Flexible Instrumental Variable Methods for Survival Analysis // Instrumental variable analysis methods for causal inference on survival data based on the Cox model allowing for various treatment and effect types, including orthogonality method-of- moments instrumental variable estimation for the Cox model, two-stage residual inclusion Cox estimation with frailty, sequential trial emulation, sequential Cox analyses, and sequential two-stage residual inclusion Cox analyses. Methodological background includes MacKenzie et al. (2014) doi:10.1007/s10742-014-0117-x, Martinez-Camblor et al. (2019) doi:10.1093/biostatistics/kxx062, Martinez-Camblor et al. (2019) doi:10.1111/rssc.12341, Gran et al. (2010) doi:10.1002/sim.4048, and Keogh et al. (2023) doi:10.1002/sim.9718.