Developing a Japanese version of the mental pollution questionnaire and examining the cognitions that contribute to mental contamination

Abstract

Mental contamination is the experience of contamination-related feelings of dirtiness despite the absence of direct physical contact with a contaminant. These feelings of dirtiness may be evoked by unwanted thoughts and memories of negative events such as ill treatment or sexual assault. This paper is composed of two related studies. The aim of Study 1 (n = 202 for factor analysis; n = 81 for test–retest reliability) was to develop a Japanese version of the Mental Pollution Questionnaire (MPQ–J), an instrument for measuring mental contamination. The aim of Study 2 (n = 236) was to confirm this instrument’s psychometric properties and to test the hypothesis that cognitions related to responsibility and morality predict feelings of mental contamination. After conducting factor analyses, the final version of the MPQ–J yielded eight items and two subscales. The psychometric properties of the MPQ–J were verified by examining correlations with general psychopathology measures. Hierarchical regression analyses showed that cognitions related to responsibility and morality made unique contributions to MPQ–J scores after controlling for symptoms of contact contamination fears, depression, anxiety and personality traits. In conclusion, individuals with cognitions indicating an inflated sense of responsibility and high moral standards are at greater risk for mental contamination. Clinicians may find this helpful in identifying clients who are at risk for mental contamination.