The impact of genetic causation of mental illness on attitudes and beliefs toward the illness

Download data and study materials from OSF

This experiment was fielded as part of a TESS telephone survey. Data and materials for all the studies included on this survey is available here.

Principal investigator:

Jo Phelan

Columbia University



Sample size: 910

Field period: 10/13/2005-2/1/2006


This vignette experiment assesses the impact of genetic explanations for mental illness on beliefs and attitudes about the illness. In a previous study, I found that genetic attributions significantly increased 1) perceived seriousness of the problem, 2) belief that the problem would persist through the person´s life, 3) belief that the person´s sibling would develop a similar problem, 4) belief that the person´s child would develop a similar problem, and 5) social distance from the person´s sibling (Phelan, JC. 2005. "Geneticization of deviant behavior and consequences for stigma:
The case of mental illness." Journal of Health and Social Behavior 46: 307-322.)
This study extends the previous one by examining more nuanced information that might modify the impact of very simple statements about genetic causation such as the ones I tested previously. These "modifying statements" would bear on availability of gene therapy treatment that would modify the person´s genes but not prevent transmission of the gene to offspring; low probability that the problem would be transmitted to offspring; availability of a pre-natal test for genes involved in the problem; and a carrier-status test for adults.


(1) Genetic causation will be related to more stigmatizing scores on each dependent variable. (2) Because the modifying statements pertain to different aspects of the illness (e.g., illness/symptoms in the person; transmissibility; detectability of genes), the statements are expected to affect different sets of outcome variables. No modifying statement is expected to reduce all stigma-related outcomes, because none totally eliminates the role of genes.

Experimental Manipulations

Genetic vs. non-genetic causal attribution for mental illness (schizophrenia or major depression). If the illness is attributed to genetic factors, a modifying statement may also be introduced: availability of gene therapy, low probability of transmission, availability of genetic tests.


Social distance from sibling of ill person, beliefs about the illness (seriousness, chronicity)