[Psychiatric diagnosis: personalised by definition]

Personalised psychiatry requires a psychiatric diagnosis which aims to determine the causes of the mental disorder and the context within which it has developed, including the factors of most importance for the choice of an appropriate treatment.

To show that psychiatric diagnosis is personalised by definition.

Description of the differences between psychiatric classification and psychiatric diagnosis, including a discussion of symptom network diagnosis and diagnosis of meaningful connections.

It appears from references from classical and recent psychiatric textbooks and from the recent Dutch Guideline for psychiatric evaluation that psychiatric diagnosis, different from classification, has always been aimed at determining both biological and psychosocial etiological and pathogenic factors and factors influencing the course and the treatment of the disorder.

A personalised approach in psychiatry may lead to a direly necessary reappraisal of psychiatric diagnosis that is not limited to the classification of symptoms, but that aims specifically towards explaning and understanding mental illness.