Table 3.
Frequency of different judgments for the same supporting explanation related to percent of attrition in RCT groups and comments about statistics
| Supporting explanation n = total number of Cochrane reviews that had this supporting explanation N = number of analyzed Cochrane reviews |
Risk of bias judgment | ||
|---|---|---|---|
| Low, N (%) | Unclear, N (%) | High, N (%) | |
| Percent of attrition in the RCT groups with higher attrition | |||
| Attrition between the groups was under 10%, n = 264, N = 122 | 101 (82.8) | 16 (13.1) | 5 (4.1) |
| Attrition between the groups that was 10–20%, n = 354, N = 143 | 91 (63.6) | 28 (19.6) | 24 (16.8) |
| Attrition between the groups that was 21–30%, n = 215, N = 60 | 34 (56.7) | 5 (8.3) | 21 (35) |
| Attrition between the groups that was above 30%, n = 276, N = 70 | 18 (25.7) | 9 (12.9) | 43 (61.4) |
| Supporting explanations about statistics | |||
| ITT analysis used, n = 825, N = 193 | 140 (72.5) | 21 (10.9) | 32 (16.6) |
| ITT analysis was not used, n = 238, N = 35 | 20 (57.1) | 9 (25.7) | 6 (17.1) |
| PP analysis used, n = 81, N = 8 | 7 (87.5) | 1 (12.5) | 0 (0) |
| LOCF analysis used, n = 66, N = 25 | 13 (52) | 3 (12) | 9 (36) |
Abbreviations: ITT intention-to-treat, LOCF last observation carried forward, PP per protocol, RCT randomized controlled trial,