|Title||Joint Analysis of Survival Time and Longitudinal Categorical Outcomes.|
|Publication Type||Journal Article|
|Year of Publication||2015|
|Authors||Choi, Jaeun, Jianwen Cai, Donglin Zeng, and Andrew F. Olshan|
|Date Published||2015 May|
In biomedical or public health research, it is common for both survival time and longitudinal categorical outcomes to be collected for a subject, along with the subject's characteristics or risk factors. Investigators are often interested in finding important variables for predicting both survival time and longitudinal outcomes which could be correlated within the same subject. Existing approaches for such joint analyses deal with continuous longitudinal outcomes. New statistical methods need to be developed for categorical longitudinal outcomes. We propose to simultaneously model the survival time with a stratified Cox proportional hazards model and the longitudinal categorical outcomes with a generalized linear mixed model. Random effects are introduced to account for the dependence between survival time and longitudinal outcomes due to unobserved factors. The Expectation-Maximization (EM) algorithm is used to derive the point estimates for the model parameters, and the observed information matrix is adopted to estimate their asymptotic variances. Asymptotic properties for our proposed maximum likelihood estimators are established using the theory of empirical processes. The method is demonstrated to perform well in finite samples via simulation studies. We illustrate our approach with data from the Carolina Head and Neck Cancer Study (CHANCE) and compare the results based on our simultaneous analysis and the separately conducted analyses using the generalized linear mixed model and the Cox proportional hazards model. Our proposed method identifies more predictors than by separate analyses.
|Alternate Journal||Stat Biosci|
|Original Publication||Joint analysis of survival time and longitudinal categorical outcomes.|
|PubMed Central ID||PMC4454429|
|Grant List||UL1 TR001111 / TR / NCATS NIH HHS / United States |
R01 CA090731 / CA / NCI NIH HHS / United States
UL1 RR025747 / RR / NCRR NIH HHS / United States
P01 CA142538 / CA / NCI NIH HHS / United States
P2C HD050924 / HD / NICHD NIH HHS / United States
Joint Analysis of Survival Time and Longitudinal Categorical Outcomes.