When we hear the words there
was a significant treatment effect, you would naturally assume that significant means large, important, or
noteworthy. This may be true—but not necessarily. More often than not, significant refers to statistically significant, which means
that the difference between the two groups of patients was statistically
meaningful and unlikely to be random.
Statistical significance is an important
concept. Without measuring the statistical significance of study results in
cancer treatment, it is possible that any effects may not even be real but
rather just chance. However, statistical significance is not enough. Another
medical term—clinically significant—means
“important to patient care.” This is what we are after. If a small effect is
statistically significant, it may still not be large enough for us to care much
about it. Watch out for the word significant,
and assume it’s likely “statistics-speak” and not necessarily the large,
important improvement you might think.