| References | Risk of bias domains a | Tier b | |||||
|---|---|---|---|---|---|---|---|
| Exposure KEY | Outcome KEY | Confounding KEY | Inappropriate selection | Attrition | Other sources of bias/statistics | ||
| Houtkooper et al. ( 1995 ) | ++ | ++ | + | + | NR | + | 1 |
| Chan et al. ( 2011 ) | NR | + | + | NR | – – | – | 2 |
| de Jonge et al. ( 2015 ) | + | NR | ++ | ++ | – | + | 2 |
| Kaptoge et al. ( 2003 ) | + | + | + | ++ | + | + | 1 |
| Macdonald et al. ( 2004 ) | ++ | ++ | + | ++ | + | – | 1 |
| Promislow et al. ( 2002 ) | + | + | + | + | – – | + | 1 |
| Rejnmark et al. ( 2004 ) | + | ++ | ++ | ++ | + | + | 1 |
| Sugiura et al. ( 2016 ) | – | ++ | + | NR | NR | – | 2 |
a
Expert judgement was translated into a rating scale for each question to be answered as follows: (++): definitely low RoB; (+): probably low RoB; (NR): not reported; (−): probably high RoB; (− −): definitively high RoB.
b
The individual rating for each question was combined by an algorithm and translated to an overall tier of reliability for each individual study (RoB tier 1: low RoB; RoB tier 2: moderate RoB; RoB tier 3: high RoB).