Results 261 to 270 of about 4,409,426 (307)
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Annals of Internal Medicine, 1983
Excerpt To the editor: The nomograms described by Young and associates (1) enable rapid estimation of sample size appropriate for study of an hypothesis.
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Excerpt To the editor: The nomograms described by Young and associates (1) enable rapid estimation of sample size appropriate for study of an hypothesis.
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On the Determination of Sample Size
Epidemiology, 2003Epidemiologists face issues of sample size every time they design a study. Sample size determi? nation has two distinct aspects. One is the tech? nical aspect of how to calculate the sample size re? quired to meet the desired Type I error rate and the power for any specified state of nature. (By "state of nature," I mean the exact point in the relevant
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American Journal of Infection Control, 2012
A quick review of the basics of sample size and power is presented. Readers can participate in an online exercise that introduces them to a power calculator that can be used in their practice, and illustrates the concepts discussed in the article.
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A quick review of the basics of sample size and power is presented. Readers can participate in an online exercise that introduces them to a power calculator that can be used in their practice, and illustrates the concepts discussed in the article.
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2007
In this chapter, we discuss the concept of statistical power and show how the sample size can be chosen to ensure a desired power. Power is the probability of rejecting the null hypothesis when the null hypothesis is false, that is the probability of saying there is a difference when a difference actually exists.
L Douglas, Case, Walter T, Ambrosius
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In this chapter, we discuss the concept of statistical power and show how the sample size can be chosen to ensure a desired power. Power is the probability of rejecting the null hypothesis when the null hypothesis is false, that is the probability of saying there is a difference when a difference actually exists.
L Douglas, Case, Walter T, Ambrosius
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The American Statistician, 2003
Conventionally, sample size calculations are viewed as calculations determining the right number of subjects needed for a study. Such calculations follow the classical paradigm: for a difference X, I need sample size Y. We argue that the paradigm for a sample size Y, I get information Z is more appropriate for many studies and reflects the information ...
Parker R.A., Berman N.G.
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Conventionally, sample size calculations are viewed as calculations determining the right number of subjects needed for a study. Such calculations follow the classical paradigm: for a difference X, I need sample size Y. We argue that the paradigm for a sample size Y, I get information Z is more appropriate for many studies and reflects the information ...
Parker R.A., Berman N.G.
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The Lancet, 1993
A preliminary analysis of data obtained during Britain's first large national survey of sexual attitudes and lifestyles has lately been published.1 This survey was designed to estimate the size of the HIV epidemic and to collect data that could be used to formulate effective preventive strategies.
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A preliminary analysis of data obtained during Britain's first large national survey of sexual attitudes and lifestyles has lately been published.1 This survey was designed to estimate the size of the HIV epidemic and to collect data that could be used to formulate effective preventive strategies.
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BMJ, 2010
A randomised controlled trial investigated whether a computerised feedback device modified eating behaviour and resulted in weight loss in obese adolescents.1 The primary outcome was change in body mass index (BMI) from recruitment to 12 months. BMI was calculated as weight (kg)/[height (m)]2, adjusted for age and sex.
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A randomised controlled trial investigated whether a computerised feedback device modified eating behaviour and resulted in weight loss in obese adolescents.1 The primary outcome was change in body mass index (BMI) from recruitment to 12 months. BMI was calculated as weight (kg)/[height (m)]2, adjusted for age and sex.
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Revista Española de Cardiología (English Edition), 2020
José, Abellán-Huerta +1 more
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José, Abellán-Huerta +1 more
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Journal of the American Veterinary Medical Association, 1990
C R, Curtis, M D, Salman, S, Shott
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C R, Curtis, M D, Salman, S, Shott
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