Depression screening uses short, standardized questionnaires to identify whether someone may have depression. The most widely used tool, the PHQ-9, takes under five minutes to complete and scores symptoms on a scale from 0 to 27. The U.S. Preventive Services Task Force recommends that all adults, including pregnant and postpartum women, be screened for depression as part of routine care.
The Two-Question Screen
Most screening starts with just two questions, known as the PHQ-2. These ask how often, over the past two weeks, you’ve been bothered by: (1) little interest or pleasure in doing things, and (2) feeling down, depressed, or hopeless. Each question is scored from 0 (“not at all”) to 3 (“nearly every day”), giving a total between 0 and 6.
At a cutoff score of 2 or higher, the PHQ-2 catches about 86% of people with major depression. The tradeoff is that it also flags some people who don’t have it, with a specificity of 78%. Raising the threshold to 3 or higher makes it more precise (92% specificity) but misses more true cases. In practice, a positive result on the PHQ-2 simply means the longer screening tool should follow.
The PHQ-9: The Standard Screening Tool
The PHQ-9 expands the two-question screen into nine items, each mapping to one of the core symptoms used to diagnose depression. Over the past two weeks, how often have you been bothered by:
- Little interest or pleasure in doing things
- Feeling down, depressed, or hopeless
- Trouble falling asleep, staying asleep, or sleeping too much
- Feeling tired or having little energy
- Poor appetite or overeating
- Feeling bad about yourself, or that you’re a failure
- Trouble concentrating on things like reading or watching TV
- Moving or speaking noticeably slowly, or the opposite, being fidgety and restless
- Thoughts that you would be better off dead, or of hurting yourself
Each item is scored 0 to 3, producing a total between 0 and 27. The severity breaks down into easy-to-remember ranges: 0 to 4 is minimal, 5 to 9 is mild, 10 to 14 is moderate, 15 to 19 is moderately severe, and 20 to 27 is severe depression. A score of 10 or above is the most commonly used threshold for a positive screen, meaning further evaluation is warranted.
The PHQ-9 is free, available online, and used in clinics worldwide. You can fill it out on paper or digitally, and it doesn’t require a clinician to administer. That said, the score alone is not a diagnosis. It identifies the likelihood and severity of depressive symptoms, which then need to be evaluated in context.
Screening Older Adults
Depression in older adults often looks different. Rather than sadness, it may show up as withdrawal from activities, low energy, memory complaints, or a sense of hopelessness. Standard screening tools can miss these patterns, which is why the Geriatric Depression Scale (GDS-15) was designed specifically for this population.
The GDS-15 uses 15 yes-or-no questions that avoid physical symptoms (which could overlap with normal aging or other medical conditions). It asks things like “Have you dropped many of your activities and interests?”, “Do you feel that your life is empty?”, “Do you often feel helpless?”, and “Do you feel full of energy?” A score of 0 to 5 is considered normal. Anything above 5 suggests depression and should prompt further evaluation. The simple yes/no format makes it easier for people with cognitive difficulties to complete.
What a Positive Screen Actually Means
A positive depression screen is not a diagnosis. It’s a signal that something needs a closer look. The formal diagnostic criteria for major depressive disorder require five or more of nine specific symptoms to be present most of the day, nearly every day, for at least two weeks. At least one of those five must be either depressed mood or loss of interest in activities. The other symptoms include significant weight or appetite changes, sleep disruption, observable changes in physical movement, fatigue, feelings of worthlessness or excessive guilt, difficulty thinking or concentrating, and recurrent thoughts of death.
A clinician evaluating a positive screen will consider whether these symptoms represent major depression, a different condition (like thyroid problems, grief, or medication side effects), or a temporary response to a stressful situation. This diagnostic step matters because the right next step depends on what’s actually going on.
What Happens After a Positive Screen
When a screening comes back positive, the follow-up typically involves one or more of the following: a referral to a mental health provider (psychiatrist, psychologist, therapist, or clinical social worker), a behavioral health evaluation, psychotherapy, or in some cases medication. The goal is to move from screening into an actual treatment plan, not just to flag a number and move on.
If you screen positive at a primary care visit, your doctor may do additional assessment during the same appointment or refer you to someone who specializes in mental health. Some practices connect patients to depression management programs, group therapy, or support groups. The specific path depends on severity. Someone scoring in the mild range might start with therapy alone, while someone in the moderately severe or severe range may benefit from a combination of therapy and medication.
Screening for Suicide Risk
When depression screening reveals thoughts of death or self-harm, a separate suicide risk assessment is standard. The ASQ (Ask Suicide-Screening Questions), developed by the National Institute of Mental Health, uses four direct questions:
- In the past few weeks, have you wished you were dead?
- In the past few weeks, have you felt that you or your family would be better off if you were dead?
- In the past week, have you been having thoughts about killing yourself?
- Have you ever tried to kill yourself?
If the answer to any of these is yes, a fifth question asks whether the person is having thoughts of killing themselves right now. A “yes” to that fifth question indicates imminent risk requiring immediate safety planning. A “yes” to any of the first four but not the fifth identifies potential risk that still needs follow-up, but is less acute. These questions are deliberately blunt because research consistently shows that asking about suicide does not increase risk. It opens a door that may not otherwise get opened.
How Often to Screen
The USPSTF recommends depression screening for all adults 18 and older but doesn’t specify an exact interval. In practice, many primary care offices screen annually or at wellness visits. People with risk factors, such as a personal or family history of depression, chronic illness, recent major life changes, or the postpartum period, may benefit from more frequent screening. If you’ve had depression before, periodic self-screening with the PHQ-9 can help you catch a recurrence early, before symptoms become entrenched.