Systematic Reviews and Meta-Analyses of Traditional Chinese Medicine Must Search Chinese Databases to Reduce Language Bias

Table 1

Comparison of 2 systematic reviews on acupuncture for chronic asthma.

	McCarney et al., 2004 [8]	Yu et al., 2010 [9]
Journal	Cochrane Database of Systematic Reviews	Chinese Acupuncture and Moxibustion
Time period for included studies	Till August 2008	January 2000–October 2009
Chinese databases searched	0	3
International databases searched	3	2
Number of RCTs identified	12	22
Number and % of RCTs identified from Chinese databases	0 (0.00%)	17 (77.27%)
Total number of patients	350	3058
Publication bias	Unable to assess due to a limited number of included studies on each outcome	No clear publication bias for outcomes including total improvement rate, FEV1, and PEFR, unable to assess publication bias on FVC due to a small number of included studies
Main results	No statistically significant or clinically relevant effects were found for acupuncture when compared to sham acupuncture	The acupuncture group showed a greater total improvement rate and significantly improved PEFR, FVC, and FEV1/FVC as compared to its control
Conclusion	No enough evidence for making any conclusions on the value of acupuncture in the treatment of asthma	Acupuncture can significantly improve the overall improvement, PEFR, FVC, and FEV1/FVC

∗PEFR: peak expiratory flow rates; FVC: forced vital capacity; FEV1: forced expiratory volume in one second.