Evaluation of Mobile Phone and Cordless Phone Use and Glioma Risk Using the Bradford Hill Viewpoints from 1965 on Association or Causation

Table 3

Consistency. Numbers of cases (Ca), controls (Co), and odds ratio (OR) with 95% confidence interval (CI) for glioma and latency in three different case-control studies, Interphone 2010 (mobile phone) [2], Coureau et al. 2014 (mobile phone) [39], and Hardell and Carlberg 2015 (wireless phones) [38].

	Interphone; Appendix		Coureau et al.; 2014		Hardell and Carlberg; 2015		Meta-analysis
	Ca/Co	OR; (95% CI)	Ca/Co	OR; (95% CI)	Ca/Co	OR; (95% CI)	Ca/Co	OR; (95% CI)
Unexposed	93/159	(1.0); —	107/219	(1.0); —	306/1,058	(1.0); —	506/1,436	(1.0); —
Latency
2–4 years	460/451	1.68; (1.16–2.41)	49/122	0.88; (0.56–1.39)	215/575	1.17; (0.95–1.44)	724/1,148	1.22; (0.90–1.66)
5–9 years	468/491	1.54; (1.06–2.22)	66/111	1.34; (0.87–2.06)	339/799	1.27; (1.05–1.54)	873/1,401	1.33; (1.13–1.55)
10+ years	190/150	2.18; (1.43–3.31)	22/31	1.61; (0.85–3.09)	520/1,098	1.39; (1.15–1.67)	732/1,279	1.62; (1.20–2.19)

Unexposed Interphone Appendix : latency 1–1.9 years; unexposed in Coureau et al.: not regular user; unexposed Hardell and Carlberg: no use + latency ≤ 1 year.
1–4 years in Coureau et al.