This is used in descriptive studies in order to indicate the level of confidence that the confidence interval of the estimate produced will contain the true population value. Usually, a confidence level of 95% is used. The concept of confidence intervals is explained further in the section on [[Random variation]].
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This is used in descriptive studies in order to indicate the level of confidence that the confidence interval of the estimate produced will contain the true population value. Usually, a confidence level of 95% is used. The level of confidence is also The concept of confidence intervals is explained further in the section on [[Random variation]].
===Power===
===Power===
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This relates to analytic studies using hypothesis testing in order to detect a difference in a parameter of interest between two groups, and indicates the ability of a study to detect this difference, assuming that a difference of a specified size does exist.
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This relates to the ability to detect a difference in a parameter of interest between two groups, and so relates to analytic studies using hypothesis testing. The power indicates the probability that a study will detect a difference between groups, assuming that a difference of a specified size does exist, at a specified level of confidence. - for example, if