Table 1. Population (N=1.000.000) characteristics x1 – x12; outcomes are simulated from a logistic regression model with parameters bi and binti.
For each patient, 12 binary baseline characteristics were independently generated with a prevalence of 20% each. The outcomes of the 500.000 patients in the control arm (average event rate of 25%) are generated from a logistic regression model with associations between baseline characteristics and outcomes according to column 3 (“control arm”). The outcomes for patients in the treatment were first generated from the same logistic regression model (column 4; “treatment arm without true interaction”), but including a main treatment effect odds ratio of either 1 (“null”), 0.8 (“moderate”), or 0.5 (“strong”), respectively. Alternatively the outcomes for patients in the treatment arm were generated from a different logistic regression model (column 6; “treatment arm with interaction”).
| Control arm | Treatment arm without interactions | Treatment arm with interactions | |||
|---|---|---|---|---|---|
| Variable | ORC | ORTR | ORTR / ORC | ORTR | ORTR / ORC |
| x1 | 1 | 1 | 1 | 1 | 1 |
| x2 | 1 | 1 | 1 | 1 | 1 |
| x3 | 1 | 1 | 1 | 1 | 1 |
| x4 | 1.2 | 1.2 | 1 | 1.4 | 1.17 |
| x5 | 1.2 | 1.2 | 1 | 1.2 | 1 |
| x6 | 1.2 | 1.2 | 1 | 1 | 0.83 |
| x7 | 1.5 | 1.5 | 1 | 2 | 1.33 |
| x8 | 1.5 | 1.5 | 1 | 1.5 | 1 |
| x9 | 1.5 | 1.5 | 1 | 1 | 0.67 |
| x10 | 2 | 2 | 1 | 2.5 | 1.25 |
| x11 | 2 | 2 | 1 | 2 | 1 |
| x12 | 2 | 2 | 1 | 1.5 | 0.75 |