Table 6.
Risk of bias assessment.
| Author and year | Randomization | Allocation concealment | Blinding | Standardized preparation | Reporting data |
|---|---|---|---|---|---|
| Ok et al. 2015 [5] | Unclear (teeth were randomly divided) | High (not mentioned) | High (not mentioned) | Low | Low |
| Pujar et al. 2011 [11] | Unclear (the samples were divided.) | High (not mentioned) | High (not mentioned) | High (strain not mentioned, irrigation protocol not mentioned, also the type of needle used) | Low |
| Choudhary et al. 2018 [12] | Low | High (not mentioned) | High (not mentioned) | Low | Low |
| Sedigh-Shams et al. 2015 [13] | High (not mentioned) | High (not mentioned) | High (not mentioned) | Low | Low |
| Rosaline et al. 2013 [14] | Unclear (teeth were randomly divided) | High (not mentioned) | High (not mentioned) | High (canal preparation not mentioned, the volume of irrigant used not mentioned, and the type of needle used not mentioned) | Low |
| Gupta-Wadhwa et al. 2016 [15] | Unclear (samples were randomly divided) | High (not mentioned) | High (not mentioned) | Low | Low |
| Sharifian et al. 2009 [16] | Unclear (samples were randomly divided) | High (not mentioned) | High (not mentioned) | High (irrigation protocol not mentioned, the volume of irrigant and type of needle used not mentioned) | Low |
| Divia et al. 2018 [17] | High (not mentioned) | High (not mentioned) | High (not mentioned) | High (irrigation protocol not mentioned, the volume of irrigant, time of irrigation, type of needle used, sample collection, and culture medium were not mentioned) | High |
| Kumar et al. 2018 [18] | High | High (not mentioned) | High (not mentioned) | Unclear (irrigation protocol not mentioned) | Low |