Patient Health Questionnaire (PHQ-9)

The Patient Health Questionnaire - 9 Item Version (PHQ-9) is an established diagnostic instrument designed to screen for the presence and measure the severity of depressive symptoms in individuals. This tool is part of the broader Patient Health Questionnaire and hones in on the symptoms specifically associated with major depressive disorder as defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). The PHQ-9 has become an integral component of mental health assessment protocols, valued for its precision and straightforward approach in both clinical and research settings.

Respondents of the PHQ-9 are asked to reflect on their experiences over the past two weeks, rating the frequency of symptoms such as sleep disturbance, loss of interest, energy levels, and mood changes. Each of the nine items on the questionnaire corresponds directly to one of the DSM-5 criteria for major depressive disorder, ensuring that the assessment is closely aligned with recognized diagnostic standards. This alignment facilitates a more accurate assessment of depression, aiding clinicians in distinguishing between normal psychological fluctuations and clinically significant depressive conditions that require intervention.

The structure of the PHQ-9 is notably concise, which allows for quick administration and scoring. Each item is rated on a four-point scale from “not at all” to “nearly every day,” making it possible for healthcare providers to quantify the severity of depression based on cumulative scores. This quantitative approach not only supports a rapid initial assessment but also enables ongoing monitoring of symptom changes over time, crucial for evaluating the effectiveness of treatment approaches.

In practice, the PHQ-9’s brevity and ease of use make it particularly useful in primary care settings where time and resources may be limited. Its widespread acceptance and use is supported by extensive validation studies that confirm its reliability and validity across diverse populations and various healthcare environments. The PHQ-9 facilitates early detection and appropriate management of depression, ultimately contributing to improved patient outcomes and more efficient use of healthcare resources.

The Patient Health Questionnaire - 9 Item Version continues to be a useful tool in the identification and management of depression, offering healthcare providers a reliable, efficient, and validated method for evaluating depression severity. Its integration into routine clinical practice continues to enhance the quality of care for patients experiencing depressive disorders, supporting timely and informed clinical decisions.

Over the past 2 weeks, how often have you been bothered by any of the following problems?

  Not At All Several Days More Than Half The Days Nearly Every Day
1. Little interest or pleasure in doing things.
2. Feeling down, depressed or hopeless.
3. Trouble falling asleep, staying asleep, or sleeping too much.
4. Feeling tired or having little energy.
5. Poor appetite or overeating.
6. Feeling bad about yourself - or that you’re a failure or have let yourself or your family down.
7. Trouble concentrating on things, such as reading the newspaper or watching television.
8. Moving or speaking so slowly that other people could have noticed. Or, the opposite - being so fidgety or restless that you have been moving around a lot more than usual.
9. Thoughts that you would be better off dead or of hurting yourself in some way.
  1. Kroenke K, Spitzer, RL, & Williams JB. The PHQ-9: validity of a brief depression severity measure. Journal of General Internal Medicine, 16(9), 606-613. (2001).