Skip to main content

Table 2 Methodological attributes relevant to interpretation of study results from a clinical perspective for 95 randomized questions, by non-inferiority and superiority trials

From: Clinical significance in pediatric oncology randomized controlled treatment trials: a systematic review

Characteristic Non-inferiority trials
(N = 13)
Superiority trials (N = 82)
n %b n %b
Methods
 Expected magnitude of difference identified explicitly as the MCIDc 2 15.4 2 2.4
 Justification for MCIDa
  Clinical relevance 1 50.0 1 50.0
  Methodological 1 50.0 1 50.0
 Delta value
Stated as an absolute difference 13 100.0 78 95.1
 Margin (median, IQR) − 0.10 − 0.10,0.10 0.12 0.10, 0.17
 Time-to-event 12 92.3 69 88.5
 Dichotomous outcome 1 7.7 9 11.5
 Stated as relative difference 0 0.0 7 8.5
  Margin (median, IQR) N/A 0.63 0.60, 2.50
  Time-to-event N/A 6 85.7
  Dichotomous outcome N/A 1 14.3
  Stated as a percentage and ratio 0 0.0 4 4.9
 Anticipated control value stated 10 76.9 63 76.8
 Assumptions in the control group 6 46.2 12 14.6
 Stated
  Results from previous trial or systematic review 5 83.3 11 91.7
  Based on clinical expertise 1 16.7 1 8.3
 Type 1 error (α value)
 Stated 10 76.9 52 63.4
  0.20 0 0.0 1 1.9
  0.10 2 20.0 2 3.8
  0.05 8 80.0 49 94.2
 Sides
 Stated 12 92.3 40 48.8
  One-sided 10 83.3 29 72.5
  Two-sided 2 16.7 11 27.5
 Type 2 error (1 − β value)
 Stated 12 92.3 81 98.8
   < 80% 2 16.7 7 8.6
  80 to 85% 6 50.0 58 71.6
  85 to 90% 1 8.3 7 8.6
   ≥ 90% 3 25.0 9 11.1
Results
 Statistical significance of primary outcome reported via p value 13 100.0 66 80.5
 Confidence intervals/standard error for primary outcome reported 12 92.3 52 63.4
 Treatment effect stated 6 46.2 6 7.3
Discussion (and/or Results)
 Clinical importance of primary outcome discussed 10 76.9 11 13.4
  1. aMCID minimally clinically important difference, IQR interquartile range
  2. bPercentages may not sum to 100% due to rounding
  3. cAssumed to be the delta value from the sample size calculation