Table 2 Quality assessment of cohort studies included in this meta- analysis 1
From: Consumption of coffee associated with reduced risk of liver cancer: a meta-analysis
Study | Representativeness of the exposed cohort | Selection of the unexposed cohort | Ascertainment of exposure | Outcome of interest not present at start of study | Control for important factor or additional factor2 | Outcome assessment | Follow-up long enough for outcomes to occur3 | Adequacy of follow-up of cohorts4 | Total quality scores |
|---|---|---|---|---|---|---|---|---|---|
Shimazu et al. [20], 2005 | ★ | ★ | ★ | ★ | ★★ | ★ | ★ | ★ | 9 |
Shimazu et al. [20], 2005 | ★ | ★ | ★ | ★ | ★★ | ★ | ★ | ★ | 9 |
Inoue et al. [21], 2005 | - | ★ | ★ | ★ | ★ | ★ | ★ | ★ | 7 |
Kurozawa et al. [22], 2005 | ★ | ★ | ★ | ★ | ★★ | ★ | ★ | - | 8 |
Hu et al. [23], 2008 | ★ | ★ | ★ | ★ | ★★ | ★ | ★ | ★ | 9 |
Inoue et al. [24], 2009 | - | ★ | ★ | ★ | ★★ | ★ | ★ | ★ | 8 |
Johnson et al. [25], 2011 | - | ★ | ★ | ★ | ★ | ★ | ★ | ★ | 7 |