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INTRODUCTION: Accurately estimating the costs of clinical trials is challenging. There is currently no reference class data to allow researchers to understand the potential costs associated with database change management in clinical trials. METHODS: We used a case-based approach, summarising post-live changes in eleven clinical trial databases managed by Sheffield Clinical Trials Research Unit. We reviewed the database specifications for each trial and summarised the number of changes, change type, change category, and timing of changes. We pooled our experiences and made observations in relation to key themes. RESULTS: Median total number of changes across the eleven trials was 71 (range 40-155) and median number of changes per study week was 0.48 (range 0.32-1.34). The most common change type was modification (median 39, range 20-90), followed by additions (median 32, range 18-55), then deletions (median 7, range 1-12). In our sample, changes were more common in the first half of the trial's lifespan, regardless of its overall duration. Trials which saw continuous changes seemed more likely to be external pilots or trials in areas where the trial team was either less experienced overall or within the particular therapeutic area. CONCLUSIONS: Researchers should plan trials with the expectation that clinical trial databases will require changes within the life of the trial, particularly in the early stages or with a less experienced trial team. More research is required to understand potential differences between clinical trial units and database types.

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BACKGROUND: The LOVIT (Lessening Organ Dysfunction with Vitamin C) trial is a blinded multicenter randomized clinical trial comparing high-dose intravenous vitamin C to placebo in patients admitted to the intensive care unit with proven or suspected infection as the main diagnosis and receiving a vasopressor. OBJECTIVE: We aim to describe a prespecified statistical analysis plan (SAP) for the LOVIT trial prior to unblinding and locking of the trial database. METHODS: The SAP was designed by the LOVIT principal investigators and statisticians, and approved by the steering committee and coinvestigators. The SAP defines the primary and secondary outcomes, and describes the planned primary, secondary, and subgroup analyses. RESULTS: The SAP includes a draft participant flow diagram, tables, and planned figures. The primary outcome is a composite of mortality and persistent organ dysfunction (receipt of mechanical ventilation, vasopressors, or new renal replacement therapy) at 28 days, where day 1 is the day of randomization. All analyses will use a frequentist statistical framework. The analysis of the primary outcome will estimate the risk ratio and 95% CI in a generalized linear mixed model with binomial distribution and log link, with site as a random effect. We will perform a secondary analysis adjusting for prespecified baseline clinical variables. Subgroup analyses will include age, sex, frailty, severity of illness, Sepsis-3 definition of septic shock, baseline ascorbic acid level, and COVID-19 status. CONCLUSIONS: We have developed an SAP for the LOVIT trial and will adhere to it in the analysis phase. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/36261.

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STUDY DESIGN: Narrative Review. OBJECTIVES: The objective of this study was to compare publication status of clinical trials in adult spine surgery registered on ClinicalTrials.gov by funding source as well as to identify other trends in clinical trials in adult spine surgery. METHODS: All prospective, comparative, therapeutic (intervention-based) trials of adult spinal disease that were registered on ClinicalTrials.gov with a start date of January 1, 2000 and completion date before December 17, 2018 were included. Primary outcome was publication status of published or unpublished. A bivariate analysis was used to compare publication status to funding source of industry vs non-industry. RESULTS: Our search identified 107 clinical trials. The most common source of funding was industry (62 trials, 57.9% of total), followed by University funding (26 trials, 24.3%). The results of 76 trials (71.0%) were published, with industry-funded trials less likely to be published compared to non-industry-funded trials (62.9% compared to 82.2%, P = .03). Of the 31 unpublished studies, 13 did not report any results on ClinicalTrials.gov, and of those with reported results, none was a positive trial. CONCLUSIONS: Clinician researchers in adult spine surgery should be aware that industry-funded trials are less likely to go on to publication compared to non-industry-funded trials, and that negative trials are frequently not published. Future opportunities include improvement in result reporting and in publishing negative studies.

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PURPOSE: To compare retinal vascular parameters between high-risk and low-risk pregnant women over time during pregnancy. METHODS: In a longitudinal study, we included pregnant women with normal blood pressure and normal body mass index (BMI, group 1), pregnant women with systemic hypertension and/or overweight (group 2) and age-matched nonpregnant healthy women (group 3). Using the dynamic vessel analyser (DVA) we investigated flicker-induced vasodilation in retinal arteries (FLA) and veins (FLV), central retinal arterial and vein equivalent (CRAE, CRVE), arterio-venous ratio (AVR) and retinal arterial and venous oxygen saturation (SartO2 , SveinO2 ). Study visits were scheduled 2nd trimester (TP 2), 3rd trimester (TP 3) and postpartum (PP). RESULTS: Data from 29 women in group 1, 25 women in group 2 and 33 women in group 3 were included for analysis. FLA, FLV, CRAE, CRVE, AVR and SveinO2 were altered in group 2 (p-values between < 0.001 and 0.009). At TP 3 the differences between groups were most pronounced. In contrast, there were only minor differences between group 1 and 3. Changes in retinal parameters were independently associated with systemic blood pressure and BMI. CONCLUSIONS: The present analysis indicates that flicker-induced retinal vasodilation, retinal vessel diameters and retinal oxygen saturation are altered in high-risk pregnant women. Hence, these parameters are candidate biomarkers for pregnancy complications, a hypothesis that deserves further study.

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BACKGROUND: The Multiple Sclerosis Outcome Assessments Consortium (MSOAC) was formed by the National MS Society to develop improved measures of multiple sclerosis (MS)-related disability. OBJECTIVES: (1) To assess the current literature and available data on functional performance outcome measures (PerfOs) and (2) to determine suitability of using PerfOs to quantify MS disability in MS clinical trials. METHODS: (1) Identify disability dimensions common in MS; (2) conduct a comprehensive literature review of measures for those dimensions; (3) develop an MS Clinical Data Interchange Standards Consortium (CDISC) data standard; (4) create a database of standardized, pooled clinical trial data; (5) analyze the pooled data to assess psychometric properties of candidate measures; and (6) work with regulatory agencies to use the measures as primary or secondary outcomes in MS clinical trials. CONCLUSION: Considerable data exist supporting measures of the functional domains ambulation, manual dexterity, vision, and cognition. A CDISC standard for MS ( http://www.cdisc.org/therapeutic#MS ) was published, allowing pooling of clinical trial data. MSOAC member organizations contributed clinical data from 16 trials, including 14,370 subjects. Data from placebo-arm subjects are available to qualified researchers. This integrated, standardized dataset is being analyzed to support qualification of disability endpoints by regulatory agencies.

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INTRODUCTION: Rett syndrome (RTT) is a pervasive neurodevelopmental disorder that presents with deficits in brain functioning leading to language and learning regression, characteristic hand stereotypies and developmental delay. Different mutations in the gene implicated in RTT-methyl-CpG-binding protein 2 (MECP2) establishes RTT as a disorder with divergent symptomatology ranging from individuals with severe to milder phenotypes. A reliable and single multidimensional questionnaire is needed that can embrace all symptoms, and the relationships between them, and can map clinically meaningful data to symptomatology across the lifespan in patients with RTT. As part of the HealthTracker-based Tailored Rett Intervention and Assessment Longitudinal (TRIAL) database, the Rett Evaluation of Symptoms and Treatments (REST) Questionnaire will be able to marry with the physiological aspects of the disease obtained using wearable sensor technology, along with genetic and psychosocial data to stratify patients. Taken together, the web-based TRIAL database will empower clinicians and researchers with the confidence to delineate between different aspects of disorder symptomatology to streamline care pathways for individuals or for those patients entering clinical trials. This protocol describes the anticipated development of the REST questionnaire and the TRIAL database which links with the outcomes of the wearable sensor technology, and will serve as a barometer for longitudinal patient monitoring in patients with RTT. METHODS AND ANALYSIS: The US Food and Drug Administration Guidance for Patient-Reported Outcome Measures will be used as a template to inform the methodology of the study. It will follow an iterative framework that will include item/concept identification, item/concept elicitation in parent/carer-mediated focus groups, expert clinician feedback, web-based presentation of questionnaires, initial scale development, instrument refinement and instrument validation. ETHICS AND DISSEMINATION: The study has received favourable opinion from the National Health Service (NHS) Research Ethics Committee (REC): NHS Research Ethics Committee (REC)-London, Bromley Research Ethics Committee (reference: 15/LO/1772).

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