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Dysfunctional Beliefs and Attitudes About Sleep Scale - 30 (DBAS-30)

Title of the Portuguese Version

Escala de Crenças Disfuncionais sobre o Sono

Original Version

Morin, C. M. (1993)

Portuguese Version

Clemente, V., Allen Gomes, A., & Moutinho dos Santos, J. (2007, 2013, 2022)

General Description

The DBAS-30 is a well-known self-report instrument assessing beliefs and attitudes about sleep and insomnia. The original DBAS-30 comprises 30 items grouped into five conceptual dimensions: misconceptions about the causes of insomnia; misattributions or amplification of the consequences of insomnia; unrealistic sleep expectations; diminished perceptions of control and predictability of sleep; and faulty beliefs about sleep-promoting practices. The instrument contained a 100 mm visual analogue response scale labelled “strongly disagree” on the left end and “strongly agree” on the right end. With the exception of item 23, for which the score is reversed, a higher score indicates a more dysfunctional belief.

In the DBAS-30 European Portuguese version, each item is rated on a 10-point Likert scale, ranging from 0 (strongly disagree) to 10 (strongly agree). This scale includes three factors: Ageing and Hopelessness, Sleep Expectations, and Consequences and Helplessness. The total DBAS and subscales scores are calculated by summing item scores and dividing by the number of items. Higher scores denote stronger dysfunctional beliefs and attitudes about sleep.

  • Clemente, V., Marques, D. R., Miller-Mendes, M., Morin, C. M., Serra, J., & Allen Gomes, A. (2023). The Dysfunctional Beliefs and Attitudes about Sleep Scale: Dimensions of the European Portuguese DBAS-30 and development of a new short version (DBAS-SF-16). Sleep Medicine, 106, 59-68. https://doi.org/10.1016/j.sleep.2023.03.021 [Published online: 24/03/2023].

  • Morin, C. M. (1993). Insomnia: Psychological assessment and management. New York: Guilford Press.


Vanda Clemente – vandaclem@gmail.com