ACR Criteria Calculator

ACR Criteria Calculator for Rheumatology. Six or more meets the classification threshold only when eligibility is satisfied. A lower total does not prove absence of RA. The form produces no result when synovitis or exclusion of a better alternative has not been confirmed.

For shared guidance on choosing a tool and documenting results, read the clinical calculator workflow.

How this calculator works

These are the 2010 ACR/EULAR RA classification criteria, not every ACR criteria set. In an eligible patient, add one category from each of four domains. The joint domain contributes up to five, serology three, acute-phase response one and duration one.

When to use this calculator

First establish clinical synovitis in at least one eligible joint and exclude a better explanation. The scoring population is not people with isolated positive antibodies or nonspecific arthralgia. Reassess evolving presentations rather than treating one score as permanent.

Inputs used

  • Eligibility assessment for clinical synovitis and alternatives, highest joint category, RF/ACPA relative to assay ULN, acute-phase findings and symptom duration.

Clinical interpretation

Six or more meets the classification threshold only when eligibility is satisfied. A lower total does not prove absence of RA. The form produces no result when synovitis or exclusion of a better alternative has not been confirmed.

Worked example

Four involved small joints contribute three, low-positive serology two, abnormal CRP one and symptoms lasting five weeks zero: total six. Exactly six weeks adds one. A result exactly three times ULN is low-positive, not high-positive.

Limitations and safety notes

Exclude DIP, first CMC and first MTP joints from the joint domain. Qualitative positive RF is low-positive. At least one serological and one acute-phase result are required; missing tests are not normal. The page does not implement retrospective erosive-disease pathways.

References

  • https://ard.bmj.com/content/69/9/1580

Editorial review and citation methodology

Maintained by the Quick Medical Calculator Editorial Team. Content record date: September 9, 2026. A content date is not evidence of independent clinical review. Individual clinical sign-off is not recorded on this page.

  • Prefer original validation studies for scoring systems and prediction tools.
  • Use current specialty society guidance, transplant allocation policy, public health guidance, or regulator resources when they govern clinical use.
  • Include limitations and safety notes when a calculator is population-specific, context-dependent, or unsuitable as a standalone decision tool.

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