Patient Health Questionnaire Nomenclature and Usage

Introduction to the PHQ Scale

• The Patient Health Questionnaire is formally known as the Patient Health Questionnaire, and it exists in multiple validated versions, each with its own designation, as recognized by the National Comprehensive Cancer Network 1, 2

Common Usage and Validation

• The Patient Health Questionnaire is widely referred to simply as "the PHQ" in clinical practice, with the numeric suffix indicating the number of items included, according to the National Comprehensive Cancer Network and Clinical Infectious Diseases guidelines 1, 2, 3
• The PHQ-9 has become the most frequently utilized depression screening instrument globally, having been translated into more than 70 languages and dialects, as reported by the American Psychiatric Association 4

Important Distinctions and Alternative Screening Tools

• The PHQ should not be confused with other screening tools used in similar contexts, such as the NCCN Distress Thermometer, the Generalized Anxiety Disorder Assessment (GAD-2 or GAD-7), or the Edinburgh Postnatal Depression Scale (EPDS), which are separate instruments used for different screening purposes, as distinguished by the National Comprehensive Cancer Network and Depression and Anxiety guidelines 1, 5