Table 1.
Demographic characteristics of COVID-19 patients
| Social-demographic profile | Included(a) | Excluded(b) |
P value (a) vs. (b) |
||
|---|---|---|---|---|---|
| No. | % | No. | % | ||
| Total | 164 | 100 | 885 | 100 | |
| Age group (years) | |||||
| Mean ± s.d. | 44.2 ± 15.8 | 40.5 ± 17.0 | – | 0.010 | |
| Median (range) | 42 (5–79) | 38 (0–102) | – | 0.072 | |
| Below 30 | 37 | 22.6 | 293 | 33.1 | 0.095 |
| 30–39 | 36 | 22.0 | 176 | 19.9 | |
| 40–49 | 27 | 16.5 | 138 | 15.6 | |
| 50–59 | 29 | 17.7 | 141 | 15.9 | |
| 60–69 | 26 | 15.9 | 91 | 10.3 | |
| 70 and above | 9 | 5.5 | 46 | 5.2 | |
| Gender | |||||
| Male | 77 | 47.0 | 526 | 59.4 | 0.003 |
| Female | 87 | 53.0 | 359 | 40.6 | |
| Residence status | |||||
| Singapore resident | 121 | 73.8 | 631 | 71.5 | 0.544 |
| Non-Singapore resident | 43 | 26.2 | 252 | 28.5 | |
| Nationality | |||||
| Singapore | 109 | 66.5 | 550 | 62.4 | 0.092 |
| UK | 10 | 6.1 | 38 | 4.3 | |
| Malaysia | 8 | 4.9 | 32 | 3.6 | |
| China | 7 | 4.3 | 28 | 3.2 | |
| Indonesia | 7 | 4.3 | 29 | 3.3 | |
| Philippines | 7 | 4.3 | 25 | 2.8 | |
| Australia | 4 | 2.4 | 16 | 1.8 | |
| India | 4 | 2.4 | 57 | 6.5 | |
| Bangladesh | 3 | 1.8 | 31 | 3.5 | |
| New Zealand | 2 | 1.2 | 2 | 0.2 | |
| France | 1 | 0.6 | 9 | 1.0 | |
| Myanmar | 1 | 0.6 | 3 | 0.3 | |
| South Africa | 1 | 0.6 | 0 | 0.0 | |
| Germany | 0 | 0.0 | 7 | 0.8 | |
| USA | 0 | 0.0 | 13 | 1.5 | |
| Others | 0 | 0.0 | 42* | 4.8 | |
| Source of infection | |||||
| Imported | 31 | 18.9 | 508 | 57.4 | <0.001 |
| Local cases | 133 | 81.1 | 377 | 42.6 | |
| Incubation period (days)† | |||||
| Mean ± s.d. | 5.5 ± 2.3 | – | – | – | |
| Median (range) | 5.0 (1–12) | – | – | – | |
| 1–3 days | 24 | 14.6 | – | – | – |
| 4–6 days | 92 | 56.1 | – | – | – |
| 7–9 days | 37 | 22.6 | – | – | – |
| 10–15 days | 11 | 6.7 | – | – | – |
| Day of illness at admission (days)‡ | |||||
| Mean ± s.d. | 5.7 ± 3.5 | 6.0 ± 4.6 | 0.454 | ||
| Median (range) | 5.0 (1–17) | 5.0 (1–41) | 0.720 | ||
| 1–3 days | 49 | 31.0 | 259 | 33.6 | 0.651 |
| 4–6 days | 57 | 36.1 | 243 | 31.6 | |
| 7–9 days | 32 | 20.3 | 149 | 19.4 | |
| 10–15 days | 17 | 10.8 | 91 | 11.8 | |
| >15 days | 3 | 1.9 | 28 | 3.6 | |
*
Included Spain (5), Switzerland (4), the Netherlands (3), Japan (3), Brazil (3), Sri Lanka (2), Sweden (2) and others.
†
Incubation period = Date of symptom onsets – Date of exposure + 1 day.
‡
Day of illness at admission = Date of admission – Date of symptom onsets + 1 day.
Noted:
(i) Missing values of included cases: Day of illness at admission (6);
(ii) Missing values of excluded cases: Nationality (3), Residence status (2), Day of illness at admission (115).