Steve Simpson

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BACKGROUND There is a striking latitudinal gradient in multiple sclerosis (MS) prevalence, but exceptions in Mediterranean Europe and northern Scandinavia, and some systematic reviews, have suggested that the gradient may be an artefact. The authors sought to evaluate the association between MS prevalence and latitude by meta-regression. METHODS AND(More)
OBJECTIVE A protective association between higher vitamin D levels and the onset of multiple sclerosis (MS) has been demonstrated; however, its role in modulating MS clinical course has been little studied. We investigated whether higher levels of serum 25-hydroxyvitamin D (25-OH-D) were associated with a lower risk of relapses in people with MS. METHODS(More)
OBJECTIVE To investigate the accuracy of human listeners in identifying epileptic seizures and seizure lateralisation from audified EEG signals. METHODS EEG data from 17 temporal lobe epilepsy patients (9 male, 8 female; aged 23-55) was converted to audio format by 60× time compression. Using a subset of 19% of the data, five auditory participants (2(More)
BACKGROUND A female/male (F/M) ratio increase over time in multiple sclerosis (MS) patients was demonstrated in many countries around the world. So far, a direct comparison of sex ratio time-trends among MS populations from different geographical areas was not carried out. OBJECTIVE In this paper we assessed and compared sex ratio trends, over a 60-year(More)
We begin by presenting a new kind of finite counting theorem which asserts that any function on vectors of natural numbers has few low values over finite sets of arbitrary size (Theorems 0.1 and 0.2 from the introduction). This estimate on the low values (herein called regressive values) is linear in the sizes of the finite sets. This basic counting theorem(More)
BACKGROUND AND PURPOSE White matter structural alterations and the correlation with neuropsychological deficits in children with hydrocephalus have not been well investigated. In this prospective study, the objectives were the following: 1) to apply DTI to detect in vivo white matter alterations based on diffusion properties in children with acute(More)
BACKGROUND AND PURPOSE Hydrocephalus is a severe pathologic condition in which WM damage is a major factor associated with poor outcomes. The goal of the study was to investigate tract-based WM connectivity and DTI measurements in children with hydrocephalus by using the probabilistic diffusion tractography method. MATERIALS AND METHODS Twelve children(More)
To evaluate temporal changes in the geographic distribution of Parkinson's disease (PD) mortality in the United States, we reviewed death rates for PD in the nine regions of the United States for 1980-1984. Age-adjusted mortality for all ages and for the elderly (65 years of age and older) was analyzed. Variation in PD mortality was observed among the(More)
Objectives To assess the overall effect of vitamin D supplementation on risk of acute respiratory tract infection, and to identify factors modifying this effect.Design Systematic review and meta-analysis of individual participant data (IPD) from randomised controlled trials.Data sources Medline, Embase, the Cochrane Central Register of Controlled Trials,(More)
It is now well established that both genetic and environmental factors contribute to and interact in the development of multiple sclerosis (MS). However, the currently described causal genetic variants do not explain the majority of the heritability of MS, resulting in 'missing heritability'. Epigenetic mechanisms, which principally include DNA methylation,(More)