Digman (1997) found that the Big 5 personality factors are inter-correlated forming two higher-order factors: Alpha consisting of Agreeableness, Conscientiousness and Emotional Stability, and Beta consisting of Extraversion and Openness to Experience. Musek (2007) found that these higher-order factors remain correlated giving a rise to a general factor of personality. In the wake of this land mark article professional opinions polarised concerning the existence and nature of this general factor.

A group of N=250 A-level students completed a 30 scale personality measure with a 5 point Likert response scale. The first unrotated principal component (FUPC) accounted for 20% of the variance showing negative valence for Modest, Traditional, Worrying and Emotional Control scales. An alternative approach is the deployment of the Great 8 competencies of Kurz & Bartram (2002) that extends the academically accepted Big 5 personality factor model by separating out Need for Achievement from Conscientiousness, Need for Power from Extraversion and Analysis from Openness to Experience. The FUPC of the 8 higher-order scales accounted for 38% of the variance with positive valence for all constructs. The overall construct correlations were at a minimum .97 suggest high overlap of the methods.

The results suggest that Total scores are preferable to the FUPC as they provide a simpler explanation of the overall score and enable differential profiling at any sub-ordinated level. The paper concludes with an outline how the concepts discussed could enhance clinical measures of personality disorder such as the Millon MCM III.