Assessing mental disorder causal beliefs: a latent dimension identification.

A Many-Facet Rasch analysis was carried out with the intent of identifying a latent trait dimension characterized by mental disorders causal beliefs variables. The present research consists of two studies. In Study 1, the responses of 443 Italian university students to a 40-item scale were analyzed by means of Rasch models. In Study 2, the responses of two new groups of subjects, of 300 and 135 people respectively, were examined to further validate the mental disorders causal beliefs dimension obtained in Study 1. Specific bias/interactions between the MDCB dimension and other variables, such as gender and university faculties, were detected. Correlation analyses between the MDCB dimension and attribution theory and social desirability variables were also carried out. The results showed that a 30-item Mental Disorder Causal Beliefs (MDCB) latent dimension exists, characterized by contents representative of biological-genetic and psycho-social causes. Males and females did not differ on their causal beliefs, whereas Psychology students presented more psycho-social etiology beliefs. The MDCB dimension was correlated neither to a general locus of control scale nor to the social desirability measure, whereas it was significantly correlated to the psychotherapeutic attribution measure. The results evidenced a well devised measure which can be potentially useful in the research and clinical practice for the assessment of people's etiology beliefs about mental illness, focusing on the development of personalized interventions to reduce or modify eventual negative attitudes and misconceptions.