Table 2.

Hierarchical regression models to assess predictors of sleep problems index

Variables	β Coeff.	P-value	Adj. R2
Model 1
Age, years	0.04	0.74	0.0186
Sex	7.2	0.087
Non-white	0.81	0.819
BMI	0.57	0.031
Model 2
Age, years	0.05	0.62	0.1432
Sex	9.43	0.03
Non-white	−1.74	0.63
BMI	0.49	0.07
MRSS	−0.13	0.50
Physician global severity	3.48	<0.001
Model 3A—Total GIT score modela
Age, years	−0.01	0.87	0.4221
Sex	7.60	0.04
Non-white	−2.67	0.39
BMI	0.21	0.38
MRSS	0.05	0.76
Physician global severity	0.96	0.18
Worsening of GI symptoms during last month	−6.59	0.04
Worsening of shortness of breath during past 1 month	8.10	0.01
FACIT-Fatigue	−0.28	0.072
CESD	1.31	<0.001
Swollen joint count	−3.12	0.09
Total GIT score	6.29	0.074
Model 3B—GI scales modela
Age, years	−0.04	0.708	0.4236
Sex	7.83	0.03
Non-white	−2.29	0.48
BMI	0.21	0.40
MRSS	−0.03	0.84
Physician global severity	0.78	0.30
Worsening of GI symptoms during last month	−5.77	0.07
Worsening of shortness of breath during past 1 month	5.33	0.12
FACIT-Fatigue	−0.29	0.05
CESD	1.07	0.001
Swollen joint count	−3.40	0.07
Reflux scale of UCLA SCTC GIT 2.0	8.02	0.009

^aStepwise regression model.