Peer Effects in Health Behaviors


This article briefly outlines some of the history, empirical challenges, current research and controversies, and directions for the future of peer effects in health behaviors research area. Indeed, it is important to point out that this article being necessarily unexhaustive, does not cover important research areas that share many of the same issues described herein. Perhaps most obvious are the exclusion of the neighborhood effects literature that focuses on health outcomes and the emerging literature that examines potential peer effects in other health related areas such as doctors’ prescribing patterns and medical technology adoption. These important areas are beyond the scope of this article, which focuses only on the peer effects in health behaviors.

Research in the economics literature examining the effects of peers on health behaviors is now more than two decades old. There has been impressive progress as well as a stable set of challenges still not fully resolved. There has been a broadening of the set of behaviors and outcomes under consideration including weight and mental health besides the use of quasi-experimental research designs for additional outcomes of interest. In contrast, the growing volume of data on peer influence, especially online, has not been met by new research designs and methodologies that can produce entirely convincing results. This will be an important challenge to the researchers’ work of expanding the literature on peer effects in health behaviors.


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