What Is a Confidence Interval?
A confidence interval is an estimated range of values which is likely to include an unknown population parameter. The 95% (p-value = .05) is used on this web site.
Confidence Interval for Ranks of Mortality Rates: Ranking health indices is useful for seeing where a geographic area stands in comparison to other areas. However, ranks are inherently random and are dependent on the variability of the rates. Providing ranks and their level of uncertainty (i.e., the confidence intervals) together demonstrates not only the variability of that area's rate but also the variability of closely ranked areas' rates. CI*Rank presents ranked, age-adjusted cancer mortality rates by state, county, and special region in the US. The site also presents confidence intervals for those ranks. Ranked, age-adjusted US mortality rates for other causes of death are also provided, along with the confidence intervals.