The evaluation of community-based programs poses special design and analysis problems. The present article focuses on two major types of errors that can occur in such evaluations: false positives—incorrectly declaring a program to be effective—and false negatives—incorrectly...

Population-based surveys are of limited utility to estimate rare or low-incidence groups, particularly for those defined by religion or ethnicity not included in the U.S. Census. Methods of cross-survey analysis and small area estimation, however, can be used to provide reliable estimates of...