Table 13.

Coherence. Hazard ratio (HR) and 95% confidence interval (CI) for survival of patients with glioblastoma multiforme and use of wireless phones in different age groups, study period 1997–2009 [55].

	Mobile phone			Cordless phone			Wireless phone
	n, exp	HR	95% CI	n, exp	HR	95% CI	n, exp	HR	95% CI
Glioblastoma multiforme (n = 926)
Age, first use
<20 years old	10	2.24	1.04–4.85	6	1.78	0.68–4.67	11	2.27	1.10–4.71
20–49 years old	296	1.24	0.98–1.58	177	1.31	1.001–1.72	328	1.23	0.99–1.53
≥50 years old	226	1.11	0.91–1.36	232	1.09	0.88–1.34	279	1.14	0.95–1.37