Modelling the distribution of ischaemic stroke-specific survival time using an EM-based mixture approach with random effects adjustment.
A two-component survival mixture model is proposed to analyse a set of ischaemic stroke-specific mortality data. The survival experience of stroke patients after index stroke may be described by a subpopulation of patients in the acute condition and another subpopulation of patients in the chronic phase. To adjust for the inherent correlation of observations due to random hospital effects, a mixture model of two survival functions with random effects is formulated. Assuming a Weibull hazard in both components, an EM algorithm is developed for the estimation of fixed effect parameters and variance components. A simulation study is conducted to assess the performance of the two-component survival mixture model estimators. Simulation results confirm the applicability of the proposed model in a small sample setting.
Ng
S K
SK
Department of Mathematics, University of Queensland, Brisbane, QLD 4072, Australia. skn@maths.uq.edu.au
McLachlan
G J
GJ
Yau
Kelvin K W
KK
Lee
Andy H
AH
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D003198:Computer Simulation; D005260:Female; D006761:Hospitals / Q000592:standards; D006801:Humans; D008297:Male; D008955:Models, Cardiovascular; D015233:Models, Statistical; D012737:Sex Factors; D020521:Stroke / Q000401:mortality*; D016019:Survival Analysis; D014904:Western Australia / Q000453:epidemiology