Table 4.

Comparison of studies performed before and after 2011.

Study	OR	CI Lower Limit	CI Upper Limit	Weight
Santino et al., 2004 [45]	6.50	2.26	18.73	13.92%
Tomao et al., 2005 [46]	0.67	0.22	2.04	13.43%
Cisak et al., 2005 [47]	8.93	3.00	26.60	13.62%
Rojko et al., 2005 [48]	2.91	1.30	6.53	16.90%
Cisak et al., 2008 [49]	7.71	2.20	27.03	11.98%
Kaya et al., 2008 [50]	0.78	0.03	17.93	3.41%
Buczek et al., 2009 [51]	2.09	1.45	3.02	22.93%
Di Rienzi et al., 2010 [52]	1.67	0.11	24.94	4.71%
Until 2010	3.03	1.39	6.61	47.14%
Cisak et al., 2012 [54]	2.55	0.59	11.00	8.16%
Tabibi et al., 2013 [56]	0.59	0.15	2.42	8.56%
Jovanovic, 2015 [57]	1.00	0.10	10.31	3.93%
Bucak, 2016 [60]	0.54	0.19	1.53	14.26%
De Keukeleire et al., 2016 [61]	2.46	0.51	11.85	6.98%
Cora et al., 2017 [65]	0.89	0.56	1.41	41.29%
De Keukeleire et al., 2017 [66]	2.03	0.80	5.16	16.81%
After 2011	1.08	0.63	1.85	52.86%
Combined effect size	1.76	0.58	5.29