Table 5.

Radiographic and laboratory features and their association with hand OA and discriminatory capacity

OR (95% CI)	AUC (95% CI)*
Number of joints with radiographic osteophytes:
DIP joints	1.62 (1.40–1.88)	0.82 (0.76–0.88)
PIP joints	1.45 (1.27–1.67)	0.78 (0.71–0.85)
MCP joints	1.22 (0.91–1.63)	0.58 (0.49–0.66)
CMC1	2.17 (1.47–3.21)	0.67 (0.59–0.75)
Number of joints with radiographic joint space narrowing:
DIP joints	1.57 (1.36–1.82)	0.82 (0.76–0.89)
PIP joints	1.45 (1.24–1.69)	0.77 (0.70–0.84)
MCP joints	0.98 (0.80–1.20)	0.51 (0.42–0.60)
CMC1	1.94 (1.29–2.91)	0.63 (0.55–0.71)
Number of joints with radiographic central erosions:
DIP joints	2.90 (1.67–5.04)	0.72 (0.65–0.80)
PIP joints	1.52 (1.04–2.21)	0.58 (0.50–0.67)
Number of joints with radiographic marginal erosions:
PIP joints	0.96 (0.57–1.63)	0.53 (0.44–0.61)
MCP joints	0.57 (0.27–1.21)	0.52 (0.43–0.61)
Wrist bones	0.53 (0.29–0.98)	0.56 (0.47–0.65)
Laboratory tests:
Elevated CRP ≥5 mg/L	0.45 (0.24–0.85)	0.59 (0.50–0.67)
Elevated ESR ≥15 mm/hour	0.39 (0.20–0.75)	0.61 (0.52–0.70)
Positive anti-cyclic citrullinated protein	0.13 (0.04–0.50)	0.62 (0.51–0.72)
Positive rheumatoid factor	0.35 (0.14–0.87)	0.59 (0.49–0.70)

*Interpretation of AUC values: 0.50–0.59 = no discrimination, 0.60–0.69 = poor discrimination, 0.70–0.79 = acceptable discrimination, and ≥0.80 = excellent discrimination.

AUC, area under receiver operating curves; CMC1, first carpometacarpal; CRP, Creactive protein; DIP, distal interphalangeal; ESR, erythrocyte sedimentation rate; MCP; metacarpophalangeal; OA, osteoarthritis; PIP, proximal interphalangeal.