Table 1:

Characteristics of included reports

Study location (Province)	Authors	Year of study	No. of patients	Recall rate	Incidence
Khuzestan	Aminzadeh et al[11]	2010	35655	0.0352	0.0020
Tehran	Ordoukhani et al[12]	2002	35067	0.0106	0.0010
Khorasan	Namakin et al[13]	2012	38987	0.0321	0.0183
Gilan	Kalantari et al[14]	2004	3000	0.0200	0.0010
Markazi	Dorreh et al[15]	2010	25658	0.0236	0.0030
Fars	Karamizadeh et al[16]	2012	63031	0.0200	0.0010
Isfahan	Hashemipour et al[17]	2007	113282	0.0320	0.0030
Kerman	Eftekhari et al[18]	2008	3000	0.0070	0.0010
Kurdistan	Nele et al[19]	2011	50539	0.0200	0.0020
Mazandaran	Akhi et al[20]	2011	45218	0.0460	0.0016
Ghazvin	Saffari et al[21]	2009	33488	0.0320	0.0020
Gilan	Mohtasham et al[22]	2007	9284	0.0315	0.0017
Yazd	Nouri Shadkam et al[23]	2008	13022	0.0620	0.0030
East Azerbaijan	Zeinalzadeh et al[24]	2011	62459	0.0250	0.0017
Kermanshah	Khassi et al[25]	2011	30265	0.0018	0.0017
West Azerbaijan	Eshratkhah et al[26]	2011	19141	0.0200	0.0020
Tehran	Mostafavi et al[27]	1995	1014	0.0800	0.0060
Tehran	Ordookhani et al[28]	2003	20107	0.0013	0.0010
Zanjan	Valizadeh et al[29]	2011	18008	0.0410	0.0010
Isfahan	Honarpisheh et al[30]	2002	500	0.0500	0.0100
Isfahan	Hashemipour et al[31]	2010	225224	0.0170	0.0020
Isfahan	Hashemipour et al[32]	2007	93381	0.0111	0.0030
Mazandaran	Haghshenas et al[33]	2012	10573	0.0200	0.0005
Isfahan	Ghasemi et al[34]	2013	464648	0.0210	0.0013
Mazandaran	Nasehi et al[35]	2010	10573	0.0140	0.0140