title: Note on the interpretation of interactions in comparative research.
abstract: In comparative research it is often the case that attention centers around the existence of an interaction between subject population and an experimental manipulation. Several recent investigators have discussed problems in the interpretation of such interactions. The present paper concerns one particular conceptual difficulty that, although common in research of this type, has received little attention. It was pointed out that dependent variables that are only ordinally related to the construct for which they are a measure are subject to transformations that may create or eliminate statistical interactions.
mesh_terms: D002648:Child; D006801:Humans; D008607:Intellectual Disability; D011584:Psychology; D012106:Research; D013223:Statistics as Topic