Use of the Depression Anxiety Stress Scale-21 in young people with temporomandibular disorders: Reliability and dimensionality.

OBJECTIVE: The reliability and dimensionality of the Depression Anxiety Stress Scale-21 (DASS-21) were explored in adolescents/young adults with temporomandibular disorders (TMDs).

METHODS: TMD presence was established with the Fonseca Anamnestic Index. Reliability of the DASS-21 for participants with (WT) and without (NT) TMDs was assessed by the Cronbach alpha test, while dimensionality was examined using exploratory factor analysis.

RESULTS: Data from 400 participants (mean age 18.8 ± 1.5 years; 52.2% women) comprising 47.0% with and 53.0% without TMDs were evaluated. Total-DASS and the 3 subscales showed acceptable to high internal consistencies for the WT and NT groups, with alphas of 0.78-0.94 and 0.66-0.92, respectively. Although 3 factors contributed to about half the variance for both groups, scalar and item discrepancies in the primary anxiety-stress factor existed.

CONCLUSION: The DASS-21 has good reliability but may comprise only 2 dimensions, specifically anxiety-stress and depression, instead of the 3 originally asserted.