Avoid language bias Perhaps one important application is to avoid language bias in our literature reviews [65] . Back in 1995, Grégoire et al. [66] found that among the 36 consecutive metaanalyses that they analysed, one would produce a different conclusion had it not excluded studies based on linguistic reasons. Comparing English and German journals, Egger et al. [67] found that randomised controlled trials (RCTs) were more likely to publish in English language journals if they gave statistically significant results. This led to the worry that language bias could be introduced to reviews and meta-analyses restricted to data published in English, leading to distorted results. However, subsequent studies [68] [69] [70] found little evidence supporting this assertion. Pham et al. found that language bias led to an under-estimation of the protective effect of intervention in RCTs in complementary and alternative medicine (CAM) systematic reviews but not in that of conventional medicine [70] .