Question: Question linked to image nº17 The following figure describes the survival function of the variable progression free of disease (Progression-free Survival, PFS) by the Kaplan-Meier method of two groups of patients. Group A: patients treated with the best support treatment (Best Suportive Care, BSC). Group B: patients who in addition to BSC receive Panitumumab. Data complementary to the figure: patients with disease progression: Group A = 184/232 (79%), Group B = 161/231 (70%). Percentage of censures: Group A = 24/232 (10%), Group B = 38/231 (16%). Log-rank test p <0.0001. Hazard Ratio [95% CI]: 0.54 [0.44-0.66]. Which of the following statements is correct: 
 Options:  <1> The gain in terms of the median time to progression in Group B does not exceed two weeks in relation to Group A. <2> To interpret the results of these two survival curves, it is necessary and sufficient to evaluate and contrast the percentages of progression, that is, 79% in Group A versus 70% in Group B. <3> The ratio of medians in time to progression of the two treatment groups is 0.54. <4> The log-rank test evaluates the average difference in the follow-up time. <5> The results of the log-rank test and the Hazard Ratio estimate (95% confidence interval, 95% CI), are not compatible since the first one indicates that the differences are significant while the second indicates that they are not.
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