APA Dictionary of Psychology

a self-report personality test for use with adolescents and adults. It originally comprised 57 yes–no questions designed to measure two of Eysenck’s dimensions—extraversion and neuroticism—and included a Lie scale intended to detect response distortion. The EPI was revised and expanded following its initial publication in 1963 to become the Eysenck Personality Questionnaire (EPQ), the most recent version of which (the EPQ–R) includes 90 questions and measures the additional personality dimension of psychoticism. [Hans Eysenck and British psychologist Sybil B. G. Eysenck]