Matching Methods for Time-Varying Observational Studies R package rsmatch version 0.2.1 Implements popular methods for matching in time-varying observational studies. Matching is difficult in this scenario because participants can be treated at different times which may have an influence on the outcomes. The core methods include: "Balanced Risk Set Matching" from Li, Propert, and Rosenbaum (2011) <doi:10.1198/016214501753208573> and "Propensity Score Matching with Time-Dependent Covariates" from Lu (2005) <doi:10.1111/j.1541-0420.2005.00356.x>. Some functions use the 'Gurobi' optimization back-end to improve the optimization problem speed; the 'gurobi' R package and associated software can be downloaded from <https://www.gurobi.com> after obtaining a license. Software Depends: R (>= 2.10) Imports: dplyr, MASS, Matrix, stats Suggests: gurobi, knitr, nbpMatching, Rglpk, rlang, rmarkdown, survival, testthat Sean Kent <skent259@gmail.com> Comprehensive R Archive Network (CRAN) Sean Kent [aut, cre, cph] (ORCID: <https://orcid.org/0000-0001-8697-9069>), Mitchell Paukner [aut, cph] (ORCID: <https://orcid.org/0000-0003-3839-5311>) MIT + file LICENSE (https://CRAN.R-project.org/package=rsmatch/LICENSE) 2024-02-20 application/tgz https://CRAN.R-project.org/package=rsmatch doi:10.32614/CRAN.package.rsmatch