Table 2.

Fixed-effect Model for Predictors of Change in Sputum Iron from Baseline

Effect*	Estimate	S.E.	t-value	p-value
Intercept	−3.418	1.854	−1.84	0.08
Drug sequence	0.236	0.248	0.95	0.35
Period	−0.126	0.181	−0.70	0.49
Ferrous sulfate	−0.281	0.196	−1.43	0.16
Antibiotic use	0.054	0.228	0.24	0.81
FEV1 (% predicted)	−0.017	0.013	−1.30	0.20
Serum iron (µg/dl)*	0.410	0.251	1.64	0.11
Serum hepcidin-25 (ng/ml)	0.011	0.004	2.51	0.02
Akron PES	−0.032	0.041	−0.77	0.45
Serum EPO (mU/ml)	0.052	0.020	2.66	0.01
Hemoglobin (gm/dl)	0.082	0.142	0.58	0.57
Body weight (kg)	−0.014	0.063	−0.22	0.83

S.E. = standard error

^*Log-transformed prior to introduction into model.