Table 4 Summary of quality assessment of included studies with before-and-after design (n = 2)

Sampling

1. Was probability sampling used?

2. Was sample size justified to obtain appropriate power?

3. Are the participants in the study likely to be representative of the target population?

   a. Very likely

   b. Somewhat likely

   c. Not likely

Design

1. One pretest or baseline and several posttest measures

2. Simple before-and-after study

Control of confounders:

1. Does the comparison strategy attempt to create or assess equivalence of the groups at baseline?

   a. Yes, by matching

   b. Yes, by statistical adjustment

   c. No

2. The group comparisons were the same for all occasions: (pre, baseline, and post evaluation)

Data collection and outcome measurement

1. Reliability indices

Statistical analysis

1. Was (were) the statistical test(s) used appropriate for the aim of the study?

2. Were p-values reported?

3. Were confidence intervals reported?

4. Were missing data managed appropriately?

Drop outs

Is attrition rate < 30%?