Table 3.
Customized downs and black checklist for bias risk assessment
| Author (years) | Reporting | External Validity | Internal Validity (bias) | Internal Validity—Confounding (selection bias) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| (1) | (2) | (3) | (6) | (7) | (9) | (10) | (11) | (18) | (20) | (21) | (22) | (26) | Total score | |
| Balci et al. 2021 [31] | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
*12/13 92.3% |
| Koc et al. 2022 [44] | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 0 |
*11/13 84.6% |
| Yeni, Tulek and Terzi, 2022 [45] | 1 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
*11/13 84.6% |
| Blakemore et al. 2021 [32] | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 |
*11/13 84.6% |
| Bonavita et al. 2021 [38] | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 |
*11/13 84.6% |
| Costabile et al. 2021 [39] | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 |
*11/13 84.6% |
| Garjani et al. 2021 [40] | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 |
*11/13 84.6% |
| Kitani-Morii et al. 2021 [33] | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 |
*11/13 84.6% |
| Suzuki et al. 2021 [34] | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 0 |
*11/13 84.6% |
| Motolese et al. 2020 [35] | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 |
*11/13 84.6% |
| Talaat et al. 2020 [37] | 1 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
*11/13 84.6% |
| Xia et al. 2020 [30] | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 0 |
*11/13 84.6% |
| Shaygannejad, Afshari-Safavi and Hatef, 2021 [41] | 1 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 0 |
*10/13 76.9% |
| Stojanov et al. 2021 [42] | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 0 |
*10/13 76.9% |
| Shalash et al. 2020 [29] | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 0 | 0 |
*10/13 76.9% |
| Stojanov et al. 2020 [36] | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 0 |
*10/13 76.9% |
| Goverover et al. 2022 [43] | 1 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 0 | 1 | 0 |
*9/13 69.2% |
| Salari et al. 2020 [28] | 1 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 0 | 0 |
8/13 61.5% |
| Studies which answered the criteria (%) |
18/18 100% |
18/18 100% |
7/18 38.9% |
18/18 100% |
18/18 100% |
7/18 38.9% |
18/18 100% |
18/18 100% |
14/18 77.8% |
18/18 100% |
15/18 83.3% |
16/18 88.9% |
5/18 27.8% |
|
Abbreviation: (0) No / Unable to determine; (1) Yes
(1) Is the hypothesis/aim/objective of the study clearly described? (2) Are the main outcomes to be measured clearly described in the Introduction or Methods section? (3) Are the characteristics of the patients included in the study clearly described? (6) Are the main findings of the study clearly described? (7) Does the study provide estimates of the random variability in the data for the main outcomes? (9) Have the characteristics of patients lost to follow‐up been described? (10) Have actual probability values been reported (e.g., 0.035 rather than < 0.05 for the main outcomes except Where the probability value is less than 0.001? (11) Were the subjects asked to participate in the study representative of the entire population from which they were recruited? (18) Were the statistical tests used to assess the main outcomes appropriate? (20) Were the main outcome measures used accurate (valid and reliable)? (21) Were the patients in different intervention groups (trials and cohort studies) or were the cases and controls (case‐control studies) recruited from the same population? (22) Were study subjects in different intervention groups (trials and cohort studies) or were the cases and controls (case‐control studies) recruited over the same period of time? (26) Were losses of patients to follow‐up taken into account?
*High methodological quality (score ≥ 9 [≥ 66.8%])