We consider identification of optimal dynamic treatment regimes in a setting where time-varying treatments are confounded by hidden time-varying confounders, but proxy variables of the unmeasured confounders are available. We show that, with two independent proxy variables at each time point that are sufficiently relevant for the hidden confounders, identification of the joint distribution of counterfactuals is possible, thereby facilitating identification of an optimal treatment regime.

翻译：我们考虑在时间变化的治疗受到隐藏时间变化混杂因子干扰，但可获得未测量混杂因子代理变量的情境下，识别最优动态治疗方案。我们证明，在每个时间点存在两个与隐藏混杂因子充分相关的独立代理变量时，反事实联合分布的可识别性得以实现，从而促进最优治疗方案的识别。