TABLE 2.
The risk-of-bias assessment of the included studies assessing the effect of nutritional biomarkers on biological aging in older adults, using the ROBINS-I tool for the nonrandomized studies and the ROB 2 tool for the randomized controlled study1
| First author (reference) | Year | Bias due to confounding | Bias in selection of participants into the study | Bias in classification of interventions | Bias due to deviations from intended interventions | Bias due to missing data | Bias in measurement of outcomes | Bias in selection of the reported result | Overall risk of bias |
|---|---|---|---|---|---|---|---|---|---|
| ROBINS-I | |||||||||
| Alonso-Pedrero (28) | 2020 | Serious | Low | Moderate | Low | Moderate | Low | Low | Serious |
| Atzmon (29) | 2002 | Serious | Low | Serious | Low | Moderate | Moderate | Low | Severe |
| Bowman (30) | 2012 | Moderate | Low | Low | Low | Serious | Low | Low | Serious |
| Chang (31) | 2020 | Serious | Moderate | Low | Moderate | Low | Low | Low | Serious |
| Freitas-Simoes (32) | 2019 | Low | Low | Low | Low | Low | Low | Low | Low |
| García-Calzón (33) | 2015 | Low | Low | Low | Moderate | Low | Low | Low | Moderate |
| Gensous (34) | 2020 | Serious | Low | Low | Low | Low | Low | Low | Moderate |
| Handing (35) | 2019 | Moderate | Low | Low | Low | Low | Low | Moderate | Moderate |
| Nettleton (36) | 2008 | Moderate | Low | Low | Low | Low | Low | Low | Low |
| Praveen (38) | 2020 | Serious | Low | Low | Low | Low | Low | Low | Moderate |
| Seesen (39) | 2020 | Serious | Low | Low | Moderate | Low | Moderate | Low | Serious |
| Zwilling (40) | 2019 | Moderate | Low | Low | Low | Low | Low | Low | Low |
| Year | Bias due to randomization process | Bias due to deviations from intended interventions | Bias due to missing data | Bias in measurement of outcomes | Bias in selection of the reported result | Overall risk of bias | |
|---|---|---|---|---|---|---|---|
| ROB 2 | |||||||
| O'Callaghan (37) | 2014 | Some concerns | High | High | Low | High | High |
1
ROB 2, Risk of bias 2; ROBINS-I, Risk Of Bias In Non-randomised Studies—of Interventions.