nbmecalc-score-conversion

nbmecalc-score-conversion

Small, dependency-free JavaScript helpers for interpreting NBME-style practice-assessment inputs during USMLE study planning.

This package supports NBME, UWSA 1/2, Free 120, AMBOSS, and CMS inputs for Step 1, Step 2 CK, and Step 3 workflows. It returns an internally equated three-digit planning value and a model-generated interval so downstream tools can show uncertainty instead of a falsely precise single number.

The mappings are independent assumptions. They are not official NBME or USMLE conversions, do not represent NBME endorsement, and have not been evaluated in a published independent holdout cohort. Read the NBME score conversion page for the browser workflow and the public methodology and assumptions before using the output.

Install

npm install nbmecalc-score-conversion

Use

import { computeEstimate, convertExam } from "nbmecalc-score-conversion";

const single = convertExam({ source: "NBME", score: 240, formNumber: 32 }, "step2");
console.log(single); // 249 under algorithm v1.1 assumptions

const estimate = computeEstimate([
  { source: "NBME", score: 240, formNumber: 32, takenDaysAgo: 2 },
  { source: "FREE120", score: 75, takenDaysAgo: 8 },
], "step2");

console.log(estimate.pointEstimate, estimate.ciLower, estimate.ciUpper);

source is one of NBME, UWSA1, UWSA2, FREE120, AMBOSS, or CMS. Percent-correct inputs are represented by their numeric percentage; three-digit inputs are represented by their reported score. CMS inputs below 150 are treated as percent-correct subject signals, while values at or above 150 are treated as already-equated inputs.

The package deliberately performs local deterministic calculations and makes no network requests. It is intended for educational planning and software integration, not eligibility, clinical, licensing, or institutional decisions.

Related NBMEcalc resources

• Free NBME Score Calculator
• CMS Form Score Interpretation Guide
• NBMEcalc validation status

Development

npm test
npm run build
npm run pack:check

Source repository: github.com/jiankn/nbmecalc