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Atanu Biswas

Bio: Atanu Biswas is an academic researcher from Indian Statistical Institute. The author has contributed to research in topics: Medicine & Covariate. The author has an hindex of 23, co-authored 162 publications receiving 1782 citations.


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Journal ArticleDOI
TL;DR: This study aimed to improve on previous forecasts of dementia prevalence by producing country-level estimates and incorporating information on selected risk factors, using relative risks and forecasted risk factor prevalence to predict GBD risk-attributable prevalence in 2050 globally and by world region and country.

561 citations

Journal ArticleDOI
01 Mar 2007-Stroke
TL;DR: The age standardized prevalence and incidence rates of stroke are similar to or higher than many Western nations, and the overall case fatality rate is among the highest category of stroke fatality in the world.
Abstract: Background and Purpose— Information on essential stroke parameters are lacking in India. This population-based study on stroke disorder was undertaken in the city of Kolkata, India, to determine the subtypes, prevalence, incidence, and case fatality rates of stroke. Methods— This was a longitudinal descriptive study comprising 2-stage door-to-door survey of a stratified randomly selected sample of the city population, conducted twice per year for 2 successive years from March 2003 to February 2005. Results— Out of the screened population of 52 377 (27 626 men, 24 751 women), the age standardized prevalence rate of stroke to world standard population is 545.10 (95% CI, 479.86 to 617.05) per 100 000 persons. The age standardized average annual incidence rate to world standard population of first-ever-in-a-lifetime stroke is 145.30 (95% CI, 120.39 to 174.74) per 100 000 persons per year. Thirty-day case fatality rate is 41.08% (95% CI, 30.66 to 53.80). Women have higher incidence and case fatality rates. Des...

222 citations

Journal ArticleDOI
TL;DR: This paper considers patients who are heterogeneous with respect to some prognostic factors and assumes that the response from each patient is a continuous variable, and considers a normal linear model and provides an allocation design with due attention to the prognostic Factors.
Abstract: SUMMARY Adaptive designs are often used in clinical trials to force balance in sequential allocation of patients between two or more competitive treatments. Sometimes, from ethical considerations, the goal may be to allocate a larger number of patients to the better treatment in the course of the trial. In the present paper we consider patients who are heterogeneous with respect to some prognostic factors and assume that the response from each patient is a continuous variable. We consider a normal linear model and provide an allocation design with due attention to the prognostic factors. The loss of efficiency incurred by using a balanced design is also indicated. Issues of inference based on adaptive allocation are also discussed. Finally a guideline is provided for the appropriate choice of the design parameters.

108 citations

Journal ArticleDOI
TL;DR: In several real-life examples one encounters count data where the number of zeros is such that the usual Poisson distribution does not fit the data, a zero-inflated generalized Poisson model can be considered and a Bayesian analysis can be carried out.

76 citations

Journal ArticleDOI
TL;DR: This work uses optimum design theory to derive a skewed Bayesian biased-coin procedure for sequential designs with continuous responses for adaptive designs, the performance of which is studied numerically and theoretically.
Abstract: Des schemas adaptatifs sont utilises dans des essais cliniques de Phase III pour biaiser l'attribution des traitements en faveur des meilleurs. Nous utilisons la theorie des schemas optimaux pour etablir une procedure bayesienne de tirage au sort biaise pour des schemas sequentiels avec reponses continues. La performance de ces schemas adaptatifs est etudiee a la fois numeriquement et theoriquement. Des proprietes importantes sont la perte et la proportion de sujets alloues au meilleur traitement.

71 citations


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3,152 citations

Journal ArticleDOI
TL;DR: The saimie paper suggests how susceptible individuals could reduce their total intake of aluminium and suggests that although definite proof is still lacking, there is more than enough evidence to fuel further epidemiological investigation.
Abstract: The saimie paper suggests how susceptible individuals could reduce their total intake of aluminium. In presenting the cpidemiological evidence for a link betveen aluminium and Alzheimcr's, Nart'n suggests that although definite proof is still lacking, there is more than enough positixe evidence to fuel further epidemiological investigation. It states that such investigations might specificallx address the issue of the confounding cffect of silicon and an assessment of exposure to spccific

1,353 citations

Journal ArticleDOI
TL;DR: Dementia costs in developing countries are estimated to be US$73 billion yearly, but care demands social protection, which seems scarce in these regions, and use of traditional diets and medicinal plant extracts might aid prevention and treatment.
Abstract: Despite mortality due to communicable diseases, poverty, and human conflicts, dementia incidence is destined to increase in the developing world in tandem with the ageing population Current data from developing countries suggest that age-adjusted dementia prevalence estimates in 65 year olds are high (>or=5%) in certain Asian and Latin American countries, but consistently low (1-3%) in India and sub-Saharan Africa; Alzheimer's disease accounts for 60% whereas vascular dementia accounts for approximately 30% of the prevalence Early-onset familial forms of dementia with single-gene defects occur in Latin America, Asia, and Africa Illiteracy remains a risk factor for dementia The APOE epsilon4 allele does not influence dementia progression in sub-Saharan Africans Vascular factors, such as hypertension and type 2 diabetes, are likely to increase the burden of dementia Use of traditional diets and medicinal plant extracts might aid prevention and treatment Dementia costs in developing countries are estimated to be US$73 billion yearly, but care demands social protection, which seems scarce in these regions

995 citations

Journal ArticleDOI
TL;DR: A framework for understanding how zero-inflated data sets originate and deciding how best to model them is proposed and the different kinds of zeros that occur in ecological data are defined and classified.
Abstract: A common feature of ecological data sets is their tendency to contain many zero values. Statistical inference based on such data are likely to be inefficient or wrong unless careful thought is given to how these zeros arose and how best to model them. In this paper, we propose a framework for understanding how zero-inflated data sets originate and deciding how best to model them. We define and classify the different kinds of zeros that occur in ecological data and describe how they arise: either from 'true zero' or 'false zero' observations. After reviewing recent developments in modelling zero-inflated data sets, we use practical examples to demonstrate how failing to account for the source of zero inflation can reduce our ability to detect relationships in ecological data and at worst lead to incorrect inference. The adoption of methods that explicitly model the sources of zero observations will sharpen insights and improve the robustness of ecological analyses.

870 citations