Cognitive factors, such as the accessibility of schematic categories, have been shown to bias interpretation of information about other's behaviour. In this study, the effects of diagnostic category accessibility on subjects' causal attributions for an interviewee's behaviour were investigated. In order to activate a specific diagnostic category, making it more accessible for information encoding, mental health students completed a short test. Half answered questions about victims of rape attacks; the other half answered questions about the diagnosis of histrionic personality disorder. All subjects then rated their attribution for a female interviewee's non-verbal behaviour along four dimensions: Internality, Stability, Globality, and Controllability. Results indicated an interaction between type of course and experimental condition. Psychology undergraduate students in the Rape Victim condition tended to make more stable and global attributions than did Psychiatric Nursing and Masters of Psychological Medicine students. In addition, a significant main effect was found on the Controllability dimension. The subjects in the Personality Disorder condition rated the cause as significantly more controllable than did the subjects in the Rape Victim condition. Implications of the results are discussed.