求“homogeneous treatment assumption”的含义和英文解释。越详细越好，谢谢大家了。最好有中文和英文一起。
补充：是在Panel Data的应用中的含义。

原句是：“If treatment effects are heterogeneous but the homogeneous treatment assumption is imposed in the empirical analysis,
state and concisely explain the consequences for the estimation results.”