Included studies | Publishing time | Document type | Evidence lifting factor | Grade |
Fushan Qin [20] | 2007 | CR | Nothing | Low |
Tao Zhang [21] | 1993 | CR | Added drug interference (−1) | Very low |
Huaisheng Li [22] | 1996 | CR | Added drug interference (−1) | Very low |
Chonglin Mou [23] | 1997 | CR | Added drug interference (−1) | Very low |
Yan Shi [24] | 2001 | CR | Added drug interference (−1) | Very low |
Xiaofen Wei [25] | 2002 | CR | Added drug interference (−1) | Very low |
Weiping Shen [26] | 2003 | CR | Added drug interference (−1) | Very low |
Yufang He [27] | 2005 | 'RCT | Limitation of the study (−2) | Very low |
|
|
| Added drug interference (−1) |
|
Yijuan Zhang [28] | 2006 | CR | Added drug interference (−1) | Very low |
Jianchun Yu [29] | 2008 | CR | Added drug interference (−1) | Very low |