Skip to main content

Table 1 Extracted data characteristics

From: Association between smoking and the risk of acute mountain sickness: a meta-analysis of observational studies

Research

Altitude (m)

Sample size

AMS

Normal

Diagnosis of AMS with cut-off value

Age (mean)

BMI (mean)

Sex (m/f)

Smoking

Non-smoking

Smoking

Non-smoking

Smoking

Non-smoking

AMS

Normal

AMS

Normal

AMS

Normal

Ren, 2015 [14]

4300

16

64

3

32

13

32

LLS > 3

38.1

38.6

24.7

26.2

9/26

22/23

Wu, 2012 [17]

4525

182

200

71

102

111

98

LLS >3 OR LLS >4

      

You, 2012 [19]

4300

138

176

36

83

102

93

LLS > 4

20.08

20.25

21.31

21.47

119/0

195/0

MacInnis, 2013 [26]

4380

147

344

42

125

105

219

LLS ≥ 3

    

100/67

244/80

Mairer, 2010(a) [28]

3454

9

66

4

26

5

40

LLS ≥ 4

35.1

34.5

23.4

23.3

25/5

39/6

Mairer, 2010(b) [28]

3817

13

67

3

25

10

42

36.2

38.1

23.5

22.8

22/6

41/11

Mairer, 2009 [27]

3500

61

370

12

58

49

312

LLS ≥ 4

38.4

37.2

23.7

23.3

50/20

266/86

Schneider, 2002(a) [4]

4559

56

331

16

103

40

228

ESQ ≥ 0.70

38.2

22.6

314/73

Schneider, 2002(b) [4]

4559

72

368

21

99

51

269

37.0

22.7

359/81

  1. Mairer (2010) [28] reported two studies (2010a and 2010b) that were independent. Schneider (2002) [4] also published two studies (2002a and 2002b) that were independent. Schneider (2002) [4] used the Environmental Symptom Questionnaire (ESQ) to diagnose AMS using an ESQ cut-off value of 0.70, which corresponded to a Lake Louise Score (LLS) of 4. Wu (2012) [17] did not provide original data regarding age, gender or BMI. MacInnis (2013) [26] did not provide clear data regarding age or BMI. Schneider (2002) [4] provided only data regarding the total population of subjects. In addition, we analyzed how the studies defined smoking and found that only one article (Wu (2012) [17]) provided the following clear definition of smoking: “A smoker was someone who smoked 10 or more cigarettes/day for >6 months”