Table 3 Pairwise contrasts between Cox’s proportional hazard ratio estimates (95% confidence intervals) for mortality over a 28-year period. Hazard ratios were estimated for outcrossed E. globulus (GLxGL) and E. ovata (OVxOV); open-pollinated E. globulus (GLop) and E. ovata (OVop); and selfed E. globulus (GLself) and E. ovata (OVself). The hazard ratio is an indication of the relative probability of mortality of the first treatment group per unit of time compared to the second control group in each comparison. The significance of the observed hazard ratio was tested using the non-parametric log-rank test between the pairwise contrasts
Contrast | Hazard ratio | Confidence interval | Log-rank test (df = 1) | P value |
|---|---|---|---|---|
GLself-GLxGL | 2.48 | 1.90–3.23 | 48.0 | < 0.001 |
GLop-GLxGL | 1.35 | 1.07–1.68 | 6.72 | 0.010 |
OVself-OVxOV | 3.43 | 2.33–5.05 | 44.2 | < 0.001 |
OVop-OVxOV | 1.36 | 1.11–1.67 | 8.9 | 0.003 |
OVxOV-GLxGL | 2.09 | 1.67–2.61 | 43.9 | < 0.001 |
OVop-GLop | 1.92 | 1.55–2.37 | 38.1 | < 0.001 |
OVself-GLself | 1.70 | 1.15–2.53 | 7.1 | 0.008 |