@article{oai:niigata-u.repo.nii.ac.jp:00015464,
 author = {赤澤, 宏平},
 issue = {5},
 journal = {新潟医学会雑誌, 新潟医学会雑誌},
 month = {May},
 note = {This paper evaluates the loss of power of the simple and stratified logrank tests due to heterogeneity of patients in clinical trials. The results of the paper are based on the analyses of survival data from a large clinical trial which includes more than 6,000 cancer patients. Major findings from the simulation study on power are : (1) for a heterogeneous sample, such as advanced cancer patients, a simple logrank test can yield misleading results and should not be used；（2）the stratified logrank test may suffer some power loss when many prognostic factors need to be considered and the number of patients within stratum is small. To address the problems, due to heterogeneity, the Cox regression method with a piecewise linear hazard model is recommended.},
 pages = {179--185},
 title = {医療統計学を用いた新しい治療効果判定法の開発},
 volume = {114},
 year = {2000}
}