What does the "PHQ-9" measure in a mental health assessment?

The PHQ-9, or Patient Health Questionnaire-9, is specifically designed to measure the severity of depression symptoms in individuals. It consists of nine questions that correspond to the diagnostic criteria for major depressive disorder. Each question assesses the frequency of depressive symptoms over the past two weeks, such as low mood, loss of interest or pleasure, changes in appetite, sleep disturbances, fatigue, feelings of worthlessness or guilt, difficulty concentrating, and thoughts of self-harm.

By capturing the range and intensity of these symptoms, the PHQ-9 enables healthcare providers to evaluate how significantly depression is affecting a person's daily functioning and overall quality of life. This information is crucial for diagnosis, treatment planning, and tracking changes over time in response to interventions.

Understanding the role of the PHQ-9 in mental health assessments emphasizes its importance in identifying and managing depression, distinguishing it from other mental health issues like anxiety or social support, which are not the focus of this specific tool.