Table 3 Calculation of non-inferiority margins based on 14 eligible studies
Measure of association | Odds ratio (95% CI) | Risk ratio (95% CI) |
|---|---|---|
Point estimate of current standard of care vs placebo, ‘no treatment’ or ‘less intensive treatment’ | 0.18 (0.14−0.25) | 0.19 (0.12−0.28) |
Reversed point estimate of current standard of care vs placebo, ‘no treatment’ or ‘less intensive treatment’ | 5.56 (4.00−7.14) | 5.26 (3.57−8.33) |
Non-inferiority margins | Odds ratio based on arithmetic/geometric scale | Risk ratio based on arithmetic/geometric scale |
Limit for no preserved effect | 4.00/4.00 | 3.57/3.57 |
Threshold for preservation of 50% of effect | 2.50/2.00 | 2.29/1.89 |
Threshold for preservation of 66% of effect | 2.00/1.60 | 1.86/1.54 |
Threshold for preservation of 75% of effect | 1.75/1.41 | 1.64/1.37 |
Threshold for preservation of 100% of effect* | 1.00/1.00 | 1.00/1.00 |