Table 1.

Kmet et al. (2004) quality ratings for the quantitative studies

Study	Cassado et al.	Giunta et al.	Lai and Surood	Li	Townsend and Kosloski
Question/objective sufficiently described	2	2	2	2	2
Study design evident and appropriate	2	2	2	2	2
Method of subject/comparison group selection or source of information/input variables described and appropriate	2	2	2	2	2
Subject characteristics sufficiently described	1	2	2	1	2
If intervention and random allocation were possible, were they described	N/A	N/A	N/A	N/A	N/A
If intervention and blinding of investigators were possible, were they reported	N/A	N/A	N/A	N/A	N/A
If intervention and blinding of subjects were possible, were they reported	N/A	N/A	N/A	N/A	N/A
Outcome and (if applicable) exposure measures well defined and robust to measurement	1	1	2	2	1
Sample size appropriate	2	2	2	2	2
Analytical methods described/justified/appropriate	2	2	2	2	2
Estimate of variance is reported for the main results	2	2	2	1	2
Controlled for confounding	1	2	2	2	1
Results reported in sufficient detail	2	2	2	2	2
Conclusions supported by the results	2	2	2	2	2
Total score	19/22	21/22	22/22	20/22	20/22

Yes = 2, Partial = 1, No = 0 or not applicable (N/A). Total maximum possible scores therefore can vary.