Perils and pitfalls of high-risk research.

Several issues in the design and interpretation of high-risk depression reseach are described. These include identification of symptoms and syndromes, categorical vs. dimensional scales, aspects of depression to be considered, specificity of effects, use of process measures, and conceptualization of risk and resilience. The aricles in this special section are used to exemplify the need to address these issues in studies of depression risk