The psychometric properties of the Disease Perception Questionnaire

Abstract

This article describes the psychometric properties of the Disease Perception Questionnaire (Kwestionariusz Obrazu Choroby, KOCh, in Polish). An original version of KOCh consisting of 99 items was used to survey a group of 161 subjects aged 25 to 85 years. On the basis of factor analysis, four factors (scales) were identified which pointed to the subjects’ different perceptions of their disease: (1) Disease as a Threat, (2) Disease as a Weakness, (3) Disease as a Task, and (4) Disease as a Benefit. Items with the lowest factor loadings and the lowest factor specificity indexes were rejected. The factors identified explained 38% of the total variance. The final version of the KOCh questionnaire consisted of 57 items. The coefficients of reliability for the individual factors were Cronbach’s alpha = 0.94 for Disease as a Threat, Cronbach’s alpha = 0.86 for Disease as a Weakness, Cronbach’s alpha = 0.84 for Disease as a Task, and Cronbach’s alpha = 0.85 for Disease as a Benefit.