Table 3.
Quality assessment of included studies
| Study 1st author, year | Study design | Q1 | Q2 | Q3 | Q4 | Q5 | Q6 | Q7 | Q8 | Q9 | Q10 | Q11 | Q12 | Q13 | Q14 | Overall RoB |
| Arendt-Nielsen,42 2014 | CS | Y | Y | Y | Y | N | NA | NA | Y | Y | NA | Y | N | NA | Y | 8/10=80% low |
| Imamura,43 2015 | CS | Y | Y | Y | N | N | NA | NA | Y | Y | NA | N | Y | NA | N | 6/10=60% moderate |
| Lee,44 2011 | CS | Y | N | Y | Y | N | NA | NA | Y | Y | NA | Y | NR | NA | N | 6/10=60% moderate |
| Li,45 2020 | CS | Y | Y | Y | Y | N | NA | NA | Y | Y | NA | Y | NR | NA | N | 6/10=60% moderate |
| Neogi,50 2016 | C | Y | Y | Y | Y | N | Y | Y | Y | Y | Y | Y | Y | N | Y | 12/14=86% low |
| Petersen,49 2016 | CC | Y | Y | Y | Y | N | Y | CD | Y | N | Y | Y | Y | / | / | 9/12=75% moderate |
| Radojčić,46 2017 | CS | Y | Y | Y | Y | N | NA | NA | Y | Y | NA | Y | NR | NA | Y | 8/10=80% low |
| Sofat,47 2019 | CS | N | Y | Y | Y | Y | NA | NA | Y | Y | NA | Y | Y | NA | Y | 9/10=90% low |
| Tchetina,48 2020 | CS | Y | Y | Y | Y | N | NA | NA | Y | Y | NA | Y | NR | NA | N | 7/10=70% moderate |
<7 (50%)→<7 (50%)→high RoB=poor quality; 7–10 (50%–75%)→moderate RoB=fair quality; 11–14 (>75%)→low RoB=good quality.
C, cohort; CC, case–control; CD, cannot determine; CS, cross-sectional; N, no; NA, not applicable; NR, not reported; RoB, risk of bias; Y, yes.