Testing for elevated disease rates using smoothed estimates.

A method of testing for elevated disease rates using smoothed estimates is introduced for counts aggregated to a specific administrative level. A test statistic is developed based on an approximation to the smoothed estimate from a penalized multinomial likelihood and an approximate critical value is derived. Empirical investigation reveals that smoothing can increase the ability to detect elevated rates. The methods are applied to data on gastric cancer in Nova Scotia, Canada.