Improving the measurement of alexithymia in autistic adults: a psychometric investigation of the 20-item Toronto Alexithymia Scale and generation of a general alexithymia factor score using item response theory.

The study used online convenience samples, not a representative sample of autistic adults; the autistic sample had more females, more college education, later diagnosis, and more current depression or anxiety than expected. Autistic adults self-reported a professional diagnosis, and SPARK did not independently validate those diagnoses. The general population sample was not screened for autism and completed only 16 of the 20 TAS-20 items, so four items were imputed for total-score comparisons. The analysis was cross-sectional, so it could not check whether scores are stable over time or sensitive to change after therapy. The 8-item score does not directly measure externally oriented thinking or difficulty fantasizing, so it may not cover all parts of the original alexithymia idea. The study did not include cognitive or verbal IQ data, so it cannot say how language ability affects these self-report scores. The general population sample did not complete psychopathology or neuroticism measures, so comparisons between groups cannot rule out other mental health differences. Authors say the new score is not a gold standard and should be checked against other measures and populations.

The supplied article text does not include a funding or conflicts-of-interest declaration. The publication types list NIH extramural and non-U.S. government research support.

Do not use the 8-item score as a diagnosis, treatment target, or proof that autism causes alexithymia. It is only a revised way to score questionnaire items, and the authors say it should not be treated as a gold standard.