Browse the glossary:
The greater the imprecision, the greater the likelihood of being misled by the play of chance. A confidence interval around an effect estimate is one way of expressing imprecision, with a wider confidence interval meaning more imprecision. Conversely, a narrower confidence interval means more precision and less likelihood of being misled by the play of chance. Imprecision is a reason for there being less certainty of the evidence for an effect estimate.
confidence interval · certainty of the evidence
If you feel that this definition hasn't helped you to understand the term, click on our monkey to let us know.