Psychometric Properties of the 9-Item Shared Decision-Making Questionnaire (SDM-Q-9): Validation of the Italian Version in a Large Psychiatric Clinical Sample.

Objective: The nine-item Shared Decision-Making Questionnaire (SDM-Q-9) is one of the most frequently used tools for assessing patients' involvement in medical decision-making, but so far, it not been validated in Italian. We aimed to validate the Italian version of the SDM-Q-9 in a clinical sample of patients suffering from major psychiatric disorders.

Method: We involved 307 consecutive patients affected by major psychiatric disorders (including schizophrenia spectrum disorders, affective disorders and eating disorders) in a real-world outpatient clinical setting.