Estimation of median survival and its 95% confidence interval depends on the choice of the survival function, standard error, and a method for constructing the confidence interval. This paper outlines several available possibilities in SAS® (version 9.4) PROC LIFETEST and compares them on theoretical grounds and using simulated data, with criteria: ability to estimate the 95% CI, coverage probability, interval width, and appropriateness for practical use.
View Article and Find Full Text PDFBackground: Coronary heart disease is mainly caused by the effects of obstruction to blood flow in the coronary arteries from discrete mural lesions that encroach into the lumen and usually occur in arteries that are involved by atherosclerosis. Even though the level of certain lipoproteins is indisputably related to the degree of this atherosclerotic involvement of the coronary arteries, the question of whether lipoproteins are also associated with the obstructive lesions remains uncertain.
Methods: This study addressed the question in 53 males (age, 44.
Anaesth Intensive Care
May 1978
A system for humidification with adjustable flows and oxygen concentrations for use in spontaneously breathing patients is described.
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