highly significantP << 0.001
The comparison with the spontaneous survival time of the cats in the control group [mean survival time 0.8 ? 0.3 months (Table 1), with a maximal survival time of 1.5 months and a median survival time of 0.7 months] shows that the increase in lifespan of the treated cats is highly significant (F = 204 in the Fisher-Snedecor test; P << 0.001).