Criteria of RA (5-1-1)
5-Arthritis
1-SubQ
1-Serological

Arthritis
1. Morning stiffness: > 1hr
2. Arthritis: > 3 in 14
---bil elbow, wrist, MCP, PIP
---bil knee, ankle, MTP
3. hand arthritis: wrist, MCP, PIP
4. symmetric:
5. X-Ray: bony erosion, unequivocal decalcification

SubQ
---Rheumatoid nodule over bony prominence

Serological
---Rheumatoid factor (>20)