Methodological quality evaluation of the 18 studies included in the meta-analysis
| Study | Major components of JBI checklist for cross-sectional studies | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Were the criteria for inclusion in the sample clearly defined? | Were the study subjects and the setting described in detail? | Was the exposure measured in a valid and reliable way? | Were objective criteria used for measurement of the condition? | Were confounding factors identified? | Were strategies to deal with confounding factors stated? | Were the outcomes measured in a valid and reliable way? | Was appropriate statistical analysis used? | ||
| Chen et al. (2013) | Yes | Yes | Yes | Unclear | Yes | Unclear | Yes | Yes | |
| Baker et al. (2014) | Yes | Yes | Yes | Yes | Unclear | Unclear | Yes | Yes | |
| Sanchez-Contreras et al. (2014) | Yes | Yes | Yes | Yes | Unclear | Unclear | Yes | Yes | |
| Nicolas et al. (2015) | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | |
| Anheim et al. (2016) | Yes | Yes | Yes | Yes | Unclear | Unclear | Yes | Yes | |
| David et al. (2016) | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | |
| Gebus et al. (2017) | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | |
| Ramos et al. (2018) | Yes | Yes | Yes | Yes | Yes | Unclear | Yes | Yes | |
| Giorgio et al. (2019) | Yes | Yes | Yes | Yes | Unclear | Unclear | Yes | Yes | |
| Grangeon et al. (2019) | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | |
| Chelban et al. (2020) | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | |
| Kurita et al. (2021) | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | |
| Study | Items of Newcastle-Ottawa Scale for case–control studies | ||||||||
| Selection | Comparability | Exposure | Total | ||||||
| (1) | (2) | (3) | (4) | (1) | (2) | (3) | |||
| Nicolas et al. (2013a) | ★ | ★ | ★ | ★ | ★★ | ★ | ★ | ★ | 9 |
| Hozumi et al. (2018) | ★ | ★ | ★ | ★ | ★★ | ★ | ★ | ★ | 9 |
| Study | Items of Newcastle-Ottawa Scale for cohort studies | ||||||||
| Selection | Comparability | Outcome | Total | ||||||
| (1) | (2) | (3) | (4) | (1) | (2) | (3) | |||
| Hsu et al. (2013) | ★ | ★ | ★ | ★ | ★★ | ★ | ✩ | ✩ | 7 |
| Chen et al. (2020) | ★ | ★ | ★ | ★ | ★★ | ★ | ★ | ✩ | 8 |
| Chen et al. (2019) | ★ | ★ | ★ | ★ | ★★ | ★ | ★ | ✩ | 8 |
| Guo et al. (2019) | ★ | ★ | ★ | ★ | ★✩ | ★ | ★ | ✩ | 7 |
NOS scare for case–control studies: selection, (1) is case definition adequate, (2) representativeness of the cases, (3) selection of controls, (4) definition of controls; comparability, comparability on basis of design or analysis; exposure, (1) ascertainment of exposure, (2) same method of ascertainment for cases and controls, (3) nonresponse rate. NOS scale for cohort studies: Selection, (1) representativeness of the exposed cohort, (2) selection of the nonexposed cohort, (3) ascertainment of exposure to implants, (4) demonstration that outcome of interest was not present at start of study; comparability: comparability of cohorts on the basis of the design or analysis; outcome, (1) assessment of outcome, (2) was follow-up long enough for outcomes to occur, (3) adequacy of follow-up cohorts.