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Book ; Online: Extended data

Elizabeth Williamson

Codelist details for risk prediction protocol for COVID-19 related death

2020

Abstract: On March 11th 2020, the World Health Organization characterised COVID-19 as a pandemic. Responses to containing the spread of the virus have relied heavily on policies involving restricting contact between people. Evolving policies regarding shielding ... ...

Abstract	On March 11th 2020, the World Health Organization characterised COVID-19 as a pandemic. Responses to containing the spread of the virus have relied heavily on policies involving restricting contact between people. Evolving policies regarding shielding and individual choices about restricting social contact will rely heavily on perceived risk of poor outcomes from COVID-19. In order to make informed decisions, both individual and collective, good predictive models are required. For outcomes related to an infectious disease, the performance of any risk prediction model will depend heavily on the underlying prevalence of infection in the population of interest. Incorporating measures of how this changes over time may result in important improvements in prediction model performance. This document contains extended data (details of codelists used) for a protocol, conditionally accepted at Wellcome Open Research, reporting details of a planned study to explore the extent to which incorporating time-varying measures of infection burden over time improves the quality of risk prediction models for COVID-19 death in a large population of adult patients in England.
Keywords	COVID-19 ; risk prediction ; mortality ; infectious disease ; statistical methodology ; covid19
Subject code	310
Publishing date	2020-10-08
Publishing country	eu
Document type	Book ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: An evaluation of inverse probability weighting using the propensity score for baseline covariate adjustment in smaller population randomised controlled trials with a continuous outcome

Hanaya Raad / Victoria Cornelius / Susan Chan / Elizabeth Williamson / Suzie Cro

BMC Medical Research Methodology, Vol 20, Iss 1, Pp 1-

2020 Volume 12

Abstract: Abstract Background It is important to estimate the treatment effect of interest accurately and precisely within the analysis of randomised controlled trials. One way to increase precision in the estimate and thus improve the power for randomised trials ... ...

Abstract	Abstract Background It is important to estimate the treatment effect of interest accurately and precisely within the analysis of randomised controlled trials. One way to increase precision in the estimate and thus improve the power for randomised trials with continuous outcomes is through adjustment for pre-specified prognostic baseline covariates. Typically covariate adjustment is conducted using regression analysis, however recently, Inverse Probability of Treatment Weighting (IPTW) using the propensity score has been proposed as an alternative method. For a continuous outcome it has been shown that the IPTW estimator has the same large sample statistical properties as that obtained via analysis of covariance. However the performance of IPTW has not been explored for smaller population trials (< 100 participants), where precise estimation of the treatment effect has potential for greater impact than in larger samples. Methods In this paper we explore the performance of the baseline adjusted treatment effect estimated using IPTW in smaller population trial settings. To do so we present a simulation study including a number of different trial scenarios with sample sizes ranging from 40 to 200 and adjustment for up to 6 covariates. We also re-analyse a paediatric eczema trial that includes 60 children. Results In the simulation study the performance of the IPTW variance estimator was sub-optimal with smaller sample sizes. The coverage of 95% CI’s was marginally below 95% for sample sizes < 150 and ≥ 100. For sample sizes < 100 the coverage of 95% CI’s was always significantly below 95% for all covariate settings. The minimum coverage obtained with IPTW was 89% with n = 40. In comparison, regression adjustment always resulted in 95% coverage. The analysis of the eczema trial confirmed discrepancies between the IPTW and regression estimators in a real life small population setting. Conclusions The IPTW variance estimator does not perform so well with small samples. Thus we caution against the use of IPTW ...
Keywords	Randomised controlled trial ; Covariate adjustment ; Small population ; Small sample size ; Propensity score ; Inverse probability weighting ; Medicine (General) ; R5-920
Subject code	310
Language	English
Publishing date	2020-03-01T00:00:00Z
Publisher	BMC
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: A framework for handling missing accelerometer outcome data in trials

Mia S. Tackney / Derek G. Cook / Daniel Stahl / Khalida Ismail / Elizabeth Williamson / James Carpenter

Trials, Vol 22, Iss 1, Pp 1-

2021 Volume 18

Abstract: Abstract Accelerometers and other wearable devices are increasingly being used in clinical trials to provide an objective measure of the impact of an intervention on physical activity. Missing data are ubiquitous in this setting, typically for one of two ...

Abstract	Abstract Accelerometers and other wearable devices are increasingly being used in clinical trials to provide an objective measure of the impact of an intervention on physical activity. Missing data are ubiquitous in this setting, typically for one of two reasons: patients may not wear the device as per protocol, and/or the device may fail to collect data (e.g. flat battery, water damage). However, it is not always possible to distinguish whether the participant stopped wearing the device, or if the participant is wearing the device but staying still. Further, a lack of consensus in the literature on how to aggregate the data before analysis (hourly, daily, weekly) leads to a lack of consensus in how to define a “missing” outcome. Different trials have adopted different definitions (ranging from having insufficient step counts in a day, through to missing a certain number of days in a week). We propose an analysis framework that uses wear time to define missingness on the epoch and day level, and propose a multiple imputation approach, at the day level, which treats partially observed daily step counts as right censored. This flexible approach allows the inclusion of auxiliary variables, and is consistent with almost all the primary analysis models described in the literature, and readily allows sensitivity analysis (to the missing at random assumption) to be performed. Having presented our framework, we illustrate its application to the analysis of the 2019 MOVE-IT trial of motivational interviewing to increase exercise.
Keywords	Clinical trial ; Accelerometer ; Wearables ; Missing data ; Multiple imputation ; Medicine (General) ; R5-920
Subject code	310
Language	English
Publishing date	2021-06-01T00:00:00Z
Publisher	BMC
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: The importance of investing in data, models, experiments, team science, and public trust to help policymakers prepare for the next pandemic.

Richard Grieve / Youqi Yang / Sam Abbott / Giridhara R Babu / Malay Bhattacharyya / Natalie Dean / Stephen Evans / Nicholas Jewell / Sinéad M Langan / Woojoo Lee / Geert Molenberghs / Liam Smeeth / Elizabeth Williamson / Bhramar Mukherjee

PLOS Global Public Health, Vol 3, Iss 11, p e

2023 Volume 0002601

Abstract: The COVID-19 pandemic has brought about valuable insights regarding models, data, and experiments. In this narrative review, we summarised the existing literature on these three themes, exploring the challenges of providing forecasts, the requirement for ...

Abstract	The COVID-19 pandemic has brought about valuable insights regarding models, data, and experiments. In this narrative review, we summarised the existing literature on these three themes, exploring the challenges of providing forecasts, the requirement for real-time linkage of health-related datasets, and the role of 'experimentation' in evaluating interventions. This literature review encourages us to broaden our perspective for the future, acknowledging the significance of investing in models, data, and experimentation, but also to invest in areas that are conceptually more abstract: the value of 'team science', the need for public trust in science, and in establishing processes for using science in policy. Policy-makers rely on model forecasts early in a pandemic when there is little data, and it is vital to communicate the assumptions, limitations, and uncertainties (theme 1). Linked routine data can provide critical information, for example, in establishing risk factors for adverse outcomes but are often not available quickly enough to make a real-time impact. The interoperability of data resources internationally is required to facilitate sharing across jurisdictions (theme 2). Randomised controlled trials (RCTs) provided timely evidence on the efficacy and safety of vaccinations and pharmaceuticals but were largely conducted in higher income countries, restricting generalisability to low- and middle-income countries (LMIC). Trials for non-pharmaceutical interventions (NPIs) were almost non-existent which was a missed opportunity (theme 3). Building on these themes from the narrative review, we underscore the importance of three other areas that need investment for effective evidence-driven policy-making. The COVID-19 response relied on strong multidisciplinary research infrastructures, but funders and academic institutions need to do more to incentivise team science (4). To enhance public trust in the use of scientific evidence for policy, researchers and policy-makers must work together to clearly ...
Keywords	Public aspects of medicine ; RA1-1270
Subject code	306
Language	English
Publishing date	2023-01-01T00:00:00Z
Publisher	Public Library of Science (PLoS)
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Relationship between the Bolsa Família national cash transfer programme and suicide incidence in Brazil

Daiane Borges Machado / Elizabeth Williamson / Julia M Pescarini / Flavia J O Alves / Luís F S Castro-de-Araujo / Maria Yury Ichihara / Laura C Rodrigues / Ricardo Araya / Vikram Patel / Maurício L Barreto

PLoS Medicine, Vol 19, Iss 5, p e

A quasi-experimental study.

2022 Volume 1004000

Abstract: Background Socioeconomic factors have been consistently associated with suicide, and economic recessions are linked to rising suicide rates. However, evidence on the impact of socioeconomic interventions to reduce suicide rates is limited. This study ... ...

Abstract	Background Socioeconomic factors have been consistently associated with suicide, and economic recessions are linked to rising suicide rates. However, evidence on the impact of socioeconomic interventions to reduce suicide rates is limited. This study investigates the association of the world's largest conditional cash transfer programme with suicide rates in a cohort of half of the Brazilian population. Methods and findings We used data from the 100 Million Brazilian Cohort, covering a 12-year period (2004 to 2015). It comprises socioeconomic and demographic information on 114,008,317 individuals, linked to the "Bolsa Família" programme (BFP) payroll database, and nationwide death registration data. BFP was implemented by the Brazilian government in 2004. We estimated the association of BFP using inverse probability of treatment weighting, estimating the weights for BFP beneficiaries (weight = 1) and nonbeneficiaries by the inverse probability of receiving treatment (weight = E(ps)/(1-E(ps))). We used an average treatment effect on the treated (ATT) estimator and fitted Poisson models to estimate the incidence rate ratios (IRRs) for suicide associated with BFP experience. At the cohort baseline, BFP beneficiaries were younger (median age 27.4 versus 35.4), had higher unemployment rates (56% versus 32%), a lower level of education, resided in rural areas, and experienced worse household conditions. There were 36,742 suicide cases among the 76,532,158 individuals aged 10 years, or older, followed for 489,500,000 person-years at risk. Suicide rates among beneficiaries and nonbeneficiaries were 5.4 (95% CI = 5.32, 5.47, p < 0.001) and 10.7 (95% CI = 10.51, 10.87, p < 0.001) per 100,000 individuals, respectively. BFP beneficiaries had a lower suicide rate than nonbeneficiaries (IRR = 0.44, 95% CI = 0.42, 0.45, p < 0.001). This association was stronger among women (IRR = 0.36, 95% CI = 0.33, 0.38, p < 0.001), and individuals aged between 25 and 59 (IRR = 0.41, 95% CI = 0.40, 0.43, p < 0.001). Study ...
Keywords	Medicine ; R
Subject code	360
Language	English
Publishing date	2022-05-01T00:00:00Z
Publisher	Public Library of Science (PLoS)
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Observational retrospective study calculating health service costs of patients receiving surgery for chronic rhinosinusitis in England, using linked patient-level primary and secondary care electronic data

Stephen Morris / Mike Thomas / Claire Hopkins / Helen Blackshaw / Carl M Philpott / Elizabeth Williamson / James R Carpenter / Spiros Denaxas / Anne G M Schilder / Caroline S Clarke

BMJ Open, Vol 12, Iss

2022 Volume 2

Keywords	Medicine ; R
Language	English
Publishing date	2022-02-01T00:00:00Z
Publisher	BMJ Publishing Group
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Peer advocacy and access to healthcare for people who are homeless in London, UK

Alec Miners / Dee Menezes / Serena Luchenski / Alistair Story / Lucy Platt / Elizabeth Williamson / Sujit D Rathod / Andrew Guise / PJ Annand / Paniz Hosseini / Kate Bowgett / Martin Burrows

BMJ Open, Vol 11, Iss

a mixed method impact, economic and process evaluation protocol

2021 Volume 6

Abstract: Introduction People who are homeless experience higher morbidity and mortality than the general population. These outcomes are exacerbated by inequitable access to healthcare. Emerging evidence suggests a role for peer advocates—that is, trained ... ...

Abstract	Introduction People who are homeless experience higher morbidity and mortality than the general population. These outcomes are exacerbated by inequitable access to healthcare. Emerging evidence suggests a role for peer advocates—that is, trained volunteers with lived experience—to support people who are homeless to access healthcare.Methods and analysis We plan to conduct a mixed methods evaluation to assess the effects (qualitative, cohort and economic studies); processes and contexts (qualitative study); fidelity; and acceptability and reach (process study) of Peer Advocacy on people who are homeless and on peers themselves in London, UK. People with lived experience of homelessness are partners in the design, execution, analysis and dissemination of the evaluation.Ethics and dissemination Ethics approval for all study designs has been granted by the National Health Service London—Dulwich Research Ethics Committee (UK) and the London School of Hygiene and Tropical Medicine’s Ethics Committee (UK). We plan to disseminate study progress and outputs via a website, conference presentations, community meetings and peer-reviewed journal articles.
Keywords	Medicine ; R
Subject code	306
Language	English
Publishing date	2021-06-01T00:00:00Z
Publisher	BMJ Publishing Group
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: The BRAIN-Q, a tool for assessing self-reported sport-related concussions for epidemiological studies

Laura James / Madeline Davies / Saba Mian / Giulia Seghezzo / Elizabeth Williamson / Simon Kemp / Nigel Arden / Damien McElvenny / Neil Pearce / Valentina Gallo

Epidemiology and Health, Vol

2021 Volume 43

Abstract: OBJECTIVES The BRAIN-Q is a tool aimed at maximising the accuracy and minimising measurement error for retrospectively assessing concussions. This paper reports the agreement of the BRAIN-Q tool when compared to extant questionnaire questions, and its ... ...

Abstract	OBJECTIVES The BRAIN-Q is a tool aimed at maximising the accuracy and minimising measurement error for retrospectively assessing concussions. This paper reports the agreement of the BRAIN-Q tool when compared to extant questionnaire questions, and its reproducibility when compared with its telephonic version (tBRAIN-Q). METHODS The BRAIN-Q entails a 3-stage process: defining a concussion, creating a visual timeline with life events, and establishing detailed characteristics for each reported concussion. It was designed to be administered in-person by trained personnel, and was used in the BRAIN study. Its performance was compared with the MSK study, which previously collected a few questions in a broader self-administered questionnaire, and with the tBRAIN-Q Recall, its telephonic version. RESULTS In total, 101 participants were included, of whom 9 were re-assessed with the tBRAIN-Q. The agreement of the BRAIN-Q with the muscle skeletal-questionnaire for rugby-related concussion was 86.7% (κ=0.6). Rugby-related concussion with loss of consciousness showed lower agreement (82.0%; κ=0.6). The comparison between the BRAIN-Q and the tBRAIN-Q showed good reproducibility. CONCLUSIONS The BRAIN-Q is a relatively easy tool to administer in face-to-face assessments, and it showed optimal reproducibility. It includes a well-established definition of concussion, and is used to collect detailed information on each concussion, allowing for a number of subgroup analyses (e.g., by severity, age, or context). The BRAIN-Q is easily adaptable to other sporting settings.
Keywords	questionnaire ; evaluation ; brain concussion ; sports medicine ; epidemiologic studies ; Medicine ; R
Subject code	616
Language	English
Publishing date	2021-10-01T00:00:00Z
Publisher	Korean Society of Epidemiology
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Access to routinely collected health data for clinical trials – review of successful data requests to UK registries

Sarah Lensen / Archie Macnair / Sharon B. Love / Victoria Yorke-Edwards / Nurulamin M. Noor / Meredith Martyn / Alexandra Blenkinsop / Carlos Diaz-Montana / Graham Powell / Elizabeth Williamson / James Carpenter / Matthew R. Sydes

Trials, Vol 21, Iss 1, Pp 1-

2020 Volume 11

Abstract: Abstract Background Clinical trials generally each collect their own data despite routinely collected health data (RCHD) increasing in quality and breadth. Our aim is to quantify UK-based randomised controlled trials (RCTs) accessing RCHD for participant ...

Abstract	Abstract Background Clinical trials generally each collect their own data despite routinely collected health data (RCHD) increasing in quality and breadth. Our aim is to quantify UK-based randomised controlled trials (RCTs) accessing RCHD for participant data, characterise how these data are used and thereby recommend how more trials could use RCHD. Methods We conducted a systematic review of RCTs accessing RCHD from at least one registry in the UK between 2013 and 2018 for the purposes of informing or supplementing participant data. A list of all registries holding RCHD in the UK was compiled. In cases where registries published release registers, these were searched for RCTs accessing RCHD. Where no release register was available, registries were contacted to request a list of RCTs. For each identified RCT, information was collected from all publicly available sources (release registers, websites, protocol etc.). The search and data extraction were undertaken between January and May 2019. Results We identified 160 RCTs accessing RCHD between 2013 and 2018 from a total of 22 registries; this corresponds to only a very small proportion of all UK RCTs (about 3%). RCTs accessing RCHD were generally large (median sample size 1590), commonly evaluating treatments for cancer or cardiovascular disease. Most of the included RCTs accessed RCHD from NHS Digital (68%), and the most frequently accessed datasets were mortality (76%) and hospital visits (55%). RCHD was used to inform the primary trial (82%) and long-term follow-up (57%). There was substantial variation in how RCTs used RCHD to inform participant outcome measures. A limitation was the lack of information and transparency from registries and RCTs with respect to which datasets have been accessed and for what purposes. Conclusions In the last five years, only a small minority of UK-based RCTs have accessed RCHD to inform participant data. We ask for improved accessibility, confirmed data quality and joined-up thinking between the registries and the regulatory ...
Keywords	Systematic review ; Routinely collected health data ; Registry ; RCT ; Medicine (General) ; R5-920
Subject code	310
Language	English
Publishing date	2020-05-01T00:00:00Z
Publisher	BMC
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Specificity of end resection pathways for double-strand break regions containing ribonucleotides and base lesions

James M. Daley / Nozomi Tomimatsu / Grace Hooks / Weibin Wang / Adam S. Miller / Xiaoyu Xue / Kevin A. Nguyen / Hardeep Kaur / Elizabeth Williamson / Bipasha Mukherjee / Robert Hromas / Sandeep Burma / Patrick Sung

Nature Communications, Vol 11, Iss 1, Pp 1-

2020 Volume 12

Abstract: DNA double-strand break repair by homologous recombination initiates with nucleolytic resection of the 5’ DNA strand at the break ends. Here, the authors reveal that the lesion context influences the action and efficiency of the long range resection ... ...

Abstract	DNA double-strand break repair by homologous recombination initiates with nucleolytic resection of the 5’ DNA strand at the break ends. Here, the authors reveal that the lesion context influences the action and efficiency of the long range resection factors EXO1 and BLM-DNA2.
Keywords	Science ; Q
Language	English
Publishing date	2020-06-01T00:00:00Z
Publisher	Nature Portfolio
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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