Fig. 2.

 Example process of stepwise cluster formation. Publications from a literature search and those from companyʼs database including also abstracts and reports were pooled in the first step and reviewed for availability of data for STW 5 and single plant extracts. In several steps a tabulation of single pharmacological data and corresponding effect sizes was performed considering a variety of subgroups (e.g., laboratory tests, animal systems, location, etc.). All single test data were pooled in the first order cluster level for the two FD subgroups and IBS. These groups were further combined in second order cluster level (gastric accommodation [FD-EPS], inflammation [FD-PDS], or intestinal motility [IBS]). As shown in Table 1 , all subgroups for the FD subgroups and IBS are each combined in third order cluster level as shown in Tables 4S, 5S , and 6S (Supporting Information). Overall mean in before-mentioned tables is the fourth order cluster level result for FD-EPS, FD-PDS, and IBS.