Clinical and Psychometric Validation of the Geriatric Depression Scale (GDS) for Portuguese Elders

The main purpose of this study is the adaptation and psychometric validation of the Geriatric Depression Scale (GDS) for the Portuguese population. The analyses of temporal (alpha ((27 items)) = .995) and internal (.91) consistencies, inter-rater reliability (Kappa = .87), and concurrent (.83) and factorial (3 factor) validities demonstrate that GDS is highly reliable as a screening instrument for geriatric depression. This conclusion was further validated by both discriminant function analysis and diagnostic value testing, which showed a sensitivity of 100%, a specificity of 83%, a positive predictive value of 93%, and a negative predictive value of 100%. The study has also evaluated GDS applicability to clinical assessment and therapeutic intervention with elders suffering from moderate feelings of loneliness linked to recurring suicidal ideation.