Table 3.

Bias Evaluation for Randomized Trials (n =)

Reference	Random Sequence Generation (Selection Bias)	Allocation Concealment (Selection Bias)	Blinding of Participants and Personnel (Performance Bias)	Blinding of Outcome Assessment (Detection Bias)	Incomplete Outcome Data (Attrition Bias)	Selective Reporting (Reporting Bias)	Other Bias	Comments
Dewar et al. 2014	U	H	U	H				No details on randomization procedures
Haug et al. 2013a			H
Huang, Dillon 2014	U	U	H	U	L	L	H	Tailored TM & phone counseling not described; effect of mobile component unknown
Huang Terrones 2014	L	L	H	L	L	L	H	Tailored TM & phone counseling not described; effect of mobile component unknown
Lana et al. 2013	U	U	H	U	H	L	L	No details on randomization procedures
Love-Osborne et al.	H	H	H	H	L	L	H	No details on randomization procedures; authors noted several confounders in both groups
Nguyen et al.	U	U	U	H	H	L	H	No details on randomization procedures; no true control group
Seid et al.	H	H	L	L	L	L	U
Shi et al.	U	U	U	U	H	L	H	Potential recruitment bias with cluster randomization
Skov-Ettrup et al.	U	U	L	U	H	L	H	>60% attrition in both intervention groups; design does not allow conclusion of whether effect caused by tailoring or TM frequency

Legend: H = high risk of bias; L = low risk of bias; U = unclear bias; TM = text messaging