Table 2.

Correlation between serum IFN activity; levels of IFN-α, IFN-γ and IFN-λ1; disease activity and damage

Parameter	IFN activity (ρ)	p value	IFN-γ (ρ)	p value
IFN-α	0.25	< 0.0001	0.2	0.009
IFN-γ	0.4	< 0.0001	–	–
IFN-λ1	0.12	0.04	0.05	ns
SLAM	0.3	< 0.0001	0.08	ns
SLEDAI	0.3	< 0.0001	0.14	0.005
SDI	− 0.13	0.003	− 0.02	ns
Prednisone dose	0.07	ns	− 0.06	ns

Statistical analysis was performed by Spearman rank correlation test. Results are presented as Spearman rank correlation coefficient (ρ)

SLAM Systemic Lupus Activity Measure, SLEDAI SLE Disease Activity Index, SDI SLE disease damage index