If you've ever filled out a mental health questionnaire at a doctor's office, there's a good chance it was one of two forms: the GAD-7 or the PHQ-9. They look almost identical — same layout, same four answer choices, same "over the last 2 weeks" framing — and they're often handed out together on the same clipboard. So it's natural to wonder: what's actually the difference? And if you're checking in on your own mental health, which one should you take?
The short version: the GAD-7 screens for anxiety and the PHQ-9 screens for depression. They're siblings from the same research family, built by largely the same team, and they divide the two most common mental health concerns between them. This article walks through where each one came from, what each one measures, how to decide which to take — and why, in practice, the answer is often "both."
Two Scales, One Family
The resemblance between the GAD-7 and PHQ-9 isn't a coincidence. Both grew out of the Patient Health Questionnaire (PHQ) project — an effort to give primary care doctors fast, validated tools for spotting common mental health conditions without needing a psychiatrist in the room.
The PHQ-9 came first. It was developed by Robert Spitzer, Kurt Kroenke, and Janet Williams, and published in 2001 as the depression module of the broader PHQ. Its nine questions map directly onto the nine diagnostic criteria for major depressive disorder, which is part of why it caught on so quickly in clinics.
The GAD-7 followed in 2006, developed by the same core team — Spitzer, Kroenke, and Williams, joined by Bernd Löwe — and validated in a large primary care study. It applied the same winning formula to generalized anxiety: a handful of plain-language questions, scored on a simple scale, validated against clinical assessment. (For a closer look at how well that validation holds up, see is the GAD-7 accurate.)
Because they share DNA, the two scales work the same way mechanically:
- Same time window: both ask about the last 2 weeks.
- Same answer options: "Not at all" (0), "Several days" (1), "More than half the days" (2), "Nearly every day" (3).
- Same scoring logic: add up the item scores for a total.
- Same cut-point convention: a score of 10 or higher is the standard threshold that warrants a closer look on both scales.
That shared format is deliberate. It means a clinic can hand you both forms and you don't have to relearn anything — and it means your anxiety and depression scores are directly comparable in spirit, even though they measure different things.
What Each One Measures
Here's where they split.
The GAD-7 targets anxiety — specifically the worry-driven pattern of generalized anxiety disorder. Its seven items ask about feeling nervous or on edge, being unable to stop or control worrying, worrying too much about different things, trouble relaxing, restlessness, irritability, and a sense of dread that something awful might happen. Notice the theme: it's all worry and tension, pointed at the future. (We break down each item in the 7 GAD-7 questions explained.)
The PHQ-9 targets depression — the pattern of low mood and lost momentum that defines major depressive disorder. Its nine items cover things like little interest or pleasure in activities, feeling down or hopeless, sleep problems, low energy, appetite changes, feeling bad about yourself, trouble concentrating, moving or speaking noticeably slowly (or the opposite, restlessness), and thoughts of being better off dead or of self-harm. The theme here is loss — of pleasure, energy, self-worth, and drive. The sister site to this one walks through every item in detail in the PHQ-9 questions explained.
One difference deserves special mention: the PHQ-9's ninth question asks directly about thoughts of death or self-harm. The GAD-7 has no equivalent item. That question is one reason the PHQ-9 is treated with particular care in clinical settings — a positive answer prompts immediate follow-up, whatever the total score is.
Side by Side
| GAD-7 | PHQ-9 | |
|---|---|---|
| Screens for | Generalized anxiety | Depression |
| Published | 2006 | 2001 |
| Developers | Spitzer, Kroenke, Williams, Löwe | Spitzer, Kroenke, Williams |
| Items | 7 | 9 |
| Score range | 0–21 | 0–27 |
| Time window | Last 2 weeks | Last 2 weeks |
| Standard cut-point | 10+ | 10+ |
| Severity bands | 0–4 minimal, 5–9 mild, 10–14 moderate, 15–21 severe | 0–4 minimal, 5–9 mild, 10–14 moderate, 15–19 moderately severe, 20–27 severe |
| Asks about self-harm | No | Yes (item 9) |
If you've already taken the GAD-7 and want to understand your number, GAD-7 score interpretation covers every band in detail.
Which One Should You Take?
Start with the pattern you actually notice in yourself.
Lean toward the GAD-7 if your experience sounds like this: your mind won't shut off. You worry about work, health, money, family — and when one worry resolves, another takes its place. You feel keyed up, tense, restless, or irritable. You have trouble relaxing even when nothing is actively wrong. Anxiety points forward: it's your threat system scanning the future for what might go wrong. If that's you, take the free GAD-7 test — it takes about two minutes.
Lean toward the PHQ-9 if your experience sounds like this: things you used to enjoy feel flat. You're exhausted no matter how much you sleep — or you can't sleep at all. Getting through the day feels heavy, your appetite has shifted, and your inner voice has turned harsh. Depression tends to point inward and backward: low mood, low energy, and a critical view of yourself. If that's the closer match, the free PHQ-9 test at our sister site works exactly like this one — nine questions, instant scoring, full interpretation.
Not sure which describes you? That's genuinely common, and it's worth saying: everyday stress can masquerade as either one. If you're mainly reacting to a specific demanding situation — a deadline crunch, a move, a rough season — that may be stress rather than a disorder, and anxiety vs. stress walks through how to tell them apart. But if the symptoms persist regardless of circumstances, screening is the logical next step. And when in doubt, there's a strong case for simply doing both.
Why They're So Often Given Together
Anxiety and depression are the two most common mental health conditions, and they overlap far more than most people expect. Clinicians routinely see patients who meet criteria for both at once, and the conditions feed each other in a well-worn loop: chronic worry is exhausting and demoralizing, which drags mood down; low mood and withdrawal shrink your world, which gives anxiety more room to grow. The two conditions also share real symptom territory — restlessness, irritability, poor sleep, and trouble concentrating can show up in either.
This is exactly why primary care clinics so often staple the two forms together. A patient who walks in describing "stress" might score high on the GAD-7, the PHQ-9, or both — and the treatment conversation looks different in each case. Screening for only one risks catching half the picture.
There's a practical takeaway for you, too: if you score high on one scale, it's worth taking the other. A moderate-or-higher GAD-7 score with a low PHQ-9 suggests anxiety is the primary thread. High scores on both suggest the tangle is bigger than either scale alone can describe — which is useful, concrete information to bring to a doctor or therapist, not a reason for alarm.
What Neither Scale Can Do
The same caution applies to both instruments, and it matters enough to state plainly: these are screening tools, not diagnostic tests. A high score on the GAD-7 doesn't diagnose generalized anxiety disorder, and a high score on the PHQ-9 doesn't diagnose depression. Diagnosis requires a clinician who can weigh your history, rule out medical causes (thyroid issues and certain medications can mimic both conditions), and judge whether your symptoms fit a broader pattern.
Both scales are also snapshots of two weeks. A brutal fortnight can inflate a score; an unusually smooth one can deflate it. If your result surprises you in either direction, retaking the test a couple of weeks later tells you more than any single number can.
And one point that can't wait for a screening score: if you're having thoughts of self-harm or suicide — whether or not you've taken either test — please reach out now. In the US, the 988 Suicide & Crisis Lifeline is available 24/7 by call or text.
The Bottom Line
The GAD-7 and PHQ-9 are two halves of the same toolkit, built by the same research team with the same format and the same two-week lens. The GAD-7 measures the forward-pointing engine of worry and tension; the PHQ-9 measures the inward-pulling weight of low mood and lost interest. Take the one that matches your experience — and if your score comes back elevated, or you honestly can't tell which pattern fits, take both. Together they give you a fuller, evidence-based picture to bring to a professional.
Ready to start with anxiety? Take the free GAD-7 test — seven questions, about two minutes, instant results. And if depression feels like the bigger piece, the free PHQ-9 test is two minutes more.