TABLE 1.

Variables and categories used to characterize students’ reasoning on pedigree problems (a complete version including code descriptions and examples can be found in the Supplemental Table 1)

Variable	Categories
Type of statement	Description
	Allegation
	Clue
	Proof
	Other
Pedigree feature	Phenotypic family constellation
	Genotypic family constellation
	Proportion of affected persons
	Gender ratio among affected
	Distribution of affected over generations
	Pedigree size or structure
	Other
	Missing
Claim	Autosomal dominant
	Autosomal recessive
	X-linked dominant
	X-linked recessive
	Autosomal
	X-linked
	Y-linked
	Dominant
	Recessive
	Other
Orientation	Confirmation
	Refutation
Conclusiveness	Conclusive
	Indeterminable
	Inconclusive