Factor analysis: an application of the 12-item version of the Goldberg general health questionnaire

Abstract

To explore the factor structure of the 12-item version of the Goldberg General Health Questionnaire with Likert scoring, within persons discharged from treatment and rehabilitation programs for drug abuse related problems, in Chilean care centers. Material and Methods:  A cross-sectional descriptive study was carried out on a sample of 306 persons who completed the General Health questionnaire. The reliability of the instrument was assessed through an internal consistency analysis. A confirmatory factor analysis was carried out through extraction of the principal components with varimax rotation. Results: The mean age was 30; among the study population 80% were male. The Cronbach.s alpha coefficient was 0,902. Using a 0 to 36 points score, the mean total score in the General Health Questionnaire was 8,5 with a standard deviation of 7,1.  The factor analysis confirmed the bidimensionality of the instrument, and the existence of two latent factors, which together accounted for 60% of the total variance. Conclusions:  The present study showed a high level of reliability and a similar factor structure to that found in studies within other populations. In view of its self-administered character and the promptness to complete it, the use of the questionnaire is strongly recommended for the assessment of self- perception of the mental health status within persons consulting for drug abuse related disorders.