Table III.

False Positive Rates and Bias Under Null Model Using Linear Mixed Effects Models

	Placebo control phase (ITT)		Active control phase (non-ITT)
	α (%)	Bias	α (%)	Bias
Discontinuation independent of treatment outcomes (MCAR)	5.9	0.0003	4.4	0.002
Discontinuation dependent on observed treatment outcomes (MAR)
Equal dropouts	6.4	0.0005	6.0	0.04
Unequal dropouts
Lack of effectiveness	6.4	0.0006	7.9	−0.39
Toxicity	5.5	0.0003	5.8	0.02

In the placebo control and active control phase, analysis was performed using linear models with random effects and mixed model repeated measures approaches, respectively. In the placebo control phase, all patients are included in the analysis (ITT) while in active control phase patients with data post 48 weeks are only included in the analysis (no imputation for discontinued patients and hence non-ITT)

MCAR missing completely at random, MAR missing at random, ITT intent-to-treat