Effect Size 2x2

{
  "asOf": "2026-10-11T08:55:55.525Z",
  "confidence": 0.95,
  "correctionApplied": false,
  "degraded": false,
  "direction": "NNH (harm) if the event is bad",
  "disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
  "notChecked": [
    "confounding and bias: these measure association in these data, not cause",
    "study design (case-control studies cannot estimate relative risk directly)",
    "…1 more"
  ],
  "numberNeededToTreat": 10,
  "oddsRatio": 2.25,
  "oddsRatioCI": {
    "lower": 0.994295,
    "upper": 5.09155
  },
  "reasons": [
    "The interval includes 1: the data are consistent with no association.",
    "When the outcome is common (over about 10%) the odds ratio overstates the relative risk.",
    "…1 more"
  ],
  "relativeRisk": 2,
  "relativeRiskCI": {
    "lower": 0.986563,
    "upper": 4.05448
  },
  "riskDifference": 0.1,
  "riskDifferenceCI": {
    "lower": 0.0020018008,
    "upper": 0.1979982
  },
  "riskExposed": 0.2,
  "riskUnexposed": 0.1,
  "source": "computed locally",
  "summary": "Risk 20% vs 10%: odds ratio 2.25 (95% CI 0.994295 to 5.09155), relative risk 2 (0.986563 to 4.05448), risk difference 10 points, NNT 10.",
  "verdict": "INTERVAL_INCLUDES_NO_EFFECT"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://stats-tests.x402tookit.com/effect-size-2x2?exposedEvents=20&exposedNoEvents=80&unexposedEvents=10&unexposedNoEvents=90'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - 'https://stats-tests.x402tookit.com/effect-size-2x2?exposedEvents=20&exposedNoEvents=80&unexposedEvents=10&unexposedNoEvents=90' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode

// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

// Pays at most $0.02 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.02" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.02 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fstats-tests.x402tookit.com%2Feffect-size-2x2
const res = await pay("https://stats-tests.x402tookit.com/effect-size-2x2?exposedEvents=20&exposedNoEvents=80&unexposedEvents=10&unexposedNoEvents=90");
console.log(res.status, await res.text());

# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.02 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.02"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://stats-tests.x402tookit.com/effect-size-2x2?exposedEvents=20&exposedNoEvents=80&unexposedEvents=10&unexposedNoEvents=90")
    print(res.status_code, res.text)