Combined with foreign and domestic research data, we found: Subjects age span is imbalance, there are more research on the elderly and less on young people and children relatively.

综合国内外的研究资料发现：研究对象年龄跨度不平衡，针对老年人的研究比较多，对青少年和儿童的研究比较少。

youdao

Combined with foreign and domestic research data, we found: Subjects age span is imbalance, there are more research on the elderly and less on young people and children relatively.

综合国内外的研究资料发现：研究对象年龄跨度不平衡，针对老年人的研究比较多，对青少年和儿童的研究比较少。

youdao