Table 1 Details of the selected studies for meta-analysis.

Bag et al.2014

25,097,401

26/33

56.11 ± 9.22

28.68 ± 6.77

24 M, 2F

33 M

(23/08)

North

Shukla et al.2013

23,803,127

218/238

56.14 ± 11.91

56.15 ± 7.84

189 M,29F

191 M,47F

128/34

North

Sobti et al.2004

15,646,021

100/76

55.5 ± 11.3

50.9 ± 8.1

95 M,5F

73 M,3F

86/59

North

Sharma et al.2015

26,529,288

270/270

57.39 ± 10.60

53.23 ± 10.49

235 M,35F

233 M,37F

212/193

North

Kumar et al.2009

19,009,239

93/253

42.6 ± 6.3

39.8 ± 5.4

81 M,12F

203 M,50F

81/101

North

Ihsan et al.2014

25,027,082

154/154

59.16 ± 9.95

60.39 ± 10.43

38 M,116F

38 M,116F

105/71

East

Phukan et al.2014

24,815,479

230/460

59.01 ± 13.02

58.60 ± 13.99

230F

460F

126/153

East

Ihsan et al.2011

22,206,016

188/209

60.41 ± 10.58

57.19 ± 10.75

145 M,43F

159 M,50F

132/139

East

Sreeja et al.2008

18,472,644

111/111

57.82 ± 11.74

56.21 ± 10.36

82 M,29F

84 M,27F

44/19

South

Peddireddy et al.2016

27,090,234

246/250

57.57 ± 10.19

58.06 ± 9.56

177 M,69F

180 M,70F

106/63

South

Sreeja et al.2005

16,228,113

146/146

58.17 ± 10.95

56.06 ± 10.67

133 M,13F

128 M,18F

102/62

South

Sobti et al.2008

18,415,801

151/151

56.9 ± 10.4

56.4 ± 11.1

130 M,21F

123 M,28F

123/112

North

Shah et al.2008(a)

18,573,508

200/200

56 ± 9

43 ± 12

200 M

200 M

120/62

North

Singh et al.2010

22,072,123

200/200

53 ± 10

51 ± 09

200 M

200 M

117/64

North

Saikia et al.2014

24,716,924

272/544

61.96 ± 11.91

61.79 ± 12.21

130 M,142F

260 M,284F

197/341

East

Natukula et al.2013

24,175,813

100/101

56.14

48.07

73 M,27F

86 M,15F

51/36

South

Uppal et al.2014

25,584,213

100/100

63.70 ± 3.91

62.08 ± 2.88

64 M ,36 F

76 M, 24F

76/56

North

Sreeja et al.2008(a)

17,952,468

211/211

57.82 ± 11.74

56.21 ± 10.36

182 M,29F

184 M,27F

143/119

South

Pachouri et al.2007

17,417,947

103/122

Not Reported

Not Reported

90 M,13F

104 M,18F

80/28

North

Sobti et al.2009

19,558,213

151/151

56.9 ± 0.4

56.4 ± 1.1

130 M, 21F

123 M,28F

123/112

North

Sobti et al.2003

14,602,525

100/76

55.59 ± 11.3

50.99 ± 8.1

95 M,5F

73 M,3F

86/59

North

Ihsan et al.2011(a)

21,043,833

161/274

60.24 ± 10.77

53.21 ± 13.37

120 M, 41F

202 M,72F

110/139

East

Jain et al.2005

16,354,872

40/40

Not Reported

Not Reported

35 M, 5F

35 M, 5F

32/32

North

Kumari et al.2016

27,614,750

420/420

57.87 ± 10.39

52.14 ± 10.9

359 M, 61F

353 M, 67F

345/303

North

Singh et al.2016

27,707,541

330/325

57.9 ± 10.58

52.27 ± 10.84

285 M, 45F

265 M, 60F

268/223

North

Tilak et al.2013

23,317,414

175/202

56.5 ± 10.3

54.99 ± 8.1

169 M, 06F

191 M, 11F

146/159

North

Girdhar et al.2016

27,396,354

353/351

57.55 ± 10.69

52.84 ± 10.80

305 M,48F

300 M,51F

278/250

North

Shah et al.2008(b)

18,082,227

294/263

56 ± 9

43 ± 12

200 M,0F

200 M,0F

120/62

North

Shaffi et al.2009

19,827,888

190/248

52.7

53.2

87 M,22F

95 M,68F

84/98

North

Lawania et al.2017

29,035,087

370/370

58.11 ± 10.44

53.83 ± 10.18

319 M,51F

319 M,51F

303/271

North

Bahl et al.2017(a)

27,640,551

300/300

57.38 ± 10.74

53.23 ± 10.44

258 M,42F

253 M,47F

235/208

North

Bahl et al.2017(b)

28,378,643

303/305

57.38 ± 10.74

53.23 ± 10.44

262 M,41F

269 M,36F

239/223

North

Bahl et al.2018

30,346,805

181/31

57.87 ± 10.81

Not Reported

184 M,28F

Not Reported

171/0

North

Singh et al.2017

28,332,164

193/48

58.71 ± 10.38

0

215 M,26F

0

200/0

North

Bhardwaj et al. 2017

29,412,865

250/237

57.38 ± 10.74

53.23 ± 10.44

252 M,40F

241 M,22F

229/197

North

Bahl et al.2017(c)

29,749,862

292/263

57.38 ± 10.74

53.23 ± 10.44

252 M,40F

241 M,22F

229/197

North

Chowdhury et al.2015

25,921,167

50/50

55 ± 10

46 ± 11

40 M, 10F

39 M, 11F

44/Not Reported

East

Islam et al.2013

23,178,447

106/116

57.87 ± 10.12

58.14 ± 9.77

93 M, 13F

105 M, 11F

97/104

East

Masood et al.2016

27,461,642

252/270

54 ± 11.5

53 ± 12.6

184 M, 68F

197 M, 73F

131/78

North