"The Eysenck Personality Questionnaire – Revised (EPQ-R) and the Eysenck Personality Profiler (EPP) are designed to measure the three traits of extraversion, neuroticism and psychoticism. In addition both contain a scale to measure socially desirable responding. The EPQ-R contains just these scales, the EPP measures facets of the personality scales. Both scales are available in long and short forms, the long form of the EPQ-R comprising 100 items, the short form 48 items. For the EPP the long form contains 440 items, the short form 200 items. The tests were developed by Hans Eysenck and his co-workers (principally Sybil Eysenck) over a 40 year period from 1952 to 1992, beginning with the Maudsley Medical Questionnnaire (MPQ; 1952), the Maudsley Personality Inventory (MPI; 1952), the Eysenck Personality Inventory (EPI; 1964), the Eysenck Personality Questionnaire (EPQ; 1975 – this scale included psychoticism for the first time), the Eysenck Personality Questionnaire – Revised (1985) and the Eysenck Personality Profiler (1992). The developments of the scales matched Eysenck’s theory about the underlying structure of personality, and its biological or anatomical underpinnings. Eysenck always attempted to pin individual differences to differences in brain or nervous system structure. In the case of extraversion, there has been some considerable success, but as yet there has been little success in finding biological correlates of neuroticism and psychoticism. The EPQ has been, and continues to be, widely employed in psychological practice and research. It has been translated into a number of languages, and support has been found for the factor structure in many different cultures and languages."