Depression screening and assessment tools

psychometric outcome used to quantify symptoms of depression

The nine-item Patient Health Questionnaire (PHQ-9) is a depressive symptom scale and diagnostic tool introduced in 2001 to screen adult patients in primary care settings. The instrument assesses for the presence and severity of depressive symptoms and a possible depressive disorder. The PHQ-9 is a component of the larger self-administered Patient Health Questionnaire (PHQ), but can be used as a stand-alone instrument. The PHQ is part of Pfizer's larger suite of trademarked products, called the Primary Care Evaluation of Mental Disorders (PRIME-MD). The PHQ-9 takes less than three minutes to co