Background. Empathy plays a key role in social understanding, but its empirical measurement has proved difficult. The Empathy Quotient (EQ) is a self-report scale designed to do just that. This series of four studies examined the reliability and validity of the EQ and determined its factor structure.

Method. In Study 1, 53 people completed the EQ, Social Desirability Scale (SDS) and a non-verbal mental state inference test, the Eyes Task. In Study 2, a principal components analysis (PCA) was conducted on data from 110 healthy individuals and 62 people reporting depersonalisation (DPD). Approximately 1 year later, Study 3, involved the re-administration of the EQ (n=24) along with the Interpersonal Reactivity Index (IRI; n=28). In the last study, the EQ scores of those with DPD, a condition that includes a subjective lack of empathy, were examined in depth.

Results. An association was found between the Eyes task and EQ, and only three EQ items correlated with the SDS. PCA revealed three factors: (1) ‘cognitive empathy’; (2) ‘emotional reactivity’, and (3) ‘social skills’. Test–retest reliability was good and moderate associations were found between the EQ and IRI subscales, suggesting concurrent validity. People with DPD did not show a global empathy deficit, but reported less social competence.

Conclusions. The EQ is a valid, reliable scale and the different subscales may have clinical applications.