Study design
A web-based cross-sectional survey based on the National Internet Survey on Emotional and Mental Health (NISEMH) was used to collected data from participants regarding their demographic information, knowledge about the COVID-19, amount of time focusing on the COVID-19, and psychological impact. Our web-based survey of the COVID-19 was broadcasted on the Internet through the WeChat public platform and mainstream social platforms (such as Weibo, online forums, etc.). People using WeChat or other social tools may see our questionnaire request, and answered the survey by scanning the QR code of the questionnaire address or clicking the relevant link. This web-based questionnaire was completely voluntary and non-commercial.
Participants
The target population of this study are the quarantined population. We identified the participants through the following items: Which of the following identities best described your actual situation? (1) Not ill but quarantined; (2) Suspected infected; (3) Confirmed cases; or (4) Not sure. According to the purpose of our study, only subjects belonging to category (1) will be included in our analysis.
Data collection and quality control
In this study, participants answered the questionnaires anonymously on the Internet (via computer or smartphone) from February 3, 2020, to February 17, 2020. All subjects reported their demographic data, knowledge about the COVID-19 pandemic, and three standardized scales, which were used to evaluated their anxiety disorders, depressive symptoms, and sleep quality. To ensure the quality of the survey, we have set the response range of some items (e.g., the age range was limited to 18-80 years old, some items needed to be answered in reverse) and encouraged participants to answer carefully through questionnaire explanations. Furthermore, we restricted each electronic device to answer the survey once by identifying the unique IP address. Considering that a small number of voluntary participants may answer randomly or have difficulty understanding the items of our survey, questionnaires that were completed <1 minute or >60 minutes would be excluded from the analysis. Finally, a total of 6,961 participants who completed the questionnaires were included in our study.
Psychological impacts
Anxiety disorders
Chinese version of Generalized Anxiety Disorder-7 (GAD-7) scale was used to assess the individual’s anxiety symptoms. The GAD-7 has been validated in the Chinese cultural context and has been previously used [15, 16]. Seven items assess the frequency of anxiety symptoms over the past two weeks on a 4-point Liker-scale ranging from 0 (never) to 3 (nearly every day). The total score of GAD-7 ranged from 0 to 21, with increasing scores indicating a more severe functional impairments as a result of anxiety symptoms [17]. In this study, we defined a GAD-total score ≥ 9 points as the presence of anxiety disorders [15].
Depressive symptoms
We used the Center for Epidemiology Scale for Depression (CES-D) in the Chinese version to identify whether participants had showed a symptoms of depression [18], and the Chinese version of this scale has been validated and extensively utilized in the Chinese population [18, 19]. Total of twenty items assess the frequency of depressive symptoms over the past 2 weeks on a 4-point Liker-scale ranging from 0 (rarely or none of the time) to 3 (most or all of the time). The score range of the CES-D is 0-60 points, and higher scores indicated a more severe depressive symptoms [20]. In this study, CES-D scores > 28 points indicated depressive symptoms.
Poor sleep
The Chinese version of the Pittsburgh Sleep Quality Index (PSQI) scale was used to evaluated the subject’s sleep disorders over the past 2 weeks [21]. The PSQI scale contains seven components (subjective sleep quality, sleep duration, sleep latency, habitual sleep efficiency, use of sleep medications, sleep disturbance, and daytime dysfunction), and the score for each component ranging from 0 to 3 points. The global PSQI score ranges from 0 to 21, with higher scores indicated more a severe poor sleep [22]. The Chinese version of PSQI has been demonstrated to be reliable and valid in the Chinese population [21], a global PSQI score > 7 points indicated poor sleep quality.
Demographic information
Demographic data included gender, age, and individual occupations. Occupation included the following four types: (1) Healthcare workers, which included doctors, nurses, and health-related administrators; (2) Enterprise or institution workers, which consisted of enterprise employees, national/provincial/municipal institution workers, and other relevant staff; (3) Teachers or students, which included teachers or students from universities, middle schools, or elementary schools; and (4) Others, which consisted of freelancers, retiree, social worker, and other relevant staff.
Times spent focusing on the COVID-19
Times spent focusing on the COVID-19 pandemic was used to measure the average time (in hours) the participants spent focusing on the COVID-19 information each day, by asking the participants on: “How much time (in hours) do you spend focusing on the COVID-19 outbreak each day on average? (Including reading outbreak information on the TV news and/or mobile phone, discussing the progress of the outbreak with family or friends, etc.)”.
Knowledge about the COVID-19
The knowledge about the COVID-19 pandemic was evaluated by the following 5 judgment questions:
- Inhalation of droplets from sneezing, coughing, or talking of an infected person could cause infection;
- Contact with something contaminated by an infected person could lead to infection; c. The incubation period of the virus does not exceed 14 days;
- Contact with an asymptomatic person might also lead to infection;
- There are already targeted drugs that could cure the disease.
Of the above 5 questions, one point was given for correct answers, and no points were given for incorrect or uncertain answers. Participants with scores equal to 5 points, equal to 4 points, and ≤3 points were considered to be “Knowledgeable”, “Generally knowledgeable”, and “Not knowledgeable”.
Statistical analysis
First, descriptive analyses were conducted to describe the demographic characteristics and knowledge about the COVID-19 in the quarantined population. Second, the prevalence of anxiety disorders, depressive symptoms, and poor sleep stratified by gender, age, and occupations were reported, and the Chi-square test (χ2) was used to compare the differences between groups. Third, univariate and multivariate logistic regression models were performed to explore the potential risk factors for psychological impact of the quarantined population. Odds ratio (OR), adjusted odds ratio (AOR), and 95% confidence interval (95% CI) were obtained from logistic regression models. All data were analyzed using Statistical Package for Social Sciences (SPSS) version 24.0. P-values of less than 0.05 were considered statistically significant (2-sided tests).