TABLE 1.
Demographic characteristics of participants (Shanghai, China. 2018–2019).
| Characteristic | Smoking group (n = 27) | Non-smoking group (n = 27) | p Value |
|---|---|---|---|
| Age, y | 29.06 (22.11, 46.09) | 30.09 (25.05, 37) | 0.99 |
| Sex-male, n (%) | 18 (66.7) | 16 (59.3) | 0.78 |
| Height, m | 171 (166, 177.8) | 167.2 (161.5, 171.7) | 0.14 |
| Weight, kg | 71.8 (66.9,81.1) | 68.3 (55.9,74.8) | 0.13 |
| BMI, kg/m2 | 24.1 (22.6,27.4) | 22.8 (20.4, 25.9) | 0.18 |
| Education levels | 0.09 | ||
| Junior middle school, n (%) | 3 (11.1) | 0 (0) | |
| High school, n (%) | 2 (7.4) | 1 (3.7) | |
| University, n (%) | 18 (66.7) | 12 (44.4) | |
| Postgraduate, n (%) | 4 (14.8) | 14 (51.9) | |
| Employment status | 0.30 | ||
| Employed part-time, n (%) | 2 (7.4) | 1 (3.7) | |
| Employed full-time, n (%) | 13 (48.1) | 16 (59.3) | |
| Student, n (%) | 9 (33.3) | 10 (37) | |
| Retired, n (%) | 3 (11.1) | 0 (0) | |
| Economy-income level | 0.08 | ||
| None | 7 (25.9) | 4 (14.8) | |
| Less than 3,000 ¥ per month | 2 (7.4) | 6 (22.2) | |
| 3,000–5,000 ¥ per month | 7 (25.9) | 1 (3.7) | |
| 5,000–10000 ¥ per month | 5 (18.5) | 7 (25.9) | |
| More than 10,000 ¥ per month | 6 (22.2) | 9 (33.3) | |
| Marital status | 0.85 | ||
| Unmarried, n (%) | 14 (51.9) | 12 (44.4) | |
| Married, n (%) | 11 (40.7) | 13 (48.1) | |
| Divorced, n (%) | 2 (7.4) | 2 (7.4) | |
| Occupation time, h | 8 (8, 10) | 8 (8, 9) | 0.74 |
| Leisure time, h | 7 (6, 8) | 8 (7, 8) | 0.17 |
| Moderate-intensity physical activity per week | 0.35 | ||
| <75 min per week, n (%) | 6 (22.2) | 10 (37) | |
| 75–150 min per week, n (%) | 6 (22.2) | 7 (25.9) | |
| >150 min per week, n (%) | 15 (55.6) | 10 (37) | |
| Site of LBP | 0.37 | ||
| Left, n (%) | 7 (25.9) | 3 (11.1) | |
| Right, n (%) | 4 (14.8) | 8 (29.6) | |
| Middle, n (%) | 9 (33.3) | 8 (29.6) | |
| Both two sides, n (%) | 7 (25.9) | 8 (29.6) | |
| Low back pain Occurrence | 0.77 | ||
| Continuous, n (%) | 8 (29.6) | 9 (33.3) | |
| Interinittent, n (%) | 19 (70.4) | 18 (66.7) | |
| History of low back pain, y | 4.42 (3.33, 7.58) | 4.17 (3.58, 9.83) | 0.92 |
| Duration of first onset, d | 7 (2, 60) | 7 (2, 21) | 0.43 |
| Duration of low back pain per day, h | 6 (2, 10) | 6 (3, 12) | 0.60 |
| Nature of pain | 0.14 | ||
| Sore and Distended pain, n (%) | 16 (59.3) | 20 (74.1) | |
| Radiation pain, n (%) | 2 (7.4) | 4 (14.8) | |
| Needling pain, n (%) | 2 (7.4) | 0 (0) | |
| Other, n (%) | 7 (25.9) | 3 (11.1) | |
| Pain mode in 24 h | 0.98 | ||
| Gradually aggravated, n (%) | 10 (37) | 9 (33.3) | |
| Gradually relieved, n (%) | 7 (25.9) | 7 (25.9) | |
| No change, n (%) | 6 (22.2) | 6 (22.2) | |
| Other, n (%) | 4 (14.8) | 5 (18.5) |
Non-parametric test analysis was used for continuous variables and χ2 test was used for non-continuous variables. The numeric variables in the table were shown as median and Interquartile range.
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); y, year; n, number; h, hour; 1 US dollar = 6.3734 ¥.