Table 1. Characteristics of included studies in the meta-analysis.
| References | Country | Study design | Sample sizes | Age (yrs) | Outcomes | Definition of reference group | Estimation (95%CI) (Highest vs. lowest) |
|---|---|---|---|---|---|---|---|
| Abnet 2001 | China | Cohort | 28868 | 57(12)* | ESCC | None lost tooth | 0.90 (0.49–1.70) |
| Abnet 2005 | Finland | Cohort | 29124 | 57.2 ± 5.1# | ESCC | Lost ≤ 10 teeth | 0.73 (0.35–1.55) |
| Dye 2007 | China | CS | 579 | 40–67 | ESCC | Lost < 4 teeth | 1.45 (0.76–2.76) |
| Guha 2007 | Latin America | CC | 173/1805 | any age | ESCC | Lost ≤ 5 teeth | 1.07 (0.41–2.77) |
| Guha 2007 | Central Europe | CC | 132/928 | any age | ESCC | Lost ≤ 5 teeth | 1.80 (1.80–4.07) |
| Michaud 2008 | USA (White, Asian, Black) | Cohort | 48375 | 40–75 | EC | Lost ≤ 8 teeth | 1.34 (0.78–2.30) |
| Abnet 2008 | Iran | CC | 283/560 | 65(56–73)/65(57–72)* | ESCC | Lost ≤ 12 teeth | 1.79 (1.03–3.13) |
| Hiraki 2008 | Japan | CC | 354/708 | 20–79 | EC | Lost ≤ 11 teeth | 2.36 (1.17–4.75) |
| Dar 2013 | India | CC | 703/1664 | 61.6 ± 11.1/59.8 ± 11.1# | ESCC | None lost tooth | 1.08 (0.68–1.69) |
CS, cross-sectional; CC, case-control; EC, esophageal cancer; ESCC, esophageal squamous cell carcinoma;*, median (IQR);#, mean ± standard deviation.