Table 1.

Characteristics of the included studies for this meta-analysis.

First-author	Year	Country	Genotyping methodsa	Quality score	Sample size		APOE genotypes distribution (case/control)
					Case	Control	ε2/ε2	ε2/ε3	ε3/ε3	ε3/ε4	ε4/ε4	ε2/ε4	ε2	ε3	ε4	ε2/ε2+ ε2/ε3	ε3/ε4+ ε4/ε4
Hong	2017	China	RT-PCR	10	114	106	1/1	14/11	61/72	31/20	2/0	5/2	21/15	167/175	40/22	15/12	33/20
Chaudhary	2012	Thailand	PCR-RFLP	12	147	155	1/1	11/2	88/117	46/30	1/4	0/1	13/5	233/266	48/39	12/3	47/34
Halim	2012	Egypt	PCR-RFLP	5	35	35	6/0	5/2	18/31	6/2	0/0	0/0	17/2	47/66	6/2	11/2	6/2
Al-Majed	2011	Kuwaiti	PCR-RFLP	9	41	105	3/7	1/2	21/73	4/6	12/15	0/2	7/18	47/154	28/38	4/9	16/21
Vaisi-Raygani	2010	Iran	PCR-RFLP	12	172	118	4/0	31/26	91/69	31/20	12/3	3/0	42/26	244/184	58/26	35/26	43/23
Shi	2009	China	PCR-RFLP	9	98	110	0/0	4/3	44/71	36/27	2/0	12/9	16/12	128/172	52/36	4/3	38/27
Izar	2009	Brazil	PCR-RFLP	11	386	604	3/7	60/86	241/388	57/81	9/4	14/31	80/131	599/943	89/120	63/93	66/85
Chaaba	2008	Tunisia	PCR-RFLP	9	71	86	0/0	3/9	57/68	NA	NA	0/1	NA	NA	NA	3/9	11/8
Zhang L	2008	China	PCR-RFLP	10	100	100	2/4	12/15	54/67	30/13	2/1	0/0	16/23	150/162	34/15	14/19	32/14
Guo	2007	China	Multi-ARMS-PCR	11	40	40	0/0	2/1	22/29	13/7	1/0	2/3	4/4	59/66	17/10	2/1	14/7
Pan	2002	China	PCR-RFLP	11	24	63	0/1	4/7	12/45	6/8	0/0	2/2	6/11	34/105	8/10	4/8	6/8
Zhang WH	2000	China	PCR-RFLP	9	61	63	1/0	2/7	46/50	10/6	1/0	1/0	5/7	104/113	13/6	3/7	11/6
Zheng	1998	China	PCR-RFLP	8	33	78	NA	NA	22/59	NA	NA	NA	NA	NA	NA	3/15	8/4

^aMulti-ARMS-PCR: multiplex amplification refractory mutation system-polymerase chain reaction; PCR-RFLP: polymerase chain reaction restriction fragment length polymorphism; RT-PCR: real-time polymerase chain reaction.

NA: not available.