Quantitative non-randomized studies

Quality assessment components using MMAT

Are participants recruited in a way that minimizes selection bias?

Are measurements appropriate regarding the exposure or intervention and outcomes?

In the groups being compared, are the participants comparable, or do researchers consider?

Are there complete outcome data (80% or above), an acceptable response rate (60% or above), or an acceptable follow-up rate for cohort studies?

Total

Al-Ghamdi et al., [2017]

*

*

*

*

4*

Allaire et al., [2000]

*

*

*

*

4*

Bercaw et al., [2010]

*

*

*

3*

Charaf et al., [2015]

*

*

*

*

4*

Chaudhry et al., [2011]

*

*

*

*

4*

Fakeye et al., [2009]

*

*

*

3*

Holst et al., [2009]

*

*

*

*

4*

Hwang et al., [2016]

*

*

*

*

4*

Kaadaga et al., [2014]

*

*

*

*

4*

Kenedy et al., [2013]

*

*

*

*

4*

Louik et al., [2010]

*

*

*

*

4*

Mothupi et al., [2014]

*

*

*

*

4*

Moussally et al., [2009]

*

*

*

*

4*

Nordeng et al., [2011]

*

*

*

*

4*

Nordeng et al., [2004]

*

*

*

*

4*