title: To cause or not to cause? That is the question, but identical twins might not have all of the answers.
authors.affiliation: University of Colorado, Boulder, CO, United States. Electronic address: boardman@colorado.edu.
authors.forename: Jason D
authors.initials: JD
authors.lastname: Boardman
authors.affiliation: University of Wisconsin, Madison, United States.
authors.forename: Jason M
authors.initials: JM
authors.lastname: Fletcher
mesh_terms: D015984:Causality; D015986:Confounding Factors, Epidemiologic; D004522:Educational Status; D059647:Gene-Environment Interaction; D005838:Genotype; D054624:Health Status Disparities; D006801:Humans; D064890:Social Determinants of Health; D018433:Twin Studies as Topic / Q000592:standards*; D014430:Twins, Monozygotic
keywords: Causal estimates; Health and education; Identical twins