Table 1. Number of contacts by respondent characteristics, location, and time period.
Note that reduced denominators indicate missing data. Percentages may not total 100 because of rounding. The 95% confidence interval (CI) on the mean is calculated by bootstrap sampling and are weighted by day type (i.e., weekday or weekend) for diaries during post-lockdown period. *P < 0.05, **P < 0.01, ***P < 0.001. P values are taken from a weighted negative binomial regression, with a single binary variable distinguishing the post-lockdown period from the outbreak period. The weight refers to day type (i.e., weekday and weekend).
| Characteristics | Wuhan, mean (95% CI) | Shanghai, mean (95% CI) | Shenzhen, mean (95% CI) | Changsha, mean (95% CI) | ||||||||
| Baseline | Outbreak |
Post- lockdown |
Baseline | Outbreak |
Post- lockdown |
Baseline | Outbreak |
Post- lockdown |
Baseline | Outbreak |
Post- lockdown |
|
| Total number of contacts (participants) |
9,114 (624) | 1,245 (627) | 2,751 (822) | 17,201 (965) | 1,296 (557) | 2,232 (814) | 5,846 (741) | 1,798 (836) | 2,130 (837) | 7,025 (738) | 1,756 (813) | 1,930 (832) |
| Overall | 14.6 (13, 16.3) |
2 (1.9, 2.1) | 3.3 (3, 3.6)*** | 18.8 (17.5, 20.1) | 2.3 (2, 2.8) | 2.7 (2.5, 3)*** | 7.9 (7.2, 8.6) | 2.2 (2.1, 2.3) | 2.5 (2.4, 2.7)*** | 9.5 (8.6, 10.4) | 2.2 (2.1, 2.3) | 2.3 (2.1, 2.6) |
| Sex | ||||||||||||
| Male | 14.5 (12.2, 16.9) |
1.8 (1.7, 2) | 3 (2.8, 3.2)*** | 19 (17.3, 20.8) | 2.1 (1.9, 2.4) | 2.7 (2.4, 3)*** | 8.6 (7.7, 9.6) | 2.2 (2, 2.4) | 2.5 (2.3, 2.8)** | 9.8 (8.5, 11.1) | 2.3 (2.1, 2.4) | 2.6 (2.2, 3.2)* |
| Female | 14.7 (12.5, 17.1) |
2.1 (2, 2.3) | 3.6 (3.1, 4.1)*** | 18.5 (16.8, 20.2) | 2.6 (2.1, 3.4) | 2.8 (2.4, 3.2) | 7.2 (6.4, 8.1) | 2.1 (2, 2.2) | 2.5 (2.3, 2.8)*** | 9.3 (8.1, 10.7) | 2.1 (1.9, 2.2) | 2 (1.9, 2.2) |
| Age group | ||||||||||||
| 0–6 years | 8.6 (3.3, 17.8) | 2.2 (1.8, 2.8) | 2.7 (2.5, 2.9) | 11.6 (9.1, 14.3) | 1.9 (1.6, 2.1) | 2.5 (2.3, 2.8) | 7.2 (5.2, 9.5) | 2.5 (2.3, 2.8) | 2.5 (2.2, 2.8) | 10.9 (8, 14.4) | 2.7 (2.4, 3) | 2.7 (2.4, 3) |
| 7–19 years | 16.2 (12.4, 19.9) |
2.1 (2, 2.2) | 2.5 (2.3, 2.7) | 27 (23.9, 30.2) | 2.6 (2, 3.4) | 2.2 (2.1, 2.4) | 11.6 (9.6, 13.5) | 2.5 (2.2, 2.8) | 2.3 (2, 2.6) | 16.4 (13.3, 19.6) |
2.2 (2.1, 2.4) | 2.1 (1.9, 2.2) |
| 20–39 years | 15.3 (12.8, 18) |
2.1 (1.9, 2.2) | 4.7 (3.8, 5.7)*** | 22.4 (19.4, 25.2) | 2.2 (2, 2.5) | 3.4 (2.8, 4.2)*** | 8 (7, 9.1) | 1.8 (1.6, 2) | 2.9 (2.4, 3.4)*** | 9.1 (7.4, 11) | 2.2 (1.9, 2.6) | 2.8 (2.1, 3.9) * |
| 40–59 years | 13.8 (11.2, 16.8) |
2 (1.9, 2.1) | 3.7 (3.2, 4.2)*** | 19.9 (17.4, 22.6) | 2.8 (2, 4.2) | 3.2 (2.6, 3.8) | 8.5 (7, 10.4) | 2 (1.8, 2.3) | 2.6 (2.3, 3.1)** | 9.4 (7.7, 11.2) | 2.1 (1.9, 2.3) | 2.4 (2.1, 2.7) |
| ≥60 years | 13.9 (8.1, 21) | 1.4 (1.2, 1.7) | 2.4 (2.2, 2.7)*** | 12.6 (10.8, 14.3) | 1.6 (1.3, 1.9) | 2 (1.8, 2.2)* | 5 (4.3, 5.8) | 2.3 (2.1, 2.5) | 2.3 (2, 2.6) | 5.5 (4.7, 6.4) | 2 (1.8, 2.2) | 1.8 (1.6, 2) |
| Type of profession | ||||||||||||
| Preschool | 8.6 (3.5, 17.2) | 2.2 (1.7, 2.8) | 2.7 (2.5, 2.9) | 10.4 (8, 13.2) | 1.9 (1.7, 2.1) | 2.6 (2.3, 2.9) | 5.2 (3.4, 7.8) | 2.6 (2.2, 2.9) | 2.4 (2.1, 2.8) | 8.3 (5.3, 12) | 2.7 (2.3, 3.1) | 2.7 (2.3, 3.1) |
| Student | 14.6 (11.6, 18) |
2.1 (2, 2.3) | 2.5 (2.3, 2.7) | 26.2 (23.3, 29.3) | 2.5 (2, 3.2) | 2.3 (2.1, 2.5) | 11.8 (10.1, 13.8) |
2.5 (2.3, 2.9) | 2.4 (2.2, 2.7) | 16.5 (14, 19.5) | 2.3 (2.2, 2.5) | 2.2 (2, 2.3) |
| Employed | 15.4 (13.4, 17.6) |
2.1 (1.9, 2.2) | 4.5 (3.9, 5.2)*** | 22.5 (20.4, 24.7) | 2.5 (2.1, 3.3) | 3.6 (3, 4.2)*** | 9.3 (8.3, 10.3) | 2 (1.8, 2.2) | 3 (2.6, 3.4)*** | 10.3 (8.8, 12.1) | 2.2 (2, 2.4) | 2.8 (2.3, 3.6)*** |
| Working age not in the labor force |
14.1 (6, 24.6) | 1.8 (1.3, 2.4) | 2.8 (2.3, 3.3)* | 14.5 (7.3, 24.2) | 1.8 (1.3, 2.3) | 2.3 (1.9, 2.9) | 5.9 (3.6, 9.4) | 1.8 (1.5, 2.1) | 1.8 (1.3, 2.3) | 5.5 (4.1, 7.3) | 2.1 (1.8, 2.4) | 1.9 (1.6, 2.2) |
| Retired | 12.1 (7.7, 17.2) |
1.5 (1.3, 1.7) | 2.4 (2.2, 2.6)*** | 11.8 (10.2, 13.3) | 1.6 (1.4, 1.8) | 2 (1.8, 2.1)* | 4.7 (4.2, 5.4) | 2.2 (2, 2.3) | 2.2 (2, 2.4) | 5.2 (4.5, 6) | 1.9 (1.7, 2.1) | 1.8 (1.6, 2) |
| Household size | ||||||||||||
| 1 | 10.5 (5, 17.6) | 0.6 (0.1, 1.4) | 2.2 (1.1, 3.7)** | 15.2 (10.5, 20.2) | 0.3 (0.2, 0.5) | 0.4 (0.2, 0.8) | 5.5 (4.1, 7.1) | 0.8 (0.6, 1.1) | 1 (0.6, 1.3) | 5.5 (3.8, 7.8) | 1 (0.4, 1.9) | 0.7 (0.3, 1.2) |
| 2 | 12.6 (7.9, 17.8) |
1.1 (0.9, 1.2) | 1.9 (1.6, 2.3)*** | 14.5 (12.5, 16.6) | 1.4 (1.1, 1.8) | 1.4 (1.2, 1.7) | 6.4 (4.8, 8.1) | 1.3 (1.2, 1.4) | 1.9 (1.5, 2.5)*** | 6.6 (5.4, 8) | 1.4 (1.2, 1.6) | 1.4 (1.2, 1.6) |
| 3 | 14.8 (12.5, 17.3) |
1.9 (1.8, 2) | 3.4 (2.9, 3.9)*** | 20.3 (18.5, 22.1) | 2.2 (2.1, 2.4) | 2.7 (2.4, 3.1)*** | 8.8 (7.9, 9.7) | 2.3 (2.1, 2.5) | 2.8 (2.6, 3.1)*** | 11.3 (9.6, 13) | 2.2 (2.1, 2.3) | 2.3 (2.1, 2.4) |
| 4 | 11.9 (9.2, 15.4) |
2.3 (2.2, 2.5) | 3.4 (3.2, 3.6)*** | 20.3 (16.6, 24.7) | 3 (2.8, 3.2) | 4.2 (3.5, 5.1)*** | 8.4 (7.2, 10) | 3.1 (2.9, 3.2) | 3.1 (2.9, 3.3) | 10.8 (8.5, 13.7) | 3 (2.8, 3.1) | 3.7 (2.7, 5.4)* |
| ≥5 | 21.5 (16.2, 27.5) |
3.2 (2.9, 3.5) | 5.7 (4.8, 6.8)*** | 21.4 (18.1, 25.4) | 5.9 (3.9, 9.2) | 5 (4.1, 6.7) | 10.2 (8.3, 12.3) | 4.3 (4.1, 4.5) | 4.3 (4, 4.6) | 11.3 (8.9, 14.2) | 3.9 (3.7, 4.1) | 4.2 (3.8, 4.6) |