title: Splitting the differences: problems in using twin controls to study the effects of BMI on mortality.
authors.forename: Jay S
authors.initials: JS
authors.lastname: Kaufman
authors.forename: M Maria
authors.initials: MM
authors.lastname: Glymour
mesh_terms: D015992:Body Mass Index; D005260:Female; D006801:Humans; D008297:Male; D008962:Models, Theoretical; D009026:Mortality; D015983:Selection Bias; D018433:Twin Studies as Topic; D014427:Twins / Q000235:genetics*