Gotcha! Behavioural validation of the Gullibility Scale

Every year online scams cause substantial emotional and financial adversity. A recently developed self-report measure of gullibility has the potential to provide insight into how individual differences in gullibility are related to susceptibility to scams. The current study investigated the behavioural validity of the Gullibility Scale and explored individual differences expected to be related to this construct. Undergraduate psychology students (N = 219) initially rated example phishing emails, and completed the HEXACO personality factors, Need for Cognition, Need for Closure, Sense of Self, and the Gullibility Scale. After six weeks, they were sent simulated phishing emails. Respondents who clicked on a link within the simulated phishing emails scored significantly higher on the Gullibility Scale compared to those who chose not to click, providing the first evidence for the behavioural validity of the Gullibility Scale. In addition, gullibility was associated with favourable ratings of the example emails, higher levels of emotionality, and a weaker sense of self. These findings provide further clarification of the psychometric properties of the Gullibility Scale and point to its utility in identifying those at risk of being scammed.