Issues

• compute_followup_hazard_ratios drops a fitted formula

  CamDavidsonPilon/lifelines#1702 · Filter by author dnncha opened on Sep 27, 2026

• KaplanMeierFitter truncates weighted at-risk counts to integers in the Greenwood variance (wrong/negative variance, degenerate CIs)

  CamDavidsonPilon/lifelines#1701 · Filter by author lucaluo925 opened on Sep 24, 2026

• Use conditional_after times for predict_expectation methods

  CamDavidsonPilon/lifelines#1695 · Filter by author TeyAll opened on Jul 2, 2026

• survival_table_from_events / KaplanMeierFitter accepting negative durations

  CamDavidsonPilon/lifelines#1693 · Filter by author Qayad-Ali opened on Jun 30, 2026

• Pandas 3.0 support

  CamDavidsonPilon/lifelines#1685 · Filter by author huntermills707 opened on Jun 15, 2026

• restricted_mean_survival_time(..., return_variance=True) returns variance of the truncated RV, not the sampling variance — silently produces wrong p-values

  CamDavidsonPilon/lifelines#1682 · Filter by author sebasj13 opened on May 6, 2026

• weightings=“fleming-harrington” cant handle zero values

  CamDavidsonPilon/lifelines#1681 · Filter by author jorflima opened on May 5, 2026

• Use conditional_after times for predict_expectation of WeibullAFTFitter

  CamDavidsonPilon/lifelines#1680 · Filter by author TeyBerendschot opened on Mar 20, 2026
  3

• Episode censoring length creates different hazard estimates in CoxPHFitter

  CamDavidsonPilon/lifelines#1679 · Filter by author gsroma opened on Mar 18, 2026

• Actuarial life-table analysis - any interest in flip-side of survival?

  CamDavidsonPilon/lifelines#1678 · Filter by author dowes48 opened on Mar 16, 2026

• Weights create odd behavior with CoxTimeVaryingFitter()

  CamDavidsonPilon/lifelines#1673 · Filter by author zer2 opened on Mar 3, 2026

• add_at_risk_counts is not working properly with limited max X on plot axis

  CamDavidsonPilon/lifelines#1667 · Filter by author Ventangelo opened on Nov 8, 2025

• Survival prediction from time-varying covariates using PiecwiseExponentialRegressionFitter/CoxTimeVarying

  CamDavidsonPilon/lifelines#1666 · Filter by author knwyne20 opened on Aug 28, 2025

• Restricted cubic spline (RCS) visualization issue in lifelines

  CamDavidsonPilon/lifelines#1664 · Filter by author kcw0331 opened on Aug 26, 2025

• Undesired behaviour for predict_hazard and predict_log_hazard in CoxPHFitter for categoricals

  CamDavidsonPilon/lifelines#1662 · Filter by author AsierRabasco opened on Jul 30, 2025

• Add support for polars

  CamDavidsonPilon/lifelines#1658 · Filter by author pavelzw opened on Jun 13, 2025
  6

• CoxTimeVaryingFitter should warn when subjects don't start at time 0 + unclear documentation

  CamDavidsonPilon/lifelines#1656 · Filter by author vitekzkytek opened on May 28, 2025

• Negative infinity not allowed in KaplanMeierFitter.fit_interval_censoring?

  CamDavidsonPilon/lifelines#1655 · Filter by author noahfranz13 opened on May 2, 2025

• How do I perform the stratified Log-rank test using lifelines package?

  CamDavidsonPilon/lifelines#1654 · Filter by author dominicyu04 opened on Apr 6, 2025

• Discrepancy in Survival Analysis Results Between Python and SAS

  CamDavidsonPilon/lifelines#1652 · Filter by author dominicyu04 opened on Mar 25, 2025
  6

• Additional parameters for "scipy.optimize.minimize" in ParametricRegressionFitter is not functioning correctly

  CamDavidsonPilon/lifelines#1651 · Filter by author Yoonsung1203 opened on Feb 27, 2025

• Formula documentation for predict_partial_hazard function with categorical features

  CamDavidsonPilon/lifelines#1645 · Filter by author tle4336 opened on Nov 22, 2024
  6

• Documentation: Not displaying methods for fitters

  CamDavidsonPilon/lifelines#1644 · Filter by author eroell opened on Nov 20, 2024

• add_at_risk_counts moves grid to the front when using seaborn

  CamDavidsonPilon/lifelines#1642 · Filter by author krz opened on Oct 23, 2024

• AttributeError: 'PiecewiseExponentialRegressionFitter' object has no attribute '_norm_mean'

  CamDavidsonPilon/lifelines#1636 · Filter by author deril2605 opened on Sep 12, 2024