RECaST-Surv: A Calibrated Borrowing Method for Survival Endpoints in Unequal Randomized Trials
本文提出RECaST-Surv方法,通过借用外部对照数据来解决不均衡随机试验中生存终点分析效率低的问题,并控制I类错误率。
本文提出RECaST-Surv方法,通过借用外部对照数据来解决不均衡随机试验中生存终点分析效率低的问题,并控制I类错误率。
Objective Prediction models are commonly trained using objectives such as Bernoulli negative log-likelihood (NLL), although downstream clinical decisions may depend on specific risk thresholds. We introduce Smooth Net Benefit ($σ$NB), a differentiable approximation of Net Benefit designed to align model training with threshold-specific clinical utility. Materials and Methods We evaluated $σ$NB as a training objective for logistic regression, generalized additive models (GAMs), and XGBoost with three Hessian implementations. Experiments used the Framingham cardiovascular risk dataset and 44 TabZilla datasets comprising 72 dataset-threshold combinations. Results $σ$NB training did not consistently improve Net Benefit in Framingham. Across the TabZilla benchmark, mean standardized Net Benefit for logistic regression increased from 0.5669 with NLL to 0.5765 with $σ$NB (mean difference 0.0096, 95% CI -0.0001 to 0.0193). For GAMs, mean standardized Net Benefit decreased from 0.5921 to 0.5625 (mean difference -0.0296, 95% CI -0.0721 to 0.0129). For XGBoost, NLL achieved 0.6745 compared with 0.6723--0.6735 across $σ$NB implementations. In logistic regression, $σ$NB gains were positively associated with the performance advantage of XGBoost over NLL-trained logistic regression. Discussion The effect of $σ$NB was context dependent, with modest gains concentrated in logistic regression and little benefit for more flexible model classes. This suggests that decision-focused optimization may be most useful when limited model flexibility leaves greater scope for improvement. Conclusion Our results do not support $σ$NB as a general replacement for NLL training, but support further investigation of decision-focused objectives in settings where conventional likelihood-based training may not adequately capture decision-relevant structure.
研究通过分析CENTER-TBI队列中4,509名患者的数据,采用多种聚类算法和参数选择方法,探讨了不同选择对聚类结果的影响,揭示了无监督聚类在定义患者亚组时的不稳定性。
论文探讨了在联合模型中选择合适的功能形式以连接生物标志物轨迹与事件风险的问题,通过对比不同关联结构并应用实例说明其重要性。
This work addresses the challenge of applying concept bottleneck models to cancer imaging diagnosis, where reliance on extensive instance-level concept annotations limits practicality. To mitigate this dependency, the authors propose a prior-guided hybrid concept bottleneck model that integrates sparse concept annotations, class-conditional concept distribution matching on unlabeled data, and prior-informed initialization of the diagnostic head. Evaluated on multi-center cancer imaging datasets, the method demonstrates strong performance even with only 10% concept annotation coverage, achieving concept AUCs of 0.741, 0.787, and 0.642 for breast masses, calcifications, and pulmonary nodules, respectively. The approach attains diagnostic accuracy comparable to black-box models while preserving interpretability through explicit concept reasoning.
本文提出RECaST-Surv方法,通过借用外部对照数据来解决不均衡随机试验中生存终点分析效率低的问题,并控制I类错误率。
Objective Prediction models are commonly trained using objectives such as Bernoulli negative log-likelihood (NLL), although downstream clinical decisions may depend on specific risk thresholds. We introduce Smooth Net Benefit ($σ$NB), a differentiable approximation of Net Benefit designed to align model training with threshold-specific clinical utility. Materials and Methods We evaluated $σ$NB as a training objective for logistic regression, generalized additive models (GAMs), and XGBoost with three Hessian implementations. Experiments used the Framingham cardiovascular risk dataset and 44 TabZilla datasets comprising 72 dataset-threshold combinations. Results $σ$NB training did not consistently improve Net Benefit in Framingham. Across the TabZilla benchmark, mean standardized Net Benefit for logistic regression increased from 0.5669 with NLL to 0.5765 with $σ$NB (mean difference 0.0096, 95% CI -0.0001 to 0.0193). For GAMs, mean standardized Net Benefit decreased from 0.5921 to 0.5625 (mean difference -0.0296, 95% CI -0.0721 to 0.0129). For XGBoost, NLL achieved 0.6745 compared with 0.6723--0.6735 across $σ$NB implementations. In logistic regression, $σ$NB gains were positively associated with the performance advantage of XGBoost over NLL-trained logistic regression. Discussion The effect of $σ$NB was context dependent, with modest gains concentrated in logistic regression and little benefit for more flexible model classes. This suggests that decision-focused optimization may be most useful when limited model flexibility leaves greater scope for improvement. Conclusion Our results do not support $σ$NB as a general replacement for NLL training, but support further investigation of decision-focused objectives in settings where conventional likelihood-based training may not adequately capture decision-relevant structure.
研究通过分析CENTER-TBI队列中4,509名患者的数据,采用多种聚类算法和参数选择方法,探讨了不同选择对聚类结果的影响,揭示了无监督聚类在定义患者亚组时的不稳定性。
论文探讨了在联合模型中选择合适的功能形式以连接生物标志物轨迹与事件风险的问题,通过对比不同关联结构并应用实例说明其重要性。
This work addresses the challenge of applying concept bottleneck models to cancer imaging diagnosis, where reliance on extensive instance-level concept annotations limits practicality. To mitigate this dependency, the authors propose a prior-guided hybrid concept bottleneck model that integrates sparse concept annotations, class-conditional concept distribution matching on unlabeled data, and prior-informed initialization of the diagnostic head. Evaluated on multi-center cancer imaging datasets, the method demonstrates strong performance even with only 10% concept annotation coverage, achieving concept AUCs of 0.741, 0.787, and 0.642 for breast masses, calcifications, and pulmonary nodules, respectively. The approach attains diagnostic accuracy comparable to black-box models while preserving interpretability through explicit concept reasoning.