Table 2.
Study quality and risk of bias assessment of included studies on oral probiotic intake according to the Cochrane Collaboration’s tool.
| Study (year) | Random sequence generation | Allocation concealment | Blinding of participants and personnel | Blinding of outcome assessment | Incomplete outcome data | Selective outcome reporting | Other sources of bias | Overall quality* |
|---|---|---|---|---|---|---|---|---|
| Harbige et al. (2016) | U | U | U | U | L | L | H | Poor |
| Childs et al. (2014) | L | L | L | L | L | L | U | Good |
| Rizzardini et al. (2012) | L | L | L | U | L | L | L | Good |
| Cox et al. (2008) | U | L | L | U | L | L | L | Fair |
| Kekkonen et al. (2008) | U | U | U | U | L | L | L | Poor |
U; unclear risk of bias, L; low risk of bias, H; high risk of bias.
*Good quality: all criteria met; Fair quality: one criterion not met (i.e. high risk of bias for one domain or two criteria unclear); Poor quality: two or more criteria listed as high or unclear risk of bias.