The test is an integral part of Cattell's comprehensive theory of individual differences. Cattell also found that there was a third-order level of personality organization that contained just two overarching, top-level factors (Cattell, 1957), but little time has been spent on defining this most abstract level of personality organization. A listing of these traits can be found in the article on the 16 Personality Factor Model. Thus, the 16PF test gives scores on both the five second-order global traits which provide an overview of personality at a broader, conceptual level, as well as on the more-numerous and precise primary traits, which give a picture of the richness and complexity of each unique personality. Then, they discovered the five global (or second-order) factors by factor-analyzing the sixteen primary traits themselves, to find the basic, organizing forces among the sixteen basic traits. The sixteen primary factors were a result of factor-analyzing hundreds of measures of everyday behaviors to find the fundamental traits behind them. From early in his research, Cattell found that the structure of personality was multi-level and hierarchical, with a structure of interdependent primary and secondary level traits (Cattell, 1946, 1957). The questionnaire measures the 16 primary traits, and the Big Five secondary traits, which have become popularized by other authors in recent years. Beginning in the 1940s, Cattell used the new techniques of factor analysis (based on the correlation coefficient) in an attempt to try to discover and measure the fundamental traits of human personality (Cattell, 1946). Cattell, Maurice Tatsuoka and Herbert Eber. The Sixteen Personality Factor Questionnaire (or 16PF), is a multiple-choice personality questionnaire which was developed over several decades of research by Raymond B.

Cattell's 16pf test