Table 1. Baseline characteristics and methodological quality of included studies focused on the relationships of PTTG expression and invasiveness in pituitary adenomas.

First author [Ref]	Country	Year	Tumor invasiveness		Gender (M/F)	Age (years)	Detection method	NOS score
			Invasion PAs	Non-invasion PAs
Sun HL [12]	China	2013	29	23	29/23	65.0 (60∼72)	Immunohistochemistry	7
Zhang Y [32]	China	2012	22	41	-	-	Immunohistochemistry	5
Shen YL [33]	China	2012	45	18	27/36	41 (8∼67)	Immunohistochemistry	8
Mo K [26]	China	2011	28	22	23/27	14–68	Immunohistochemistry	7
Wu JS [34]	China	2010	26	22	26/22	46.0±0.5	Immunohistochemistry	7
Zhou J [35]	China	2008	29	20	23/26	-	Immunohistochemistry	6
Wang YS [36]	China	2008	21	27	28/20	36.5±9.7	Immunohistochemistry	7
Li J [25]	China	2008	34	17	28/23	39.0 (17∼68)	Immunohistochemistry	7
He XL [37]	China	2008	15	28	21/27	47.5 (19∼73)	Immunohistochemistry	7
Li AJ [38]	China	2007	26	24	17/33	42.7±11.7	Immunohistochemistry	7
ZY [27]	China	2006	30	25	33/27	39.2 (17∼70)	Immunohistochemistry	7
Hu JF [39]	China	2006	12	28	17/23	45.5 (17∼74)	Immunohistochemistry	7
Li YY [40]	China	2006	30	25	-	-	Immunohistochemistry	6
Wang F [24]	China	2005	38	17	20/35	36.0 (22∼65)	Immunohistochemistry	7
Liu JN [41]	China	2004	20	10	18/12	41.5 (20∼72)	Immunohistochemistry	5

PAs  =  pituitary adenomas; M  =  male; F  =  female; NOS  =  Newcastle-Ottawa Scale.