Variance Composition, Reliability, Validity, and Measurement Invariance of the Toronto Alexithymia Scale-20 in Nonclinical Samples

摘要

Public Significance Statement Evidence was provided showing that the Toronto Alexithymia Scale-20 (TAS-20) may be used as a unidimensional instrument, and that men and women understand the scale in the same way. However, the use of a TAS-20 total score may be more efficacious if the scale were trimmed. The present study extended prior work on the Toronto Alexithymia Scale-20 (TAS-20). The TAS-20 total scale score is commonly used in research in the psychology of men and masculinities and in clinical practice, but most published confirmatory factor analyses (CFA's) do not support this use. Using a sample of 913 men and women, variance composition was assessed, and model-based dimensionality and reliability coefficients were calculated, finding evidence for unidimensionality, which supports the use of the total scale raw score but not that of the subscales, although the model fit was less than desired. Convergent and concurrent evidence was found for the validity of the TAS-20 in men as a unidimensional scale (N = 505) by examining relationships with latent variables of several constructs in the nomological network. An assessment of measurement invariance by gender (men, women) found evidence for metric invariance, indicating that cisgender men and women understand the scale in the same way. It is recommended that the TAS-20 scale developers follow recommended procedures to trim composite measurement scales to improve the psychometric properties (i.e., model fit) of the TAS.