Concepts of disease: their relevance for psychiatric diagnosis and classification

To deal effectively with the understanding, description and classification of mental morbid conditions, we must address the intricate concept of disease, illness or disorder in mental health. To do so, one needs to consider biological, psychological and social frameworks. These levels of analysis can offer avenues for greater understanding of the bases of illness as well as better ways of formulating its description and classification. Conceptual, epistemological and empirical data analyses are relevant and necessary. All these efforts should be aimed at serving and advancing the main purposes of classification and diagnosis, the chief encompassing one being enhancement of clinical care and public health. Although no definition of mental disorder may strictly embrace every condition of concern, some flexible definitional guidelines within a biopsychosocial framework may be helpful for advancing psychiatric nosology.