Figure 3.
The funnel plot for the test of publication bias. The funnel plot for *2 vs *1 (a), *1/2 vs *1/1 (b), *2/2 vs *1/1 (c), *1/2 + *2/2 vs *1/1 (d), *2/2 vs *1/2 + *1/1 (e).
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