Criteria for assessment of prognostic factors

In oncology prognostic factors are defined as variables (covariates) with i ndependent influence on outcome. Toxicity and complications of treatment ar e not considered. The significance and independence of a putative prognosti c factor has to be proven by multivariate analysis, The results of prognost ic factor analysis differ depending on tumor entity and residual tumor stat us, Sometimes differences are observed for various endpoints and certain pa tient subgroups. For identification of prognostic factors a systematic step -wise procedure is recommended. A checklist of important methodological asp ects is suggested. The acceptance. of new prognostic factors requires a sta ndardized way to determine the factors, adequate evidence of significance a nd independence and the demonstration of additional prognostic information and its clinical relevance. By integration of multiple prognostic factors t he present turner classification will be extended to prognostic systems.