| References | Risk of bias domains (a) | Tier (b) | |||||
|---|---|---|---|---|---|---|---|
| Exposure KEY | Outcome KEY | Confounding KEY | Inappropriate selection | Attrition | Other sources of bias/statistics | ||
| Bacharach et al. ( 2017 ) | + | + | −− | NA | NA | − | 2 |
| Baer (1984) | NR | NR | −− | NA | NA | − | 3 |
| Berger and Schaumburg (1984) | NR | + | −− | NA | NA | − | 2 |
| Blackburn and Warren (2017) | NR | NR | −− | NA | NA | − | 3 |
| Brush et al. ( 1988 ) | − | −− | −− | −− | NR | −− | 3 |
| Chaudary et al. ( 2003 ) | − | −− | NR | NR | + | − | 3 |
| Chaudary and Cornblath (2013) | + | + | −− | NA | NA | − | 2 |
| Dalton and Dalton (1987) | + | −− | −− | NR | ++ | − | 2 |
| Dalton ( 1985 ) | + | NR | −− | NA | NA | −− | 2 |
| Falcone and Sowa (2013) | + | NR | −− | NA | NA | −− | 2 |
| Foca ( 1985 ) | + | + | −− | NA | NA | −− | 2 |
| Franzblau et al. ( 1996 ) | + | + | NR | NR | + | − | 2 |
| Friedman et al. ( 1986 ) | NR | + | −− | NA | NA | − | 2 |
| Gdynia et al. ( 2008 ) | + | + | −− | NA | NA | − | 2 |
| Kaur et al. ( 2014 ) | + | + | −− | NA | NA | − | 2 |
| Keniston et al. ( 1997 ) | + | + | + | − | + | − | 2 |
| Malek et al. ( 2020 ) | + | + | −− | NA | NA | − | 2 |
| No authors listed ( 2009 ) | NR | NR | −− | NA | NA | −− | 3 |
| No authors listed ( 2020 ) | NR | NR | −− | NA | NA | −− | 3 |
| Parry and Bredesen (1985) | NR | − | −− | NA | NA | −− | 3 |
| Schaumburg et al. ( 1982 ) | NR | + | −− | NA | NA | − | 2 |
| Schaumburg et al. ( 1983 ) and No authors listed (1984) | NR | + | −− | NA | NA | − | 2 |
| Scott et al. ( 2008 ) | + | + | −− | NA | NA | − | 2 |
| Shrim et al. ( 2006 ) | −− | −− | −− | NR | ++ | − | 3 |
| Stewart et al. ( 2022 ) | + | + | + | + | − | + | 1 |
| van Hunsel et al. ( 2018 ) | NR | −− | −− | NA | NA | − | 3 |
| Vasile et al. ( 1984 ) | −− | + | −− | NA | NA | − | 2 |
| Visser et al. ( 2014 ) | + | + | + | − | ++ | + | 1 |
| Vrolijk et al. ( 2020 ) | − | −− | −− | NA | NA | −− | 3 |
| Waterston and Gilligan (1987) | −− | + | −− | NA | NA | − | 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).