Table 3.

Effect sizes–SHS and COPD

Nr.	Authors	Sex	RR (95 % CI)	log (rr)	se	n	w (%)
[72]	Chan-Yeung et al. (2007)	both sexes	1.64 (0.97–2.03)	0.49	0.19	578	25.96
[24]	McGhee et al. (2005)	both sexes	1.81 (1.24–2.65)	0.59	0.19	5,601	24.55
		men	1.50 (0.96–2.28)	0.41	0.22	3,098	100.00a
		women	2.59 (1.30–5.27)	0.95	0.36	2,503	24.69
[95]	Schwartz et al. (2009)	women	1.68 (1.12–2.61)	0.52	0.22	1,126	51.40
[75]	Wu et al. (2010)	women	3.12 (1.56–6.50)	1.14	0.36	410	23.91
[71]	Yin et al. (2007)	both sexes	1.60 (1.23–2.10)	0.47	0.14	15,379	49.49
		Sex	RR (95 % CI)	Q	p	I 2
	Synthesis	both sexes	1.66 (1.38–2.00)	0.28	0.871	0.00
		men	1.50 (0.96–2.28)a
		women	2.17 (1.48–3.18)	2.60	0.273	22.95

^asynthesis for men only based on McGhee et al. (2005)