Estimation of Survivorship in Chronic Disease: The “Actuarial” Method
慢性病生存率的估计：“寿命表”方法
In most follow-up studies in chronic disease assumptions on the parametric form of the survivorship function are not justified. A simple frequency estimate, arising from polygonal approximation, is discussed. It is shown that, for proper limitation of the period over which the survivorship is to be estimated, bias due to nonlinearity may be controlled, without loss in efficiency, by proper choice of the sub-intervals. It is concluded that the method proposed is appropriate…