DESIGN: a randomized control observation.

设计：随机对照观察。

youdao

DESIGN: Retrospective analysis and self pre-and post-control observation.

设计：回顾性分析及自身前后对照观察。

youdao

DESIGN: Retrospective analysis and self pre-and post-control observation.

设计：回顾性分析及自身前后对照观察。

youdao