Assessing advances in regional anesthesia by their portrayals in meta-analyses: an alternative view on recent progress

Table 4 Statistics and risk of bias for selected outcomes

Outcome#	Authors	Trials	Participants with outcome	Statistical Analysis			Risk of bias^c
Outcome#	Authors	Trials	Participants with outcome	P-value	Effect size^a	Heterogeneity^b	Risk of bias^c
1	Terkawi et al., 2015 [12]	21	1714	p < 0.00001	Medium	High	Moderate
2	Albrecht et al., 2015 [13]	18	566	p < 0.00001	Large	High	High
3	Baeriswyl et al., 2015 [16]	18	886	p < 0.00001	Large	High	Moderate
4	Lewis et al., 2015 [17]	18	1807	p < 0.00001	Large	Low	Moderate
5	Chan et al., 2014 [20]	9	416	p = 0.00007	Large	Moderate	Moderate
6	Svircevic et al., 2013 [24]	31	2877	p = 0.72	̶	̶	̶
7	Ong et al., 2005 [26]	13	653	p = 0.002	Medium	High	Moderate
8	Richman et al., 2006 [27]	14	NA	p < 0.00001	Medium	NA	NA

^aDegree was graded as small, medium, or large according to Sullivan and Feinn [6]
^bDegree was graded as low, moderate, or high [7]
^cThe authors’ of respective meta-analysis conclusion, based on the Cochrane Collaboration principles [8], graded as high, moderate, or low

ISSN: 1471-2253