Interim Monitoring of Clinical Trials with Time-Lagged Outcome R package tLagInterim version 1.1 CRAN Task View: ClinicalTrials (https://CRAN.R-project.org/view=ClinicalTrials) Implements inverse and augmented inverse probability weighted estimators for common treatment effect parameters at an interim analysis with time-lagged outcome that may not be available for all enrolled subjects. Produces estimators, standard errors, and information that can be used to compute stopping boundaries using software that assumes that the estimators/test statistics have independent increments. Tsiatis, A. A. and Davidian, M., (2022) <doi:10.1002/sim.9580> . Software Depends: R (>= 3.5.0), survival Imports: R.utils Shannon T. Holloway <shannon.t.holloway@gmail.com> Comprehensive R Archive Network (CRAN) Shannon T. Holloway [aut, cre], Marie Davidian [aut], Anastasios Tsiatis [aut] GPL-2 2025-05-04 application/tgz https://CRAN.R-project.org/package=tLagInterim doi:10.32614/CRAN.package.tLagInterim