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Fig. 2 | BMC Medical Research Methodology

Fig. 2

From: Trial Sequential Analysis in systematic reviews with meta-analysis

Fig. 2

Showing three different group sequential boundaries in a single trial with interim analysis. The Z-value is the test statistic and a |Z| = 1.96 corresponds to P = 0.05; the higher the Z-value, the lower the P-value. This is a historical overview of group sequential boundaries for the cumulative Z-curve in relation to the number of randomised participant in a single trial [19, 32, 33]

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