Time-to-event
has become one of the primary endpoints of many clinical trials. Comparing treatments
and therapies using time-to-event (or “survival”) data requires some care, since
survival differences may occur either early or late in the follow-up period, depending
on various factors such as the initial potency or the duration of efficacy of
the drugs. In this work, we investigate the effect of the CIMAvax?EGF
vaccine therapy on the survival of patients with non-small cell lung cancer, using
stratified and unstratified weighted log-rank tests. Weighted log-rank tests are
designed to identify early and late survival differences
between treatments. Using these tests, we conclude that the vaccine is more
efficient than the standard therapy among patients less than 60 years of age.
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