How many items does the Patient Health Questionnaire (PHQ-9) typically include?

The Patient Health Questionnaire (PHQ-9) consists of nine items, making it an effective tool for screening, diagnosing, and measuring the severity of depression in individuals, particularly in primary care settings. Each item corresponds to a symptom of depression, evaluated over the previous two weeks, allowing practitioners to gain insight into the patient's mental health status. The structure of the PHQ-9 enables healthcare providers to obtain a detailed understanding of a patient's depressive symptoms, facilitating appropriate treatment planning and monitoring. The other options do not represent the correct number of items in the PHQ-9, as they either underestimate or overestimate the scale.