text_1: 随机 分组 后 , 只有 分配 至 MRI 邀请 组 的 女性 被 告知 分组 情况 , 并 邀请 其 参与 本 试验 .
  
text_2: after randomization , only the women who had been assigned to the MRI @-@ invitation group were informed about the group assignment and were asked to participate in the trial .
  