by Usha Govindarajulu | Jul 19, 2023 | Biostatistics, Usha Govindarajulu
Statistical issues in survival analysis (Part XI) July 19, 2023 The authors, Ning et al, have proposed what they refer to as a “broad class” of “so called” Cox-Aalen transformation models which have elements of both multiplicative and additive covariate effects...
by Usha Govindarajulu | Jul 6, 2023 | Biostatistics, Blog, Usha Govindarajulu
July 5, 2023 The restricted mean survival time (RMST) is a concept that has been invented in survival analysis as an alternative to the hazards ratio, which can be difficult to interpret and also, as derived from Cox model, can have difficulty fitting into the...
by Usha Govindarajulu | May 24, 2023 | Biostatistics, Blog, Professor, Usha Govindarajulu
May 24, 2023 The authors developed a semiparametric maximum likelihood estimation procedure via a kernel smoothed-aided expectation-maximization algorithm. The variances for this were estimated through weighted bootstrap. The authors focused on this for the...
by Usha Govindarajulu | Mar 29, 2023 | Biostatistics, Blog, New York
Statistical issues in general (Part I) March 27, 2023 In an article that first appeared in 2021 in Biometrics but is now finally open access in the same journal , the authors, Moss and Bin discuss how publication bias and p-hacking have had strong effects on...
by Usha Govindarajulu | Feb 15, 2023 | Biostatistics, Blog, New York, Usha Govindarajulu
February 15, 2023 In an article recently published in the Biometrical Journal, Magir and Jimenez discuss delayed separation of survival curves with proposals for a new weighted log-rank test to handle this through stratification. This common problem has occurred in...