# PHQ-9 PHQ-9 Status: LIVE Price: $0.005 USDC `GET /api/calc/phq_9` HTML: https://magentlab.com/docs/phq-9 Markdown: https://magentlab.com/docs/phq-9.md Not a medical device. Not a diagnosis, dose, or listing recommendation. ## What it computes Sum nine caller-assigned Kroenke 2001 PHQ-9 integers (0-3) and return the published total (max 27), severity cutpoints, and ≥10 screen. ## When to use When an agent has already assigned Kroenke 2001 0-3 integers for each of the nine PHQ-9 items and needs the published total, severity cutpoints, and ≥10 screen, not a depression diagnosis or GAD-7. ## When not to use - Not a medical device and not a depression diagnosis or treatment order. - Each of the nine items is a caller-assigned integer 0-3 (0 not at all, 1 several days, 2 more than half the days, 3 nearly every day). magent does not interpret the items. - This is Kroenke 2001 PHQ-9 only (nine DSM-IV depression items; max 27). magent does not score PHQ-2, PHQ-8, or GAD-7. - Published severity cutpoints are 5 / 10 / 15 / 20 (0-4 none_minimal, 5-9 mild, 10-14 moderate, 15-19 moderately_severe, 20-27 severe). Score 0 is none_minimal; magent does not invent a separate none class. screen_ge_10 is true iff score ≥10 (this paper: 88% sensitivity and 88% specificity for major depression). It is a screen, not a diagnosis. ## Formula ``` PHQ-9 = anhedonia + depressed + sleep + energy + appetite + failure + concentration + psychomotor + self_harm; each caller-assigned 0-3; max 27 ``` ## Citation [The PHQ-9: validity of a brief depression severity measure](https://doi.org/10.1046/j.1525-1497.2001.016009606.x) Kroenke K, Spitzer RL, Williams JBW J Gen Intern Med. 2001;16(9):606-613 DOI: [10.1046/j.1525-1497.2001.016009606.x](https://doi.org/10.1046/j.1525-1497.2001.016009606.x) ## Worked example ### All items 0 Given: `anhedonia=0, appetite=0, concentration=0, depressed=0, energy=0, failure=0, psychomotor=0, self_harm=0, sleep=0` 1. anhedonia 0 + depressed 0 + sleep 0 + energy 0 + appetite 0 + failure 0 + concentration 0 + psychomotor 0 + self_harm 0 2. Score = 0 (max 27); severity none_minimal; screen_ge_10 false ### Five items 2 Given: `anhedonia=2, appetite=2, concentration=0, depressed=2, energy=2, failure=0, psychomotor=0, self_harm=0, sleep=2` 1. Score = 10 2. severity moderate; screen_ge_10 true (threshold is ≥10) ## Also searched as - PHQ-9 - PHQ9 - Patient Health Questionnaire-9 - Kroenke PHQ-9 - depression severity measure - nine-item depression questionnaire - PHQ-9 score - DSM-IV PHQ-9 ## Parameters - `anhedonia` (integer, required): Caller-assigned Kroenke 2001 PHQ-9 item 1 (integer 0-3): little interest or pleasure in doing things (0 not at all, 1 several days, 2 more than half the days, 3 nearly every day). magent does not interpret the item. - `depressed` (integer, required): Caller-assigned Kroenke 2001 PHQ-9 item 2 (integer 0-3): feeling down, depressed, or hopeless. magent does not interpret the item. - `sleep` (integer, required): Caller-assigned Kroenke 2001 PHQ-9 item 3 (integer 0-3): trouble falling or staying asleep, or sleeping too much. magent does not interpret the item. - `energy` (integer, required): Caller-assigned Kroenke 2001 PHQ-9 item 4 (integer 0-3): feeling tired or having little energy. magent does not interpret the item. - `appetite` (integer, required): Caller-assigned Kroenke 2001 PHQ-9 item 5 (integer 0-3): poor appetite or overeating. magent does not interpret the item. - `failure` (integer, required): Caller-assigned Kroenke 2001 PHQ-9 item 6 (integer 0-3): feeling bad about yourself — a failure, or having let yourself or your family down. magent does not interpret the item. - `concentration` (integer, required): Caller-assigned Kroenke 2001 PHQ-9 item 7 (integer 0-3): trouble concentrating on things such as reading or watching television. magent does not interpret the item. - `psychomotor` (integer, required): Caller-assigned Kroenke 2001 PHQ-9 item 8 (integer 0-3): moving or speaking so slowly that other people could have noticed, or being so fidgety or restless that you have been moving around a lot more than usual. magent does not interpret the item. - `self_harm` (integer, required): Caller-assigned Kroenke 2001 PHQ-9 item 9 (integer 0-3): thoughts that you would be better off dead, or of hurting yourself in some way. magent does not interpret the item. ## Bulk (POST) POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement. Method: `POST /api/calc/phq_9` Max items: 25 Price: unit_amount + extra_item_amount * (n - 1) (unit 5000 atomic, extra 2000 atomic) Status: PREVIEW - 1 to 25 items. Each item uses the same keys as the GET query parameters. - POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows. - The first invalid item fails the whole request (index in the 400 JSON). You are not charged. - HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row. - Catalog misses (empty matches, found=false) stay paid 200s inside that slot. - x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items. Example request: ```json { "items": [ { "anhedonia": "0", "appetite": "0", "concentration": "0", "depressed": "0", "energy": "0", "failure": "0", "psychomotor": "0", "self_harm": "0", "sleep": "0" }, { "anhedonia": "0", "appetite": "0", "concentration": "0", "depressed": "0", "energy": "0", "failure": "0", "psychomotor": "0", "self_harm": "0", "sleep": "0" } ] } ``` Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/phq-9 Example 200: ```json { "count": 2, "path": "/api/calc/phq_9", "items": [ { "components": [ { "value": 0, "factor": "anhedonia", "points": 0, "present": true }, { "value": 0, "factor": "depressed", "points": 0, "present": true }, { "value": 0, "factor": "sleep", "points": 0, "present": true }, { "value": 0, "factor": "energy", "points": 0, "present": true }, { "value": 0, "factor": "appetite", "points": 0, "present": true }, { "value": 0, "factor": "failure", "points": 0, "present": true }, { "value": 0, "factor": "concentration", "points": 0, "present": true }, { "value": 0, "factor": "psychomotor", "points": 0, "present": true }, { "value": 0, "factor": "self_harm", "points": 0, "present": true } ], "severity": "none_minimal", "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.", "citation": { "authors": "Kroenke K, Spitzer RL, Williams JBW", "doi": "10.1046/j.1525-1497.2001.016009606.x", "id": "kroenke-2001", "pmid": "11556941", "source": "J Gen Intern Med. 2001;16(9):606-613", "title": "The PHQ-9: validity of a brief depression severity measure" }, "formula": "phq_9", "formula_expression": "PHQ-9 = anhedonia + depressed + sleep + energy + appetite + failure + concentration + psychomotor + self_harm; each caller-assigned 0-3; max 27", "max_score": 27, "score": 0, "screen_ge_10": false }, { "components": [ { "value": 0, "factor": "anhedonia", "points": 0, "present": true }, { "value": 0, "factor": "depressed", "points": 0, "present": true }, { "value": 0, "factor": "sleep", "points": 0, "present": true }, { "value": 0, "factor": "energy", "points": 0, "present": true }, { "value": 0, "factor": "appetite", "points": 0, "present": true }, { "value": 0, "factor": "failure", "points": 0, "present": true }, { "value": 0, "factor": "concentration", "points": 0, "present": true }, { "value": 0, "factor": "psychomotor", "points": 0, "present": true }, { "value": 0, "factor": "self_harm", "points": 0, "present": true } ], "severity": "none_minimal", "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.", "citation": { "authors": "Kroenke K, Spitzer RL, Williams JBW", "doi": "10.1046/j.1525-1497.2001.016009606.x", "id": "kroenke-2001", "pmid": "11556941", "source": "J Gen Intern Med. 2001;16(9):606-613", "title": "The PHQ-9: validity of a brief depression severity measure" }, "formula": "phq_9", "formula_expression": "PHQ-9 = anhedonia + depressed + sleep + energy + appetite + failure + concentration + psychomotor + self_harm; each caller-assigned 0-3; max 27", "max_score": 27, "score": 0, "screen_ge_10": false } ] } ``` ## Response fields - `formula` (string): phq_9 - `formula_expression` (string): Exact expression used - `score` (integer): PHQ-9 points 0-27 - `max_score` (integer): 27 - `severity` (string): Kroenke 2001 cutpoints: none_minimal (0-4), mild (5-9), moderate (10-14), moderately_severe (15-19), severe (20-27). Score 0 is none_minimal. Not a diagnosis. - `screen_ge_10` (boolean): true iff score ≥ 10 (Kroenke 2001: score ≥10 sensitivity 88% and specificity 88% for major depression). Not a diagnosis. - `components` (array): Per-item caller-assigned points - `citation` (object): Kroenke et al. J Gen Intern Med 2001 citation - `disclaimer` (string): Not-a-device notice ## Example JSON Frozen fixture. Not a live lookup. ```json { "components": [ { "value": 0, "factor": "anhedonia", "points": 0, "present": true }, { "value": 0, "factor": "depressed", "points": 0, "present": true }, { "value": 0, "factor": "sleep", "points": 0, "present": true }, { "value": 0, "factor": "energy", "points": 0, "present": true }, { "value": 0, "factor": "appetite", "points": 0, "present": true }, { "value": 0, "factor": "failure", "points": 0, "present": true }, { "value": 0, "factor": "concentration", "points": 0, "present": true }, { "value": 0, "factor": "psychomotor", "points": 0, "present": true }, { "value": 0, "factor": "self_harm", "points": 0, "present": true } ], "severity": "none_minimal", "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.", "citation": { "authors": "Kroenke K, Spitzer RL, Williams JBW", "doi": "10.1046/j.1525-1497.2001.016009606.x", "id": "kroenke-2001", "pmid": "11556941", "source": "J Gen Intern Med. 2001;16(9):606-613", "title": "The PHQ-9: validity of a brief depression severity measure" }, "formula": "phq_9", "formula_expression": "PHQ-9 = anhedonia + depressed + sleep + energy + appetite + failure + concentration + psychomotor + self_harm; each caller-assigned 0-3; max 27", "max_score": 27, "score": 0, "screen_ge_10": false } ``` ## Errors - HTTP 400 `invalid_phq9_item`: each PHQ-9 item must be an integer from 0 to 3 (Kroenke 2001: 0 not at all, 1 several days, 2 more than half the days, 3 nearly every day). Returned before settlement; you are not charged. - HTTP 400 `invalid_items`: POST body must be a JSON object with only an items array Returned before settlement; you are not charged. - HTTP 400 `invalid_item_count`: items must be an array of 1 to 25 objects Returned before settlement; you are not charged. - HTTP 400 `invalid_item`: each items entry must be a JSON object Returned before settlement; you are not charged. Shared HTTP 402 and 503: https://magentlab.com/docs/payments ## Related tools - [GAD-7](https://magentlab.com/docs/gad-7) — Sum seven caller-assigned Spitzer 2006 GAD-7 integers (0-3) and return the published 0-21 total, 5/10/15 severity cuts, and ≥10 case-finding flag. - [CAGE](https://magentlab.com/docs/cage) — Sum the four Ewing 1984 CAGE items and return whether two or more answers are affirmative. - [AUDIT-C](https://magentlab.com/docs/audit-c) — Sum three caller-assigned Bush 1998 AUDIT-C integers (0-4) and return this paper's ≥3 and ≥4 screens. ## Payment Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s. - GET the tool with Accept: application/json (do not send Accept: text/html unless you want the human paywall). - HTTP 402 means you have not paid. Decode the base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote. - Sign accepts[0] (exact, EIP-3009) with validBefore = now + maxTimeoutSeconds (600 seconds), or accepts[1] (batch-settlement deposit/voucher) on product GET. Ping and POST {items} stay exact. Magent retries transient facilitator 429/5xx before answering. - Retry the same URL with PAYMENT-SIGNATURE (base64 JSON of accepted and payload). Magent attaches canonical extensions.bazaar on CDP verify/settle; echoing 402 bazaar is optional. - Success is HTTP 200 JSON plus PAYMENT-RESPONSE. exact settles before the tool. batch-settlement verifies (and deposit-settles) before the tool and commits the charge after HTTP 2xx. HTTP 503: retry the same PAYMENT-SIGNATURE. Mint a new exact nonce only after a new HTTP 402. - offered `exact` on eip155:8453: Fixed-price USDC on Base. The buyer authorizes the advertised amount (EIP-3009). magent settles before the tool runs (paymentFlow upfront). extra.assetTransferMethod=eip3009 extra.paymentFlow=upfront. - offered `batch-settlement` on eip155:8453: Payment-channel vouchers claimed later in batches. Exact stays accepts[0]. Same-path POST {items} is still exact. extra.assetTransferMethod=eip3009 extra.paymentFlow=authorization. - not offered `upto`: Not offered. Usage-based: buyer authorizes a ceiling, seller settles the actual amount after work. Reserved for a future metered tool. Not for current calculators or code search. Same-path POST {items} is still scheme exact: one EIP-3009 authorization for GET unit plus $0.002 per extra item. That is not x402 batch-settlement (payment channels / vouchers). Shared HTTP 402 and 503 table: https://magentlab.com/docs/payments Stdio MCP (one process per host): https://magentlab.com/docs/mcp ## Guarantees - HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. - exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE. - HTTP 402 is unpaid only. Do not sign a second authorization because of a 503. - Execution is timeout-bounded and concurrency-capped. - Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.