TY  - JOUR
TI  - Comparison of the Statistical Tests for Two Crossing Survival Functions
AB  - ABSTRACT Objective: Testing the equality of two survival functions is frequently used in survival analysis studies. The most preferred method in the literature is the log-rank (LR) test, but it provides misleading results in evaluating the crossing survival functions in which the proportional hazards assumption is violated. Therefore, different comparison tests have been proposed. In this study, currently proposed partitioned LR tests and weighted Lin- Wang tests were compared with LR and weighted LR tests. Material and Methods: Type I error rates and powers of comparison tests were compared in different sample sizes and censoring rates using the Monte Carlo simulation technique. The weaknesses and strengths of the comparison tests were examined in various scenarios. In addition to the simulation study, comparison tests were evaluated using open source real-life data set. Results: Simulation results showed that all tests provided reasonable Type I error rates. The most successful results in the scenarios of crossing survival functions belonged to partitioned LR tests. It was observed that the location of the crossing point affected the performance of the tests adversely. Conclusion: Proportional hazards assumption should be tested before comparing two survival functions. It is recommended to use the LR test, when the proportional hazards assumption is provided and the use of partitioned LR tests in the comparison of crossing survival functions.
AU  - BAL, Cengiz
AU  - ÇOLAK, Ertuğrul
AU  - ÖZEN, Hülya
DO  - 10.5336/biostatic.2020-80208
PY  - 2021
JO  - Türkiye Klinikleri Biyoistatistik Dergisi
VL  - 13
IS  - 1
SN  - 1308-7894
SP  - 13
EP  - 27
DB  - TRDizin
UR  - http://search/yayin/detay/491676
ER  -