of reported time outdoors and light exposure patterns with myopia among children aged 9 years from the Growing Up in Singapore Towards Healthy Outcomes birth cohort.MethodsWe assessed reported time outdoors (min/day), light exposure patterns and outdoor activities of children aged 9 years (n=483) with a questionnaire, the FitSight watch and a 7-day activity diary. Light levels, the duration, timing and frequency of light exposure were assessed. Cycloplegic spherical equivalent (SE), myopia (SE≤−0.5 D) and axial length (AL) of paired eyes were analysed using generalised estimating equations.ResultsIn this study, 483 (966 eyes) multiethnic children (50.0% boys, 59.8% Chinese, 42.2% myopic) were included. Reported time outdoors (mean±SD) was 100±93 min/day, and average light levels were 458±228 lux. Of the total duration children spent at light levels of ≥1000 lux (37±19 min/day), 76% were spent below 5000 lux. Peak light exposure occurred at mid-day. Children had 1.7±1.0 light exposure episodes/day. Common outdoor activities were walks, neighbourhood play and swimming. Greater reported time outdoors was associated with lower odds of myopia (OR=0.82, 95% CI 0.70 to 0.95/hour increase daily; p=0.009). Light levels, timing and frequency of light exposures were not associated with myopia, SE or AL (p>0.05).ConclusionReported time outdoors, light levels and number of light exposure episodes were low among Singaporean children aged 9 years. Reported time outdoors was protective against myopia but not light levels or specific light measures. A multipronged approach to increase time outdoors is recommended in the combat against the myopia epidemic.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lynleigh Evans ◽  
Yiren Liu ◽  
Brendan Donovan ◽  
Terence Kwan ◽  
Karen Byth ◽  
...  

Abstract Background While multidisciplinary teams (MDTs) are now considered an essential part of cancer care decision-making, how they perform varies widely. The authors hypothesised that a comprehensive, multipronged improvement program, and associated annual member survey, could strengthen MDT performance across a whole cancer service. Methods The study comprised the introduction of a structured program, the Tumour Program Strengthening Initiative (TPSI) linked with an annual survey of member’s perceptions of their performance. Three iterations of the survey have been completed (2017, 2018 and 2019). Generalised estimating equations (GEEs) were used to test for a difference in the proportion of positive survey responses between 2017 and 2019 adjusted for team clustering. Results Twelve teams participated in TPSI. One hundred twenty-nine, 118 and 146 members completed the survey in 2017, 2018 and 2019, respectively. Of the 17 questions that were asked in all three years, nine showed significant improvement and, of these, five were highly significant. Documenting consensus, developing Terms of Reference (TORs), establishing referral criteria and referring to clinical practice guidelines showed most improvement. Questions related to patient considerations, professional development and quality improvement (QI) activities showed no significant change. Conclusions TPSI resulted in sustained and significant improvement. The MDT survey not only allowed MDT members to identify their strengths and weaknesses but also provided insights for management to flag priority areas for further support. Overall program improvement reflected the strengthening of the weakest teams as well as further improvement in highly performing MDTs. Importantly, the initiative has the potential to achieve behaviour change amongst clinicians.


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