Table 2.

Comparative characteristics of the study population and observance of COVID-19 preventive measures across surveys.

	Survey 1	Survey 2	Survey 3	p-Value
	n = 4124	n = 4703	n = 4543
	(April 2020)	(July 2020)	(Jan 2021)
Sociodemographic characteristics: n (%)
Age group				<0.001
18–20 years	1455 (35.3%)	1506 (32.0%)	1617 (35.6%)
21–30 years	2456 (59.6%)	2786 (59.2%)	2551 (56.2%)
31–40 years	158 (3.8%)	297 (6.3%)	262 (5.8%)
41–50 years	20 (0.5%)	65 (1.4%)	64 (1.4%)
51–60 years	28 (0.7%)	32 (0.67%)	39 (0.9%)
61 years and above	7 (0.2%)	17 (0.4%)	10 (0.2%)
Gender				0.004
Male	2490 (60.5%)	2768 (59.1%)	2837 (62.4%)
Female	1626 (39.5%)	1916 (40.9%)	1706 (37.6%)
COVID-19 preventive measures: n (%)
Mask use	2112 (51.2%)	2644 (56.2%)	2371 (52.2%)	<0.001
Observe 1.5 m physical distancing	2634 (63.9%)	2781 (59.1%)	2602 (57.3%)	<0.001
Wash hands regularly with soap	3334 (80.8%)	3491 (74.2%)	3560 (78.4%)	<0.001
Use alcohol-based hand gel regularly	2352 (57.0%)	2687 (57.1%)	2850 (62.7%)	<0.001
Cover mouth when coughing/sneezing	3606 (87.4%)	3875 (82.4%)	3937 (86.7%)	<0.001
Stay at home when feeling flu-like symptoms	3464 (84.0%)	3418 (72.7%)	3353 (73.8%)	<0.001
Travelled during the past 7 days	217 (5.3%)	827 (17.6%)	640 (14.1%)	<0.001
Adherence score category:				<0.001
0	193 (4.7%)	286 (6.1%)	279 (6.1%)
1	454 (11.0%)	639 (13.6%)	545 (12.0%)
2	728 (17.7%)	887 (18.9%)	915 (20.1%)
3	1134 (27.5%)	990 (21.1%)	998 (22.0%)
4	1615 (39.2%)	1901 (40.4%)	1806 (39.8%)
Willing to receive COVID-19 vaccine			3488 (76.8%)	NA
Reasons for COVID-19 vaccine refusal *				NA
(N = 1055 respondents who were unwilling)
Vaccine is ineffective			283 (26.8%)
Fear of side-effects			424 (40.2%)
COVID-19 is over, no need for vaccine			308 (29.2%)
My immune system is already very strong			204 (19.3%)
Other reasons **			29 (2.7%)

* Many responses possible for each participant. ** See details in Supplementary File S2.