A Review of Some Individual- and Community-Level Effect Size Indices for the Study of Risk Factors for Child and Adolescent Development

Abstract

This article discusses the computation and application of various epidemiological measures of effect in educational and developmental research. Specifically, epidemiology provides a potentially important perspective for studies identifying risk factors for healthy child development. For example, it allows for the examination of both individual-level risk (the impact of risk factors on individuals experiencing them) and community-level risk (the impact of risk factors on the overall number of cases within a population). In terms of individual-level risk, issues related to the use and interpretation of the risk-ratio, the odds-ratio, and the logistic regression odds-ratio are reviewed. In addition, community-level measures of effect, such as the population-attributable fraction percentage, are examined. Implications of the design methodology (cohort study, case-control study, or representative study) on the choice and use of these measures of effect are discussed. Data from a large-scale ongoing project in developmental epidemiology are presented throughout the article for illustrative purposes.