Figure 1.
Flow diagram of the study selection procedure.
*One study was identified after the systematic search through March 2009.
Table 1.
Overview and characteristics of included studies.
Figure 2.
The net FMD responses are expressed against their respective precisions (1/SE) in 15 study arms. The net responses are scattered around the pooled overall effect of 2.6% (dotted line). In case the most extreme outlier (red circle) is excluded from the analyses, the net responses are more symmetrically scattered around the adjusted pooled overall effect of 2.4% (red dotted line).
Figure 3.
The net FMD responses and 95% confidence intervals of 15 study arms from 9 studies investigating the effect of tea on FMD are shown. The dotted line indicates the pooled overall FMD effect (2.6%), in which each study arm was weighed by the inverse of its variance (1/SE2). In case of multiple study arms, the intervention is specified between brackets.
Table 2.
Effect of tea on FMD within and between different subgroups.