Table 2.
Levels of evidence and scoring regime.
| Level of evidence | Combined number of participants in included studies (n = 9263) | No. of studies (n = 76)* | Scoring regime for each publication** |
|---|---|---|---|
| Ia — evidence from meta-analysis of randomized controlled trials | 0 | E = 0 C = 0 |
Evidence levels Ia-III X = 8; Y = 4; Z = 2 |
| Ib — evidence from at least one randomized control trial | 866 | E = 2 C = 10 Total = 12 |
|
| IIa— evidence from at least one controlled study without randomization | 1718 | E = 1 C = 17 Total = 18 |
|
| IIb— evidence from at least one other type of quasi-experimental study (for example one-group, pretest, posttest studies) | 2106 | E = 2 C = 17 Total = 19 |
|
| III— evidence from non-experimental descriptive studies, such as comparative studies, correlation studies and case-control studies | 4570 | E = 3 C = 21 Total = 24 |
|
| IV— evidence from expert committee reports or opinions and/ or clinical experience of respected authorities | 3† | E = 0 C = 3 Total = 3 |
Case or case series reports X = 6; Y = 3; Z = 1 Opinion reports of experts X = 4; Y = 2; Z = 0 |
*Number of reports: E = English, C = Chinese. **Highest ranking publication from each authority = X points; second highest ranking publication from that authority = Y points; each additional publication from that authority = Z points. An authority is defined as the first author of each publication or report. †Two reports at this evidence level comprise expert narration on the benefits of Tai Chi and do not include study participants.