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Table 1

Table 2

Table 3M

Figure 1M

Footnotes (Section 5)

4.1 .3 *Only trials in which such comparisons are "unconfounded" are included. By definition, in unconfounded trials one group differs from another only in the treatment of interest: thus, the tamoxifen overview includes trials of tamoxifen plus chemotherapy versus the same chemotherapy alone, but not trials of tamoxifen plus prednisone versus no treatment. (ln trials of chemotherapy, however, prednisone was considered an integral part of the chemotherapy regimen being evaluated, so trials of chemotherapy plus prednisone versus no treatment were included in the chemotherapy overview.)