在观察性研究中,我们常常不得不依赖于无法直接检验的假设。
"In observational studies, we often have to rely on assumptions that are not directly testable."
I’m just a kid trying to live my dreams.
在不幸中所表现出来的勇气,通常总是使卑怯的心灵恼怒,而使高尚的心灵喜悦的。