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] |