The State-Trait Anxiety Inventory: Shadows and Lights on its Construct Validity

Abstract Past studies on the factor validity of the Trait
subscale of the Spielberger’s State-Trait Anxiety Inventory
(STAI-T) do unanimously agree on its structure. In fact,
researchers are still debating whether the STAI-T is unidimensional
or multidimensional. Our aim was to clarify what
the STAI-T measures. The STAI-T, the Beck Depression
Inventory–II, the Teate Depression Inventory, and the Beck
Anxiety Inventory were administered to 1124 psychiatric outpatients
and to 877 healthy subjects. A confirmatory factor
analysis was performed in order to compare various models in
the literature. The internal consistency and convergent and
discriminant validity of the STAI-T as well as its factorial
subscales were assessed. The one-construct two-method
(i.e., the STAI-T measures one substantive anxiety construct
plus artifacts due to negative–positive item polarity) and the
bifactor (i.e., the STAI-T comprises two first-order specific
factors [“Anxiety” and “Depression”] and one first-order
general factor) models were the best-fitting solutions for
the STAI–T in both the clinical and nonclinical samples.
The STAI–T total score correlated more strongly with
measures of depression than with a concurrent measure of
anxiety. The STAI-T should be considered a measure of
general negative affect, including specific aspects of cognitive
anxiety and depression together.
Keywords Confirmatory factor analysis . Psychological
tests . Anxiety . Depression . Reliability and validity