Skip to main content
. 2021 Jun 25;11:13304. doi: 10.1038/s41598-021-92452-0

Table 1.

Characteristics of study participants in the CHARLS, 2011–2015.

Characteristics Cleaner fuels use only (N = 3064), N (%) Solid fuels use reported in one or two surveys only (N = 2933), N (%) Consistent solid fuels use reported in all three surveys (N = 2671), N (%)
Age (years)
45–65 2265 (74.3) 2010 (68.9) 1664 (62.5)
Over 65 783 (25.7) 907 (31.1) 1000 (37.5)
Missing 16 16 7
Sex
Male 1322 (48.4) 1270 (48.6) 1165 (49.1)
Female 1420 (51.6) 1346 (51.4) 1209 (50.9)
Missing 10 7 11
Urbanicity of the living place
Rural 1003 (36.4) 1873 (71.5) 1993 (83.8)
Urban 1755 (63.6) 746 (28.5) 385 (16.2)
Expenditure in 2015 (RMB)
 ≤ 10,000 1845 (61.0) 2230 (77.1) 2115 (80.2)
10,000–50,000 932 (30.8) 549 (19.0) 457 (17.3)
50,000–100,000 128 (4.2) 69 (2.4) 42 (1.6)
> 100,000 118 (3.9) 44 (1.5) 24 (0.9)
Missing 41 41 33
Educational level
No formal 754 (27.4) 1178 (45.0) 1282 (53.9)
 ≤ 12 years 1872 (67.9) 1425 (54.5) 1083 (45.5)
 ≥ 12 years 130 (4.7) 16 (0.6) 13 (0.6)
Missing 3 2 0
Marital status
Married 2353 (85.3) 2129 (81.3) 1997 (84.0)
Not married 405 (14.7) 490 (18.7) 381 (16.0)
Smoking
Active 1229 (41.3) 1264 (44.3) 1192 (45.9)
Passive 803 (27.0) 760 (26.6) 695 (26.8)
Never 944 (31.7) 829 (29.1) 711 (27.4)
Missing 88 80 73
Cooking location within household
Yes 2933 (96.4) 2713 (93.2) 2424 (91.8)
No 111 (3.7) 198 (6.8) 218 (8.3)
Missing 20 22 29
Average hours of sleep at night
< 6 892 (29.1) 924 (31.5) 921 (34.5)
6–7 720 (23.5) 619 (21.1) 482 (18.1)
7–9 1227 (40.1) 1134 (38.7) 980 (36.7)
> 9 225 (7.3) 256 (8.7) 288 (10.8)
The number of unrested days per week
 < 1 1522 (55.2) 1345 (51.4) 1180 (49.6)
1–2 378 (13.7) 375 (14.3) 337 (14.2)
3–4 389 (14.1) 364 (13.9) 355 (14.9)
5–7 469 (17.0) 535 (20.4) 506 (21.3)