Portuguese version
Simões. M. R. & Firmino, H. (2013). Geriatric Depression Scale (GDS-30). Laboratório de Avaliação Psicológica e Psicometria (PsyAssessmentLab), Faculdade de Psicologia e de Ciências da Educação da Universidade de Coimbra.
Barreto, J., Leuschner, A., Santos, F., & Sobral, M. (2008). Escala de depressão geriátrica: Tradução portuguesa da Geriatric Depression Scale. In A. Mendonça, M. Guerreiro & Grupo de Estudos de Envelhecimento Cerebral e Demência (Eds.), Escalas e testes na demência (2.ª ed.; pp. 37-43) [Scales and Test in Dementia, 2nd ed]. GEECD/Novartis.
Original version
Yesavage, J. A., Brink, T. L., Rose, T. L., Lum, O., Huang, V., Adey, M., & Leirer, O. (1983). Development and validation of a geriatric depression screening scale: A preliminary report. Journal of Psychiatric Research, 17, 37-49. https://doi.org/10.1016/0022-3956(82)90033-4.
Theoretical background
The GDS-30 is an instrument specifically developed for use in the elderly population, which combines easy-to-use administration and response format, easy-to-read items and time savings. Psychometric studies indicate reliability, validity, sensitivity and specificity of scores in the evaluation of depressive symptomatology. The GDS-30 enjoys wide acceptance in clinical and research settings.
Description
Assessment Domain: Cognitive and affective.
Type of Instrument: Self-report questionnaire.
Application: Individual, 5-7 minutes.
Population: Elderly.
Dimensions
The GDS-30 is composed of 30 items that have two possible answers (“Yes” / “No”) with two domains: cognitive and affective. The total score ranges from 0 to 30 points: 0-10 points (absence of depressive symptoms) or 11-20 points (mild depressive symptoms) or 21-30 points (severe depressive symptoms).
Studies
The use of Rasch models allowed us to conclude that, regarding infit values, none of the 30 items presented moderate or severe misfit and that, regarding outfit values, only two items presented moderate misfit. Regarding statistics on Items and People, it is important to note the high values observed in Item Separation Reliability (ISR = .99) and Person Separation Reliability (PSR = .85) and in Cronbach's Alpha = .91 (Simões, Prieto, Pinho, & Firmino, 2017).
The scores on the GDS-30 differentiate well a normative community sample (N= 1114; M= 8.6; SD=5.9), a sample diagnosed with Cognitive Decline (N= 274; M= 15.4; SD=7.5) and a sample diagnosed with depression (N=100; M=21.3; SD=5.1) (Simões et al., 2017, 2015).
A more recent study based on a community sample (N=850; M age = 57.34 ± 15.20, age range = [25-91]) identified a greater impact of some sociodemographic variables (gender, educational level and professional status) in the GDS-30 scores and makes new normative data available (Freitas, Nogueira, Pinto, Alves, Santana, & Simões, 2021).
The relationship between results on the GDS-30 and the Beck Depression Inventory (BDI-II) was also investigated in a sample of elderly adults (N=31; r= 0.631) (Oliveira-Brochado, Simões, & Paúl, 2014). This result constitutes additional evidence of the concurrent validity of the Portuguese version of the GDS-30.
Funding
Projecto de investigação: Validação de provas de memória e de inventários de avaliação funcional e de qualidade de vida [Research project: Validation of memory tests and functional and quality of life assessment inventories]. Fundação Calouste Gulbenkian (Proc.º 74569; SHD-22 Neurociências) [PI: Mário R. Simões]
Contacts
Mário R. Simões (<simoesmr@fpce.uc.pt>
References
- Freitas, S., Nogueira, J., Pinto, P., Alves, L., Santana, I., & Simões, M. R. (2021). Influence of Sociodemographic Characteristics on Non-Clinical Depressive Symptomatology among Portuguese Population. Sinapse, 21(1), 34-43. https://www.sinapse.pt/files/section/e65_s99_influence_of_sociodemographic_characteristics_on_non_clinical_file.pdf
- Instrumentos e contextos de avaliação psicológica Oliveira-Brochado, F., Simões, M. R., & Paúl, C. (2014). Inventário de Depressão de Beck (BDI-II) [Beck Depression Inventory – BDI-II]. In L. S. Almeida, M. R. Simões, & M. M. Gonçalves (Eds.), Instrumentos e contextos de avaliação psicológica [Instruments and contexts of psychological assessment] (Vol. II; pp. 189-212). Almedina Edições.
- Simões, M. R., Prieto, G., Pinho, M. S., & Firmino, H. (2015). Geriatric Depression Scale (GDS-30). In M. R. Simões, I. Santana & Grupo de Estudos de Envelhecimento Cerebral e Demência (Eds.), Escalas e Testes na Demência (3.ª ed.; pp. 128-133) [Scales and Tests in Dementia, 3rd ed.]. Novartis.
- Simões, M. R., Prieto, G., Pinho, S., Sousa, L. B., & Firmino, H. (in preparation). Geriatric Depression Scale (GDS-30): A Rasch model analysis.
- Simões, M. R., Sousa, L. B., Pinho, M. S., Vilar, M., Prieto, G., & Firmino, H. (2017). Escala de Depressão Geriátrica (GDS) [Geriatric Depressional Scale (GDS)]. In M. M. Gonçalves, M. R. Simões, & L. S. Almeida (Coords.), Psicologia Clínica e da Saúde: Instrumentos de Avaliação [Clinical and Health Psychology: Assessment Instruments] (pp. 219-233). Pactor.
- Simões. M. R. & Firmino, H. (2013). Geriatric Depression Scale (GDS-30). Coimbra: Laboratório de Avaliação Psicológica e Psicometria (PsyAssessmentLab), Faculdade de Psicologia e de Ciências da Educação da Universidade de Coimbra.