Double-blind evaluation and benchmarking of survival models in a multi-centre study.
Comput Biol Med
; 37(8): 1108-20, 2007 Aug.
Article
in En
| MEDLINE
| ID: mdl-17184760
ABSTRACT
Accurate modelling of time-to-event data is of particular importance for both exploratory and predictive analysis in cancer, and can have a direct impact on clinical care. This study presents a detailed double-blind evaluation of the accuracy in out-of-sample prediction of mortality from two generic non-linear models, using artificial neural networks benchmarked against a partial logistic spline, log-normal and COX regression models. A data set containing 2880 samples was shared over the Internet using a purpose-built secure environment called GEOCONDA (www.geoconda.com). The evaluation was carried out in three parts. The first was a comparison between the predicted survival estimates for each of the four survival groups defined by the TNM staging system, against the empirical estimates derived by the Kaplan-Meier method. The second approach focused on the accurate prediction of survival over time, quantified with the time dependent C index (C(td)). Finally, calibration plots were obtained over the range of follow-up and tested using a generalization of the Hosmer-Lemeshow test. All models showed satisfactory performance, with values of C(td) of about 0.7. None of the models showed a systematic tendency towards over/under estimation of the observed survival at tau=3 and 5 years. At tau=10 years, all models underestimated the observed survival, except for COX regression which returned an overestimate. The study presents a robust and unbiased benchmarking methodology using a bespoke web facility. It was concluded that powerful, recent flexible modelling algorithms show a comparative predictive performance to that of more established methods from the medical and biological literature, for the reference data set.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Computer Simulation
/
Survival Analysis
Type of study:
Clinical_trials
/
Evaluation_studies
/
Prognostic_studies
Limits:
Female
/
Humans
/
Male
/
Middle aged
Country/Region as subject:
Europa
Language:
En
Journal:
Comput Biol Med
Year:
2007
Document type:
Article
Affiliation country: