Table 1

Characteristics of participants in the analysis stratified by variables with complete or incomplete data (n=126 534)

Seropositive RASeronegative RAControls
ObservedImputedAllObservedImputedAllObservedImputedAll
Complete datan=7887n=0n=3398n=0n=115 249n=0
Age (median)596260
Women (%)706368
Exposed to asbestos (%)564
Exposed to silica (%)775
Incomplete data
Educationn=7876n=11n=7887n=3391n=7n=3398n=114 992n=257n=115 249
 ≤9 years (%)315531303630273627
 10–12 years (%)463346454445454345
 >12 years (%)241124242124282128
Smokingn=2026n=5861n=7887n=659n=2739n=3398n=4356n=110 893n=115 249
 Ever smoking (%)727070575757555756
 Pack-years (median)181919151414131414
Alcohol consumptionn=2168n=5719n=7887n=716n=2682n= 398n=4700n=110 549n=115 249
 Non-drinkers (%)1078978677
 Low consumption (%)545454515151474646
 Moderate consumption (%)212222232323242424
 High consumption (%)151717171918232222
  • RA, rheumatoid arthritis;.