Abstract
ovariate studies associating the presence of regularly shaped geographic clusters with environmental factors are routinely done using the Circular Scan. However, if the study employs irregular clusters instead, accurate results depend on the generation of a rich family of variants of the primary cluster. We employ climate information to assess the possible spatial dependence on the occurrence of Chagas'' disease irregular clusters in Central Brazil, using a modification of the Spatial Scan Statistic, the Geo-Dynamic Scan. It finds more potentially useful variants of the primary cluster with more desirable covariate values. This information could be useful in Chagas'' disease surveillance.