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Rigorous scientific review of research protocols is critical to making funding decisions, and to the protection of both human and non-human research participants. Given the increasing complexity of research designs and data analysis methods, quantitative experts, such as biostatisticians, play an essential role in evaluating the rigor and reproducibility of proposed methods. However, there is a common misconception that a statistician’s input is relevant only to sample size/power and statistical analysis sections of a protocol. The comprehensive nature of a biostatistical review coupled with limited guidance on key components of protocol review motived this work. Members of the Biostatistics, Epidemiology, and Research Design Special Interest Group of the Association for Clinical and Translational Science used a consensus approach to identify the elements of research protocols that a biostatistician should consider in a review, and provide specific guidance on how each element should be reviewed. We present the resulting review framework as an educational tool and guideline for biostatisticians navigating review boards and panels. We briefly describe the approach to developing the framework, and we provide a comprehensive checklist and guidance on review of each protocol element. We posit that the biostatistical reviewer, through their breadth of engagement across multiple disciplines and experience with a range of research designs, can and should contribute significantly beyond review of the statistical analysis plan and sample size justification. Through careful scientific review, we hope to prevent excess resource expenditure and risk to humans and animals on poorly planned studies.
Infective endocarditis is a microbial infection of the endothelial surface of the heart, predominantly the heart valves, that is associated with high mortality and morbidity. Few contemporary data exist regarding affected children in our context.
Aims and Objectives:
We aimed to describe the profile and treatment outcomes of infant and childhood endocarditis at our facilities.
This is a retrospective analysis of infants and children with endocarditis at two public sector hospitals in the Western Cape Province of South Africa over a 5-year period. Patients with “definite” and “possible” endocarditis according to Modified Duke Criteria were included in the review.
Forty-nine patients were identified for inclusion; 29 had congenital heart disease as a predisposing condition; 64% of patients met “definite” and 36% “possible” criteria. The in-hospital mortality rate was 20%; 53% of patients underwent surgery with a post-operative mortality rate of 7.7%. The median interval from diagnosis to surgery was 20 days (interquartile range, 9–47 days). Valve replacement occurred in 28% and valve repair in 58%. There was a significant reduction in valvular dysfunction in patients undergoing surgery and only a marginal improvement in patients treated medically. Overall, 43% of patients had some degree of residual valvular dysfunction.
Endocarditis is a serious disease with a high in-hospital mortality and presents challenges in making an accurate diagnosis. Despite a significant reduction in valvular dysfunction, a portion of patients had residual valvular dysfunction. Early surgery is associated with a lower mortality rate, but a higher rate of valve replacement compared with delayed surgery.
Congenital and acquired heart diseases are highly prevalent in developing countries despite limited specialised care. Namibia established a paediatric cardiac service in 2009 with significant human resource and infrastructural constraints. Therefore, patients are referred for cardiac interventions to South Africa.
To describe the diagnoses, clinical characteristics, interventions, post-operative morbidity and mortality, and follow-up of patients referred for care.
Demographics, diagnoses, interventions, intra- and post-operative morbidity and mortality, as well as longitudinal follow-up data of all patients referred to South Africa, were recorded and analysed.
The total cohort constituted 193 patients of which 179 (93%) had CHD and 7% acquired heart disease. The majority of patients (78.8%) travelled more than 400 km to Windhoek before transfer. There were 28 percutaneous interventions. Palliative and definitive surgery was performed in 27 and 129 patients, respectively. Out of 156 patients, 80 (51.3%) had post-operative complications, of which 15 (9.6%) were a direct complication of surgery. Surgical mortality was 8/156 (5.1%, 95% confidence interval 2.2–9.8), with a 30-day mortality of 3.2%. Prolonged ICU stay was associated with a 5% increased risk of death with hazard ratio 1.05, 95% confidence interval 1.02–1.08, p=0.001. Follow-up was complete in 151 (78%) patients for more than 7 years.
Despite the challenges associated with a cardiac programme for referring patients seeking intervention in a neighbouring country and the adverse characteristics of multiple lesions and complexity associated with late presentation, we report good surgical and interventional outcomes. Our goal remains to develop a comprehensive sustainable cardiac service in Namibia.
It is increasingly essential for medical researchers to be literate in statistics, but the requisite degree of literacy is not the same for every statistical competency in translational research. Statistical competency can range from ‘fundamental’ (necessary for all) to ‘specialized’ (necessary for only some). In this study, we determine the degree to which each competency is fundamental or specialized.
We surveyed members of 4 professional organizations, targeting doctorally trained biostatisticians and epidemiologists who taught statistics to medical research learners in the past 5 years. Respondents rated 24 educational competencies on a 5-point Likert scale anchored by ‘fundamental’ and ‘specialized.’
There were 112 responses. Nineteen of 24 competencies were fundamental. The competencies considered most fundamental were assessing sources of bias and variation (95%), recognizing one’s own limits with regard to statistics (93%), identifying the strengths, and limitations of study designs (93%). The least endorsed items were meta-analysis (34%) and stopping rules (18%).
We have identified the statistical competencies needed by all medical researchers. These competencies should be considered when designing statistical curricula for medical researchers and should inform which topics are taught in graduate programs and evidence-based medicine courses where learners need to read and understand the medical research literature.
The purpose of this cross-sectional descriptive study was to describe the particular types of behavioral problems, self-concept, and symptoms of depression experienced by children with both low IQ and epilepsy. Three groups of children (83 males, 81 females; mean age 11 years 10 months, SD 1 year 10 months; age range 9 to 14 years) with epilepsy were compared: (Group 1) Low IQ (<85), n=48, 25 males, 23 females; (Group 2) Middle IQ (85 to 100), n=58, 24 males, 34 females; and (Group 3) High IQ (>100), n=58, 34 males, 24 females. The Child Behavior Checklist, Piers–Harris Self-Concept Scale, and Children's Depression Inventory were used to measure behavior, self-concept, and depression respectively. Results indicated that children in the Low IQ group had the most behavioral and mental health problems. Additionally, there were IQ group-by-sex interactions, with females in the Low IQ group being at the highest risk for poor self-concept. Findings suggest that children with both epilepsy and low IQ should be carefully assessed for mental health problems in the clinical setting.
Central to nanofabrication is the ability to transfer a pattern from an imaging layer to a device or structure. At the smallest dimensions (<20 nm), thin resists or imaging layers have been used exclusively. The transfer of a pattern that is formed in a thin layer resist presents severe technological challenges to resist materials development. A novel approach based on self-assembling monomolecular layer resists is demonstrated with two organosilane films, formed from (aminoethylaminomethyl)phenethyltrimethoxysilane (PEDA) and 4-chloromethylphenyltrichlorosilane (CMPTS). The molecules have separate chemical functionalities for binding to a Si substrate and for promoting chemistry leading to catalysis and the growth of an electroless plated metal film. STM lithographic exposure destroys the ability of the molecule to bind to a catalyst, which initiates an electroless metallization. This forms the basis for a selective imaging and the pattern transfer process. A 25 nm thick Ni layer acts as a very robust etch mask, even as the unmasked regions of Si are etched as deep as 5 μm by reactive ion etching with SF6. With our process 15 nm lines with 3.3 nm edge roughness have been fabricated in the plated Ni and etched into the underlying Si. The development of the resist process and the STM lithography will be described and the resolution of the approach will be discussed.
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