P-value and statistical significance

What it is

A result with a p value above 0.05 is not statistically significant, which is read as no association between the intervention and the outcome. A result with a p value below 0.05 is statistically significant.

How it is read off a confidence interval

A 95% confidence interval means we are 95% confident that this factor has a higher or lower risk than the other one.

The width gives the precision. A narrow interval means more precise results, as in 49% (39%-58%). A wide interval means less precise results, as in 49% (29-68%).

Whether the range contains 1 gives the significance: if the range contains 1 the results are not significant. So (0.8-1.03) is not significant and (1.05-2.1) is significant.