placebo group的用法和樣例：
例句
- Aderse eents did not differ significantly between the risedronate and placebo groups, the inestigators say.
研究人員說，治療組和安慰劑組的不良反應發生率無顯著差異。 - Although myalgia and pyrexia were more common in treatment groups, dropout rates related to treatment were similar to those in the placebo group.
儘管治療組中，肌痛與發熱更為常見，但由於治療反應而推出的比例，與安慰劑組類似。
