Cancer clinical trials are often subject to misclassification of discrete covariates, measurement errors in continuous covariates, categorization of covariates, model misspecification, and omission of prognositc factors in the analysis. Each of these """"""""errors"""""""" increase the variance of the estimate of the treatment effect thereby increasing the required sample size or increasing the level of significance.
The aims of the proposed study are to quantify the effect these """"""""errors"""""""" have on the precision of the estimate for treatment effect, adjusted for covariates under Cox's proportional hazards model.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Unknown (R23)
Project #
5R23CA039575-02
Application #
3446705
Study Section
(SSS)
Project Start
1985-04-01
Project End
1988-03-31
Budget Start
1986-04-01
Budget End
1987-03-31
Support Year
2
Fiscal Year
1986
Total Cost
Indirect Cost
Name
Wake Forest University Health Sciences
Department
Type
Schools of Medicine
DUNS #
041418799
City
Winston-Salem
State
NC
Country
United States
Zip Code
27106
Morgan, T M (1988) Analysis of duration of response: a problem of oncology trials. Control Clin Trials 9:11-8
Morgan, T M; Elashoff, R M (1987) Effect of covariate measurement error in randomized clinical trials. Stat Med 6:31-41
Morgan, T M (1986) Omitting covariates from the proportional hazards model. Biometrics 42:993-5