Demographics
During the survey, 1196 participants completed the online questionnaire. Of these participants, 148 reported being retired or currently unemployed, or did not provide their occupation. Thus, the questionnaires from 1048 participants were deemed valid for subsequent analysis (Table 1). Among the 1048 participants, 68% were female; regarding age, 21% were 18-29 years, 28% 30-39 years, 33% 40-49 years, 16% 50-59 years, and 3% 60 years and over. Over half of the participants (53%) were married or cohabited, and only 6% were living alone. Around 75% had attained undergraduate education at university or above. The majority of participants (91%) worked on a full-time basis. With regards to occupation, 42% were professionals, 24% associated professionals, 17% managers or administrators, and 10% clerical support workers. Our study sample comprised fewer participants from worker groups and more from professional groups than would have been representative according to Hong Kong statistics on the labour force and employed population. In the analysis, the four occupation groups of service/sales/craft workers, plant/machine operators and assemblers, elementary workers, and other were grouped as “manual labourers,” who comprised around 6% of the study sample (Table 1)
Personal protection behaviours for prevention of COVID-19
Compliance with the four behavioural categories comprising eight personal protective behaviours was evaluated. Regarding hand hygiene, of the 1048 survey participants, 77.1% reported always washing hands before meals, and 97.5% reported always washing hands after using the toilet, but only 56.4% always used alcohol-based hand rub when outside. Regarding face mask use, 95.4% always wore a face mask when outside. As for household hygiene behaviours, only 19.9% and 16.5% always used disinfectant to clean toilets and drain-pipes, respectively. Regarding social distancing behaviours, 51.2% reported they always avoided leaving their home and 63.2% always avoided contact with their neighbours (Table 2).
Compliance with personal protection behaviours by socio-demographic and occupation groups
Personal protection behaviours differed between socio-demographic subgroups in terms of age, gender, living arrangement, marital status, educational level and work status (Table 1). Younger persons tended to wash hands more frequently after using the toilet (P = 0.014) but less frequently before meals (P = 0.049). Females were more likely to always perform protection behaviours, especially using alcohol hand rub (61.9% vs. 44.6% for males), avoiding leaving home (54.8% vs.43.5% for male), and avoiding contacting neighbours (66.6% vs.56.0% for males). The cohabiting participants showed a lower frequency of several behaviours than their single, married, divorced, and widowed counterparts, namely handwashing before meals (60.9%, P = 0.011), wearing mask (87.0%, P<0.001), and avoiding contact with neighbours (43.5%, P<0.001), while those who were single, divorced, or widowed reported a lower frequency of avoiding leaving home (P = 0.008). As for living arrangements, there was a clear pattern that participants living alone were less likely to perform protective behaviours than those living with others. In addition, there were no significant differences according to education attainment or work status for most of behaviours, except that those who finished higher secondary school reported lower frequency of using disinfectant in toilets (P= 0.034), and full-time employees were less likely to always avoid contact with neighbours (61.8% vs 76.5% for part-time, P = 0.017) (Table 2).
Personal protection behaviour patterns in different occupations were mostly alike, except for manual laborers, who reported a slightly lower frequency of such behaviours. In the two-way cross tabulation analysis of occupation and frequency of behaviours (Table 2), a significant difference between occupations was only found for putting disinfectant into toilets (P = 0.042), with 24.0% of managers and administrators and 24.2% of associate professionals always performing this behaviour, and only 15.4% of manual laborers always doing so. For handwashing, approximately 78% of the combined professionals (i.e. managers and administrators, professionals, associated professionals, and clerical workers) always washed hands before meals, and around 98% of them always washed hands after using the toilet, while manual labourers reported slightly lower frequencies for these two behaviours (69.2% and 92.3% for handwashing before meals and after using toilet, respectively), although the differences were not significant. Around 90.8% of manual labourers wore a face mask, while at least 94% individuals from the combined professionals always did so. As for social distancing, there was a lower proportion of manual labourers (53.9%) who always avoided contact with their neighbours in comparison with combined professionals (over 60%), despite the difference was not statistically significant.
Relationship between personal protection behaviours and workplace guidelines
It was found that 89.9% of participants reported that relevant guidelines and measures were available in their workplace, while fewer manual laborers (76.9%) reported such availability (P = 0.003). The association between personal protection behaviours and availability of workplace guidelines and measures was examined (Table 3). After adjustment for covariates, individuals with available guidelines and measures in their workplace tended to report higher frequency of handwashing before meals (adjusted odds ratio [OR]: 4.21, 95% confidence interval [CI]: 1.62-10.95), handwashing after toilet use (adjusted OR: 7.54, 95% CI: 1.27-44.72), wearing a face mask (adjusted OR: 4.25, 95% CI: 1.02-17.76), and avoiding contact with neighbours (adjusted OR: 2.79, 95% CI: 1.15-6.76).
The significant ORs for the interaction terms of workplace policy availability and occupation presented in Table 3 suggest that the association between workplace policy availability and personal protection behaviours was different between occupational groups. The association was also examined for different occupation groups separately (Table 4). The association between workplace policy availability and personal protection behaviours was found to be significant for managers and administrators, as well as manual labourers, with adjustment for covariates, while no significant association was found for other occupations. Among managers and administrators, the availability of workplace guidelines was found to be associated with handwashing before meals (adjusted OR: 4.56, 95% CI: 1.64-12.63), wearing a face mask (adjusted OR: 9.52, 95% CI: 1.79-50.53), avoiding leaving home (adjusted OR: 2.73, 95 %CI: 1.04-7.16), and avoiding contact with neighbours (adjusted OR: 4.98, 95% CI: 1.81-13.72). Among manual laborers, the availability of guidelines was associated with handwashing before meals (adjusted OR: 4.76, 95% CI: 1.10-20.69), using alcohol-based hand rub for disinfection (adjusted OR: 6.21, 95% CI: 1.54-25.12), avoiding leaving home (adjusted OR: 9.42, 95% CI: 2.14-41.56), and avoiding contact with neighbours (adjusted OR: 4.58, 95% CI: 1.09-19.22). Although a significant association was found, the standard errors were relatively large, and 95% CIs were also wide because of a relatively small sample size for a few behaviours and occupational groups; thus, the interpretation of point estimates of adjusted ORs should take this into consideration.