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Table 1 Participant characteristic table

From: Exploring differential item functioning in the SF-36 by demographic, clinical, psychological and social factors in an osteoarthritis population

Gender (male, %, (n)) 43.3% (330)
Age (Mean years, s.d.) 69.5 (10.0)
Marital status (married, %, (n)) 72% (543)
Ethnicity (white, &, (n)) 99.1% (750)
Paid employment (yes, %, (n)) 33.7% (247)
Social class (%, (n))  
  I 5.7% (43)
  II 33.8% (256)
  IIINM 19.0% (144)
  III M 23.4% (177)
  IV 14.7% (111)
  V 3.4% (26)
Townsend quintiles (lower = most affluent)  
  20% -2.7
  40% -1.9
  60% -0.80
  80% 1.4
Mood (mod or severe/none; %, (n)) 30%/70% (218/534)
BMI (mean(s.d.)) 29.2 (5.3)
Affected joints (n)  
  Hip OA 487
  Knee OA 612
  Both hip and Knee OA 336
  Hip OA only 151
  Knee OA only 276
 No of affected hip/knee joints (1/2v3/4;%, (n)) 57%/43% (218/435)
SF-36 subscales^  
 Physical functioning (mean(s.d.) 50.0% (29.0)
 Pain (mean(s.d.) 42.3% (20.0)
 Role physical (mean(s.d.) 39.2% (41.7)
 Social (mean(s.d.) 71.8% (28.3)
 Role emotional (mean(s.d.) 57.7% (42.9)
 Mental health (mean(s.d.) 73.9% (18.1)
 Vitality (mean(s.d.) 50.8% (21.3)
 General health (mean(s.d.) 59.6% (21.2)
  1. ^ higher = better function.