The Five-Factor Model organizes human personality traits under a comprehensive framework of five dimensions–neuroticism, extraversion, openness to experience, agreeableness and conscientiousness. The dimensions are empirical generalizations of enduring differences in behavioural, emotional and cognitive patterns between individuals. The Portuguese version of the NEO-Five Factor Inventory (NEO-FFI-20) is increasingly used as it is the shortest version to evaluate the “Big 5”.

To investigate the reliability and the validity of the Portuguese version of NEO-FFI-20-item (Bertoquini & Pais Ribeiro) in a Portuguese sample, using exploratory and confirmatory factor analysis (EFA and CFA).

747 participants [417 (55.8%) women; mean age = 42.13 ± 12.349 years] answered an online survey which included the NEO-FFI-20 and socio-demographic questions. The total sample was randomly divided in two sub-samples (sample A, n = 373; sample B, n = 374). Sample A was used to EFA and sample B was used to CFA.

The Portuguese version of NEO-FFI-20, excluding items 14 and 16, had an acceptable fit to the data (χ2/df = 2.28; TLI = .88; CFI = .90; RMSEA = .06; P = .059). The internal consistency analysis resulted in: Neuroticism, α = .68; Extraversion, α = .62; Openness to Experience, α = .74; Agreeableness, α = .70; and Conscientiousness, α = .74.

The NEO-FFI-20 can be used to reliably and validly evaluate the BIG FIVE in an ongoing research project on traffic psychology to better understand and respond to risky behaviours on the road.

The authors have not supplied their declaration of competing interest.