Table 4.

Quality assessment for the quantitative studies included in this review

Studies	Inclusion criteria are varied for each group	Recruitment strategy are varied for each group	Inappropriate comparator group	Valid measures implemented?	Attempt to balance the allocation?	Taking cofounders into account?
Ben Romdhane 2014	N/A	N/A	N/A, study with no comparator group	No, used information from self-reported	N/A	Yes, in the analysis
Sosa-Rubi 2009	No, initially derived data from census	No, original census recruited sample with the same strategy	No, health insurance status is voluntary	No, used information from self-reported	Yes, used standard propensity score matching	Yes, in the analysis
Stephens 2013	N/A	N/A	N/A, study with no comparator group	Yes, IMS prescribing data	N/A	Yes, with age
Cunningham-Myrie 2013	No, initially derived data from health survey	No, original survey recruited sample with the same strategy	No, controls were in accordance with study aim	Cannot determine, reported ‘only current use of pharmacological drugs, was considered as being on therapy’, but didn’t provide detail on how to determine current use	Yes, applied survey weight	Yes, in the analysis
Baumann 2010	N/A	N/A	N/A, study with no comparator group	No, used information from self-reported	N/A	Cannot determine (descriptive results)
Le 2011	N/A	N/A	N/A, study with no comparator group	No, used information from self-reported	N/A	Yes, in the analysis
Gakidoue 2011	N/A	N/A	N/A, study with no comparator group	Cannot determine as measurement approach not reported	N/A	Cannot determine (data were derived from other studies)

N/A, not applicable.