Development and validation of a self-reported questionnaire on users' opinions about schizophrenia: a participatory research.

Background: Although users' involvement in mental health research has repeatedly been acknowledged as having a positive influence on research quality, this rarely happens.

Aims: To develop and validate a Questionnaire on Users' Opinions (QOU) about schizophrenia, in close collaboration with 279 persons affected by this disorder.

Methods: A preliminary list of items concerning the opinions of users with schizophrenia regarding causes, treatments and psychosocial consequences of the disorder was developed by 38 users with schizophrenia and 40 professionals who attended a workshop.