Table 3.
Methodological assessment using specific criteria described in the AHRQ to assess the risk of bias for benefits for cross-sectional studies.
| Studies | ltems | Quality | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | Score | ||
| Balci et al. (1999) [28] | + | + | + | − | − | + | + | − | + | 6/9 | C |
| Bridgman et al. (1972) [43] | + | − | + | − | − | + | + | − | + | 5/9 | C |
| Cole et al. (2009) [8] | + | + | + | + | − | + | + | + | + | 8/9 | C |
| Czelusniak et al. (2012) [29] | + | − | + | + | − | + | + | − | + | 6/9 | C |
| Escalente et al. (1999) [44] | − | + | + | − | − | − | + | + | + | 5/9 | C |
| Lee et al. (2015) [32] | + | + | + | + | − | + | + | + | + | 8/9 | C |
| Ramchurn et al. (2009) [35] | − | + | − | + | + | + | + | − | + | 6/9 | C |
| Schulte et al. (1993) [37] | + | + | + | + | − | + | + | + | + | 8/9 | C |
| Withrington et al. (1985) [45] | − | − | − | − | − | + | − | − | + | 2/9 | C |
| Yian et al. (2012) [46] | + | + | + | + | − | + | + | + | + | 8/9 | C |
| Selection bias 1: Did the study apply inclusion/exclusion criteria uniformly to all comparison groups? 2: Does the design or analysis control account for important confounding and modifying variables through matching, stratification, multivariable analysis, or other approaches? | |||||||||||
| Performance bias 3: Did researchers rule out any impact from a concurrent intervention or an unintended exposure that might bias results? | |||||||||||
| Attrition bias 4: If attrition (overall or differential non response, dropout, loss to follow-up, or exclusion of participants) was a concern, were missing data handled appropriately (e.g., intention-to-treat analysis and imputation)? | |||||||||||
| Detection of bias 5: Were the outcome assessors blinded to the intervention or exposure status of participants? 6: Were interventions/exposures assessed/defined using valid and reliable measures, implemented consistently across all study participants? 7: Were outcomes assessed/defined using valid and reliable measures, implemented consistently across all study participants? 8: Were confounding variables assessed using valid and reliable measures, implemented consistently across all study participants? | |||||||||||
| Reporting bias 9: Were the potential outcomes prespecified by the researchers? Are all prespecified outcomes reported? | |||||||||||