A Bistable View of Single Constructs Measured Using Balanced Questionnaires: Application to Trait Anxiety.

Single constructs measured using positively and negatively worded items are often incompatible with a congeneric model, but require 2 correlated factors. Imperfect correlation entails that 2 independent dimensions are required for representing the true variance. If 2 dimensions are sought, how can they be interpreted? This study shows how to extract a group factor orthogonal to the common factor, from either the positive or the negative variables. Applied to trait anxiety measured using the State–Trait Anxiety Inventory (STAI), the approach generates a bistable view of the construct, stressing basic definitional ambiguity.