Table 2 Summary of the systematic reviews characteristics
|  | Total SRs (n = 49) | SRs of RCTs (n = 20) | SRs of NRSs (n = 15) | SRs of RCTs/NRSs (n = 14) |
|---|---|---|---|---|
Number of primary studies, median (range) | 19 (5–104) | 22 (5–90) | 20 (7–104) | 19 (5–61) |
Number of participants, median (range) | 4222 (484–2,791,732) | 4253 (484–16,990) | 14,550 (1394–2,791,732) | 2958 (708–8163) |
Summary of findings table, n | 39 | 17 | 11 | 11 |
Meta-analysis conducted, n | 46 | 20 | 13 | 13 |
Outcomes rated in a SR, median (range) | 8 (1–184) | 5 (1–249) | 5 (1–78) | 5 (1–68) |
Category | ||||
 Clinical therapy, n | 22 | 8 | 7 | 7 |
 Drug, n | 14 | 10 | 1 | 3 |
 Specific clinical disease, n | 6 | 0 | 4 | 2 |
 Lifestyle factors, n | 3 | 0 | 3 | 0 |
 Supplements, n | 2 | 1 | 0 | 1 |
 Clinical approach, n | 1 | 0 | 0 | 1 |
 Clinical care, n | 1 | 1 | 0 | 0 |