title: Adaptation to Portuguese of the Depression, Anxiety and Stress Scales (DASS).
abstract: OBJECTIVE
  To adapt to Portuguese, of Portugal, the Depression, Anxiety and Stress Scales, a 21-item short scale (DASS 21), designed to measure depression, anxiety and stress.
  
  
  METHODS
  After translation and back-translation with the help of experts, the DASS 21 was administered to patients in external psychiatry consults (N=101), and its internal consistency, construct validity and concurrent validity were measured.
  
  
  RESULTS
  The DASS 21 properties certify its quality to measure emotional states. The instrument reveals good internal consistency. Factorial analysis shows that the two-factor structure is more adequate. The first factor groups most of the items that theoretically assess anxiety and stress, and the second groups most of the items that assess depression, explaining, on the whole, 58.54% of total variance. The strong positive correlation between the DASS 21 and the Hospital Anxiety and Depression scale (HAD) confirms the hypothesis regarding the criterion validity, however, revealing fragilities as to the divergence between theoretically different constructs.
authors.affiliation: Health Science Research Unit, Higher School of Nursing Dr. Angelo da Fonseca, Coimbra, Portugal. joaoapostolo@eseaf.pt
authors.forename: João Luís Alves
authors.initials: JL
authors.lastname: Apóstolo
authors.forename: Aida Cruz
authors.initials: AC
authors.lastname: Mendes
authors.forename: Zaida Aguiar
authors.initials: ZA
authors.lastname: Azeredo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001007:Anxiety / Q000175:diagnosis*; D003863:Depression / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007802:Language; D008297:Male; D008875:Middle Aged; D011174:Portugal; D011581:Psychological Tests; D013315:Stress, Psychological / Q000175:diagnosis*; D011795:Surveys and Questionnaires