Table 1 Criteria used to assess the quality of studies
Quality item | No. of studies | Percentage (%) |
|---|---|---|
Specification of the target population | 24 | 100 |
Use of adequate sampling techniques | 24 | 100 |
Adequate sample size (> 300 participants) | 20 | 83 |
Adequate response rate (≥ 80) | 24 | 100 |
Measurement with valid and tested instruments | 9 | 38 |
Reported confidence intervals or standard errors | 10 | 42 |
Reported attempt to reduce bias | 24 | 100 |
Study subject described in detail | 23 | 96 |