The meaning of confidence intervals

Every time we need to know the value of a variable in a population we have to estimate it from data obtained from samples drawn from that population. Confidence intervals allow us to approximate, once calculated the value of the variable in the sample, to the range of values that includes the unreachable actual variable value in the population, always within a degree of uncertainty that we can determine.

Moreover, confidence intervals provide additional information that is usually lost when we only assess statistical significance, allowing us to study the accuracy of the estimate variable and the clinical relevance of the results.