PM2.5 concentrations by type of venue and type of smoking area in 2013 and 2018 in Vietnam
| 2013 | 2018 | |||||
| Geometric mean (95% CI) | Mean (SD) | Median (min-max) | Geometric mean (95% CI) | Mean (SD) | Median (min-max) | |
| Type of venues* | ||||||
| Restaurants | 79.0 (73.2 to 85.4) | 132.3 (167.9) | 61 (15–996.2) | 50.4 (49.0 to 51.8) | 60.5 (45.8) | 50.5 (9.3–627.5) |
| Coffee shops | 99.5 (92.0 to 107.5) | 150.0 (158.7) | 85.1 (20–892.2) | 62.1 (58.9 to 65.4) | 87.4 (87.5) | 65.9 (1.3–845.9) |
| Cafeterias | 87.9 (80.4 to 96.0) | 130.5 (125.4) | 76.5 (13–768.6) | 52.2 (49.7 to 54.8) | 71.1 (75.6) | 60.1 (6.2–934.8) |
| Smoking area* | ||||||
| Smoking-observed area | 167.5 (157.6 to 178.1) | 228.6 (181.9) | 191.0 (31–996.2) | 71.7 (68.8 to 74.6) | 109.6 (114.7) | 69.5 (8.7–934.8) |
| Non-smoking area | 48.5 (46.9 to 50.2) | 54.1 (27.9) | 48 (13–443.6) | 42.9 (41.6 to 44.3) | 52.6 (28.1) | 50.8 (1.3–142.8) |
| Outdoor environment | 65.5 (60.9 to 70.4) | 74.7 (49.1) | 60.8 (32.3–385.6) | 52.3 (50.9 to 53.6) | 62.1 (37.3) | 61.5 (4.3–845.9) |
| Total of all venues | 87.7 (83.7 to 91.9) | 137.7 (154.5) | 70 (13–996.2) | 55.2 (53.7 to 56.7) | 73.6 (73.6) | 58.0 (1.3–934.8) |
*, Kruskal-Wallis test showed a significant difference in median within groups.