Table 1 Participant Characteristics.

From: A clean fuel cookstove is associated with improved lung function: Effect modification by age and secondhand tobacco smoke exposure

Categorical Variables

All (N = 200)

Biomass (N = 100)

LPG (N = 100)

N (%)

N

N

Smoker

   No

171 (85.5)

75

96

   Yes

29 (14.5)

25

4

   Hookah

16 (8.0)

16

0

   Bidi

19 (9.5)

15

4

   Cigarette

0 (0)

0

0

Secondhand Smoke Exposure

   No

83 (41.5)

21

62

   Yes

117 (58.5)

79

38

   Hookah

42 (21.0)

42

0

   Bidi

101 (50.5)

71

30

   Cigarette

31 (15.5)

14

17

Primary Cooking Area

   Indoors

118 (59.0)

20

98

   Any Ventilation

84 (42.0)

0

84

   4-Walls

10 (5.0)

2

8

   3-Wall

7 (3.5)

4

3

   2-Walls

11 (5.5)

14

34

Secondary Biomass Fuels

   Kerosene

26 (13.0)

20

6

   Wood

78 (39.0)

72

6

   Paper

24 (12.0)

24

0

   Twigs

45 (22.5)

44

1

   Polythene

25 (12.5)

24

1

   Charcoal

1 (0.5)

1

0

   Husk

11 (5.5)

11

0

Time spent cooking

   1–2 Hours

48 (24)

14

34

   2–4 Hours

123 (61.5)

66

57

   4–6 Hours

23 (11.5)

15

8

   >6 Hours

6 (3)

5

1

Years as Primary Cook

   1–3 years

15 (7.5)

2

13

   3–6 years

19 (9.5)

5

14

   >6 years

166 (83.0)

93

73

Continuous Variables

   Age (year; mean, SD)

33.3 (9.0)

35.1 (10.0)

31.4 (7.4)

   Education (years; median, IQR)

5.0 (0–8)

4.5 (0–7)

6.5 (0–10)

   Height (m; mean, SD)

1.52 (0.05)

1.54 (0.05)

1.51 (0.05)

   Weight (kg; mean, SD)

54.5 (11.0)

53.5 (10.2)

55.5 (11.8)

   FEV1 (L; mean, SD)

2.05 (0.40)

2.06 (0.44)

2.04 (0.35)

   FVC (L; mean, SD)

2.60 (0.45)

2.64 (0.49)

2.55 (0.39)

   FEF25–75 (L/s; mean/SD)

2.07 (0.86)

2.00 (0.96)

2.14 (0.73)

   FEV1/FVC ratio (%; mean, SD)

78.8 (7.01)

77.9 (7.06)

79.8 (6.86)

   PEF (L/s; mean, SD)

3.21 (0.64)

3.19 (0.68)

3.22 (0.61)