title: Relative survival multistate Markov model.
abstract: Prognostic studies often have to deal with two important challenges: (i) separating effects of predictions on different 'competing' events and (ii) uncertainty about cause of death. Multistate Markov models permit multivariable analyses of competing risks of, for example, mortality versus disease recurrence. On the other hand, relative survival methods help estimate disease-specific mortality risks even in the absence of data on causes of death. In this paper, we propose a new Markov relative survival (MRS) model that attempts to combine these two methodologies. Our MRS model extends the existing multistate Markov piecewise constant intensities model to relative survival modeling. The intensity of transitions leading to death in the MRS model is modeled as the sum of an estimable excess hazard of mortality from the disease of interest and an 'offset' defined as the expected hazard of all-cause 'natural' mortality obtained from relevant life-tables. We evaluate the new MRS model through simulations, with a design based on registry-based prognostic studies of colon cancer. Simulation results show almost unbiased estimates of prognostic factor effects for the MRS model. We also applied the new MRS model to reassess the role of prognostic factors for mortality in a study of colorectal cancer. The MRS model considerably reduces the bias observed with the conventional Markov model that does not permit accounting for unknown causes of death, especially if the 'true' effects of a prognostic factor on the two types of mortality differ substantially.
authors: Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada.
authors: Ella
authors: E
authors: Huszti
authors: Michal
authors: M
authors: Abrahamowicz
authors: Ahmadou
authors: A
authors: Alioum
authors: Christine
authors: C
authors: Binquet
authors: Catherine
authors: C
authors: Quantin
mesh_terms: D003110:Colonic Neoplasms / Q000401:mortality; D015179:Colorectal Neoplasms / Q000401:mortality; D003198:Computer Simulation / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D015993:Life Tables; D008297:Male; D008390:Markov Chains; D011379:Prognosis; D012008:Recurrence; D016019:Survival Analysis