Characteristics | PP+ (n = 45) | PP- (n = 96) | CO (n = 55) | PP+ versus PP- | PP+ versus CO |
---|---|---|---|---|---|
Female (%) | 76 | 65 | 58 | ||
Mean age (years) | 4.7 | 8.2 | 8.6 | P < 0.01a | P < 0.01a |
Laboratory findings | |||||
Haemoglobin level <11.8 g/dl (%) | 61 | 34 | 24 | P < 0.01b | P < 0.01b |
Mean white blood cell count (cells/μl) | 10,440 | 8,000 | 8,110 | P < 0.01a | P < 0.01a |
Mean platelet count (×10e3/μl) | 409 | 362 | 332 | P < 0.01a | |
ESR >11 mm/hour (%) | 71 | 51 | 30 | P < 0.01c | P < 0.01c |
Positivity for ANAs (%) | 51 | 45 | 24 | P < 0.05b | |
Factors relating to the skin | |||||
SPT I and II (%) | 58 | 39 | 53 | P < 0.05b | |
Freckles (%) | 42 | 34 | 36 | ||
Blue/grey eye colour (%) | 68 | 72 | 60 | ||
Fair hair colour (%) | 61 | 50 | 51 | ||
Regular skin care (%) | 82 | 75 | 82 | ||
Intense sun exposure during vacation (%) | 47 | 31 | 25 | P < 0.05b | |
Photoprotective measures (%) | 89 | 83 | 85 | ||
Application of sun screen with >20 SPF (%) | 44 | 50 | 42 | ||
Atopic diathesis (%) | 21 | 25 | 16 | ||
Psoriasis (%) | 8 | 3 | 2 | ||
Factors relating to naproxen therapy and comedication | |||||
Mean duration of naproxen therapy (months) | 22.8 | 20.2 | - | ||
Mean dosage of naproxen (mg/kg per day) | 16.7 | 15.5 | - | ||
Maximal mean dosage of naproxen (mg/kg per day) | 17.6 | 16.7 | - | ||
Increased naproxen dosage during the course of treatment (%) | 42 | 24 | - | P < 0.05b | |
Comedication (%) | 58 | 38 | - | P < 0.05b | |
Chloroquine as comedication (%) | 27 | 6 | - | P < 0.01b |