Table 4.
Methodological characteristics of test-treatment trials
| Trial Quality Item | Trials, n | (%) |
|---|---|---|
| Randomized sequence allocation | ||
| Adequate | 59 | (57) |
| Inadequate | 2 | (2) |
| Unclear | 42 | (41) |
| Allocation concealment | ||
| Adequate | 38 | (37) |
| Inadequate | 3 | (3) |
| Unclear | 62 | (60) |
| Blinding | ||
| Patients | 5 | (5) |
| Care-providers | 4 | (4) |
| Outcome assessors | 22 | (21) |
| aSingle-blind | 20 | (19) |
| bDouble-blind | 5 | (5) |
| No blinding | 78 | (76) |
| Reporting of primary outcome assessment | ||
| Complete | 53 | (51) |
| Partial | 33 | (32) |
| Absent | 17 | (17) |
| Reporting of participant flow | ||
| Complete | 44 | (43) |
| Partial | 58 | (56) |
| Absent | 1 | (1) |
| Missing data | ||
| Complete | 41 | (40) |
| Attrition ≤10% | 30 | (29) |
| Attrition >10% | 25 | (24) |
| Incomplete, cannot calculate | 4 | (4) |
| Unclear if complete | 3 | (3) |
| Differential attrition | ||
| ≥ 5% between arms | 16 | (16) |
| ≥ 20% between arms | 1 | (1) |
| Intention-to-treat (ITT) | ||
| Patients analyzed as randomized | 72 | (70) |
| Complete or imputed data and analyzed as randomized | 30 | (29) |
| Not conducted | 31 | (30) |
| Inconsistent outcome assessment | 21 | (20) |
| Inappropriate subgroup analysis | 9 | (9) |
| Sample size | ||
| Power calculation reported | 81 | (79) |
| cMedian trial sample size [IQR] | 309 | [153–731] |
| cMedian study arm sample size [IQR] | 166 | [72–297] |
ablinding either patients or care-providers or outcome assessors; bblinding at least two of: patients, care-providers or outcome assessors; cbased on numbers randomized in all 103 trials