Analysis of the relationship between each covariate (IVF, success or failure of the IVF, type of protocol) and the time between the relapses, in a frailty model
| RR | SD (95% CI) | p Value | |
| IVF | 1.18 | 0.21 (0.78 to 1.78) | 0.430 |
| Success of IVF | 0.56 | 0.40 (0.25 to 1.22) | 0.141 |
| Failure of IVF | 1.67 | 0.23 (1.06 to 2.63) | 0.026 |
| GnRH agonists | 1.35 | 0.24 (0.83 to 2.18) | 0.220 |
| GnRH antagonists | 0.73 | 0.37 (0.35 to 1.53) | 0.409 |
Each line corresponds to one frailty Cox model and is adjusted for patient age at the last relapse before IVF, disease duration at the last relapse before IVF and type of recruitment. For instance, patients with failure of IVF have 1.67-fold increase risk of relapse (95% CI 1.06 to 2.63).
GnRH, gonadotrophin releasing hormone; IVF, in vitro fertilisation.