Mad In America

Despite What You’ve Heard, “Schizophrenia” Is Not “80% Heritable”
By Jay Joseph, PsyD

The SKN meta-analysis reproduced the folly of psychiatric twin research more generally, in which researchers overlook or validate obviously false assumptions and then present and interpret data in ways that confirm their strong beliefs in biological and genetic explanations.

The evidence suggests that SKN’s confirmation biases led them to identify in advance a desired/expected schizophrenia heritability range, and then work backward to select, interpret, include, and omit studies to produce a meta-analysis heritability estimate falling within that range. Pre-registration of research has been promoted in the “replication crisis” era to help prevent such misleading practices.

Despite What You’ve Heard, “Schizophrenia” Is Not “80% Heritable” Genetics researchers begin with false assumptions and then present and interpret data in ways that confirm these strong beliefs.