The progressive increase in the prevalence of anxiety disorders in advanced ages advises the extensive use of of screening measurements in this population, that, everywhere in the world, has raised numerically.

The aim of this study was to examine the psychometric properties of a Portuguese version of the Geriatric Anxiety Inventory-Short Form (GAI-SF, 5-item format) in a sample of 932 elders.

Quantitative and cross-sectional study with descriptive and correlational planning. Translation and back-translation was performed by language proficiency experts. The reliability was assessed through Cronbach's alpha coefficient and the factorial validity through Principal Components Analysis. The convergent validity was conducted with the Geriatric Depression Scale (GDS) and the Positive and Negative Affects Scale (PANAS-Negative sub-scale), while discriminant validity was performed with the PANAS-Positive sub-scale and the Satisfaction With Life Scale (SWLS). A Confirmatory Factor Analysis, using a structural equation modeling, was performed to test the fit of the model with the five items.

The GAI-SF showed good internal consistency (α = 0.77), good convergent, and discriminant validity (p < 0.05). The factorial structure presented a single factor that explained 52% of the variance. The model showed a good fit to the data (χ2= 1.233, TLI = 0.997, CFI = 0.999, RMSEA = 0.020).

The GAI-SF, a brief self-report scale, has good validity and reliability, and factorial qualities adequate to measure anxiety symptoms in epidemiological surveys and in geriatric settings.