Associations of KCNQ1 Polymorphisms with the Risk of Type 2 Diabetes Mellitus: An Updated Meta-Analysis with Trial Sequential Analysis

Table 1

Study characteristics from included studies in the meta-analysis.

First author	Year	Country	Ethnicity	Cases			Controls			Control source	Matching variables	SNP(s)^d	Score
				^a	Age (y)^b	Gender^c	^a	Age (y)^b	Gender^c
Lee YH	2008	Korea	Asian	908		48.4	502		53.6	Hospital	—	a	9
Unoki H (Japanese)	2008	Japan	Asian	5149	—	61.4	4176	—	47.6	Hospital	—	b, c, d	9
Unoki H (Chinese)	2008	China	Asian	1498		49.1	1881		44.0	Hospital	—	b, c, d	8
Unoki H (Danish)	2008	Denmark	Caucasian	4085		59.3	5032		53.7	Hospital	—	b, c, d	9
Yasuda K (Japanese)	2008	Japan	Asian	4378	—	—	4412	—	—	Population	—	a, b, f	12
Yasuda K (Chinese)	2008	China	Asian	1416		40.4	1577		46.1	Population	—	a, b	11
Yasuda K (Korean)	2008	Korea	Asian	758		46.7	632		45.4	Population	Gender	a, b	8
Yasuda K (Caucasian)	2008	Sweden	Caucasian	2830		58.9	3740		37.9	Population	Age	a, b	10
Hu C	2009	China	Asian	1769		52.1	1734		41.4	Hospital	—	a, b, c	7
Liu Y	2009	China	Asian	1912		41.1	2041		31.1	Population	—	a, b, c	10
Chen Z	2010	China	Asian	57	—	—	341	—	—	Hospital	—	a, b, c, d	6
Dehwah MAS	2010	China	Asian	223		44.8	201		44.3	Hospital	Gender	a	7
Han X	2010	China	Asian	1024		52.7	1005		34.1	Population	Age	a	11
Xu M	2010	China	Asian	66	—	—	652	—	—	Population	—	a	9
Wei Q	2010	China	Asian	133		51.1	106		50.9	Hospital	Age and gender	c, d, f	6
Zhang L	2010	China	Asian	100		58.0	97		53.6	Population	—	b	8
Been LF	2011	India and the USA	Caucasian	1428	—	—	1593	—	—	Population	—	a, b, e	13
Ohshige T	2011	Japan	Asian	2839	62.8	50.0	2125	51.6	50.0	Hospital	Gender	e	9
Saif-Ali R (Chinese)	2011	Malaysia	Asian	300		51.0	230		61.3	Hospital	Age	a, b, d	8
Saif-Ali R (Malay)	2011	Malaysia	Asian	234		45.3	117		45.8	Hospital	Age and gender	a, b, d	7
Tabara Y	2011	Japan	Asian	506	—	—	402	—	—	Hospital	—	a	8
Shi L	2011	China	Asian	171		56.1	288		60.1	Hospital	—	c, f	3
Van JV	2012	Netherlands	Caucasian	4620		43.3	5285		41.9	Population	Gender	a, b, f	12
Dai XP	2012	China	Asian	367		49.9	214		57.9	Hospital	Age	a, b	8
Iwata M	2012	Japan	Asian	724		62.3	763		47.1	Hospital	—	a, e	9
Lu S	2012	China	Asian	498		59.6	402		66.4	Hospital	—	e	8
Turki A	2012	Tunisia	Caucasian	900		37.8	600		45.5	Hospital	—	a, b, d, f	8
Gao X	2012	China	Asian	200		55.5	200		49.5	Hospital	Age	f	8
Wang J	2012	China	Asian	300		42.3	100		42.0	Hospital	Age and gender	e	7
Almawi WY	2013	Lebanon	Caucasian	995		58.8	1076		47.0	Hospital	Age	a, b	8
Wang H	2013	China	Asian	2533	53.3	59.6	2643	56.1	55.3	Population	Age and gender	a, b, c, d	10
Lin YD	2013	China	Asian	2925		37.5	3281		37.6	Population	Age and gender	a, b, c, e	11
Yang HL	2013	China	Asian	222		55.9	140		43.6	Hospital	—	a	6
Yu WH	2013	China	Asian	9221	58.1	48.5	4052	48.6	40.7	Population	—	a, b	11
Bazzi MD	2014	Saudi Arabia	Caucasian	90		50.0	95		52.6	Hospital	Age and gender	a	7
Sun ZH	2014	China	Asian	321	—	—	345	—	—	Hospital	—	c	8
Zhang LW	2014	China	Asian	349		55.9	300		60.3	Population	Age	a, c	11
Zhu AN	2014	China	Asian	238		55.9	240		55.8	Hospital	Age and gender	a	7
Khan IA	2015	India	Mixed	250		55.2	250		57.6	Hospital	Age and gender	d	7
Zhang W	2015	China	Asian	530		53.0	452		50.9	Hospital	Age and gender	a	8
Guo HL	2015	China	Asian	30		63.3	30		43.3	Hospital	Age	a	5
Shen Q	2015	China	Asian	922		51.5	925		46.4	Hospital	—	a	9
InterAct Consortium	2016	European countries	Mixed	6869	—	—	8708	—	—	Population	—	a	4
Cui LJ	2016	China	Asian	100		55.0	100		46.0	Hospital	Age	a, b	6
Gao K	2016	China	Asian	736	52.5 (43-61)	57.9	768	47.0 (39.0-57.0)	42.2	Population	—	f	11
Riobello C	2016	Spain	Caucasian	180	—	—	501	—	—	Population	—	a, b, e	11
Zhou X	2016	China	Asian	305		49.5	200		50.1	Hospital	Age and gender	a	8
Al-Shammari MS	2017	Saudi Arabia	Caucasian	320		54.4	516		56.0	Hospital	Age and gender	a, b, f	6
Baniasadian S	2018	Iran	Caucasian	77	—	45.5	90	—	48.9	Hospital	Gender	a	3
Plengvidhya N	2018	Thailand	Asian	500		67.2	500		71.2	Hospital	—	a	8
Chen JF	2018	China	Asian	84		59.5	104		55.8	Hospital	Age	a	6
Huang Q	2018	China	Asian	513		28.5	502		29.9	Population	Age and gender	a, f	13
Li YH (Uighur)	2018	China (Uighur)	Asian	282		48.2	99	—	49.5	Population	Gender	a, e	8
Li YH (Chinese Han)	2018	China (Chinese Han)	Asian	293		56.0	208	—	47.1	Population	—	a, e	10
Xu T	2018	China	Asian	100		68.0	100		57.0	Hospital	Age	a	5

SNP: single nucleotide polymorphism. ^aNumber, ^bage at survey, ^cpercentage of male, ^dSNPs: a: rs2237892; b: rs2237895; c: rs2237897; d: rs2283228; e: rs231362; f: rs151290.