THE FACTOR STRUCTURE OF THE ADULT PSYCHIA TRY MORBIDITY QUESTIONNAIRE(QMPA) IN A COMMUNITY SAMPLE OF BRAZILIAN CITIES

Principal Components Analysis is a multivariate statistical technique for the purpose of examining the interdependence among variables. The main characteristic of this technique is the ability to reduce data, a nd it is currently used as an adjunct for the development of psychiatr ic research tools and the classification of psychiatric disorders. It has been applied to the study of the Factorial Structure of a Brazilia n screening questionnaire, the Adult Psychiatric Morbidity Questionnai re (QMPA). The questionnaire is made up of 45 yes/no items for the ide ntification of psychiatric symptons and the use of psychiatric service s and psychotropic drugs. The questionnaire was applied to 6.470 subje cts over 15 years old in representative samples from three urban areas : Brasilia, Porto Alegre and S. Paulo. Seven factors were found to exp lain 42.7% of the total variance: Anxiety/Somatization (eigenvalue = 3 .81, 10.9%); Irritability/Depression (eigenvalue = 2.41, 6.9%); Cognit ive Impairment (eigenvalue = 2.01, 5.8%); Alcoholism (eigenvalue = 1.9 0, 5.4%); Mood Elation (eigenvalue = 1.62, 4.6%); Hallucinatory/Delusi onal Disorders (eigenvalue = 1.60, 4.6%); and Drug/Therapies (eigenval ue = 1.60, 4.5%). A similar pattern of results was found when the anal ysis was carried out in the three places. It is suggested, on the bani s of these findings, that some questions should be modified and some e xcluded in any future version of the questionnaire.