Psychometric properties of FACIT-Fatigue in systemic lupus erythematosus: a pooled analysis of three phase 3 randomised, double-blind, parallel-group controlled studies (BLISS-SC, BLISS-52, BLISS-76)

Journal of Patient-Reported Outcomes

Table 6 Mean change from baseline in FACIT-Fatigue scores by improvement in PGA and BILAG response rate (pooled sample)

Week		Mean change	[95% CI]	Δ^a	95% CI	p-value
PGA improvement
Week 24	No (n = 972)	2.1	[1.4, 2.7]	−3.9	[−4.7, −3.0]	< 0.0001
Week 24	Yes (n = 1496)	5.9	[5.4, 6.4]	−3.9	[−4.7, −3.0]	< 0.0001
Week 52	No (n = 861)	1.9	[1.1, 2.8]	−4.0	[−5.0, −3.0]	< 0.0001
Week 52	Yes (n = 1481)	5.9	[5.4, 6.4]	−4.0	[−5.0, −3.0]	< 0.0001
BILAG response ≥ 50%^b
Week 24	No (n = 835)	2.7	[2.0, 3.4]	−2.7	[−3.6, −1.9]	< 0.0001
Week 24	Yes (n = 1611)	5.4	[4.9, 5.9]	−2.7	[−3.6, −1.9]	< 0.0001
Week 52	No (n = 838)	3.3	[2.5, 4.1]	−2.2	[−3.1, −1.2]	< 0.0001
Week 52	Yes (n = 1528)	5.5	[4.9, 6.0]	−2.2	[−3.1, −1.2]	< 0.0001

^aΔ (difference) calculated as (improvement in PGA – no improvement in PGA) or (BILAG responder < 50% – BILAG responder ≥50%). Analyses to evaluate ability to detect change used data from baseline through Week 24 and from baseline to Week 52 to calculate BILAG response at Week 24 and Week 52, respectively
^bBased on a total of 7 and 14 assessments per patient between baseline and Weeks 24 and 52, respectively
BILAG British Isles Lupus Assessment Group, CI confidence interval, FACIT Functional Assessment of Chronic Illness Therapy, PGA Physician’s Global Assessment, W Week