Table 1

Baseline characteristics of IMPROVED study population

Total population
n=610
DAS, mean±SD3.2±0.91
HAQ, mean±SD1.2±0.66
Age (years), mean±SD52±14
Female, n (%)414 (68)
Symptom duration (weeks), median (IQR)18 (9.0–32)
RF positive, n (%)339 (56)
ACPA positive, n (%)333 (55)
Anti-CarP positive, n (%)172 (28)
Fulfilled RA 2010 classification criteria, n (%)479 (79)
Swollen joint count, median (IQR)/mean±SD5.0 (3.0–10)/7.3±6.2
Tender joint count, median (IQR)/mean±SD6.0 (4.0–9.0)/7.5±5.0
ESR (mm/hour), median (IQR)25 (11–39)
VAS global health (mm), mean±SD46±23
Total SHS, median (IQR)/mean±SD (observed)0.0 (0.0–3.0)/2.1±4.2
Total SHS, median (IQR)/mean±SD (after imputation)0.49 (0.0–3.0)/2.1±4.2
Erosive, n (%) (observed)73 (12)
Erosive, n (%) (after imputation)79 (13)
  • Erosive indicates ≥1 erosions.

  • ACPA, anticitrullinated protein antibody; anti-CarP, anticarbamylated protein antibodies; DAS, Disease Activity Score; ESR, erythrocyte sedimentation rate; HAQ, Health Assessment Questionnaire; IMPROVED, Induction therapy with MTX and Prednisone in Rheumatoid Or Very Early arthritic Disease; RA, rheumatoid arthritis; RF, rheumatoid factor; SHS, Sharp/van der Heijde Score; VAS, Visual Analogue Scale.