Table 3

Demographic/clinical variables and self-reported symptoms and their association with hand OA and discriminatory capacity

OR (95% CI)AUC (95% CI)*
Female sex2.42 (1.12–5.20)0.56 (0.48–0.65)
Age, per 5 years1.33 (1.17–1.52)0.70 (0.63–0.78)
Body mass index, per 5 units0.87 (0.64–1.20)0.54 (0.45–0.62)
Family history:

  • OA in first-degree relatives

6.29 (3.15–12.59)0.71 (0.62–0.79)

  • Bony swelling in first-degree relatives

3.53 (1.82–6.85)0.65 (0.57–0.73)
Current or past psoriasis0.45 (0.15–1.29)0.53 (0.44–0.62)
Symptoms in fingers longer than 6 months6.65 (1.34–33.01)0.54 (0.46–0.63)
Duration of morning stiffness, per 15 min:

  • Finger joints

0.97 (0.93–1.00)0.62 (0.53–0.70)

  • Thumb base joints

0.95 (0.89–1.01)0.51 (0.43–0.60)
Hand numbness0.59 (0.33–1.07)0.56 (0.48–0.65)
Number of painful joints on most days the previous 6 weeks:

  • DIP joints

1.22 (1.07–1.40)0.67 (0.59–0.75)

  • PIP joints

0.98 (0.90–1.07)0.52 (0.43–0.61)

  • MCP joints

0.82 (0.73–0.93)0.63 (0.55–0.72)

  • Thumb base joints

1.12 (0.79–1.58)0.53 (0.44–0.61)
Painful joints on most days the previous 6 weeks:

  • Elbow(s)

0.40 (0.20–0.81)0.58 (0.49–0.66)

  • Wrist(s)

0.29 (0.16–0.54)0.64 (0.56–0.72)

  • Toes

0.52 (0.28–0.96)0.57 (0.49–0.66)

  • *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; DIP, distal interphalangeal; MCP, metacarpophalangeal; OA, osteoarthritis; PIP, proximal interphalangeal.