Pandemic-related health literacy: a systematic review of literature in COVID-19, SARS and MERS pandemics

Abstract

Introduction:

Health literacy plays an essential role in one’s ability to acquire and understand critical medical information in the coronavirus disease 2019 (COVID-19) infodemic and in other pandemics. We aimed to summarise the assessment, levels and determinants of pandemic-related health literacy and its associated clinical outcomes.

Methods:

A systematic review was performed in Medline^®, Embase^®, PsycINFO^®, CINAHL^® and four major preprint servers. Observational and interventional studies that evaluated health literacy related to the novel COVID-19, severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) were included. Items used in health literacy instruments were grouped under the themes of knowledge, attitudes and practices. Determinants of health literacy were grouped into five domains: sociodemographic, medical, psychological/psychiatric, health systems-related and others.

Results:

Of the 2,065 articles screened, 70 articles were included. Of these, 21, 17 and 32 studies evaluated health literacy related to COVID-19, SARS and MERS, respectively. The rates of low pandemic health literacy ranged from 4.3% to 57.9% among medical-related populations and from 4.0% to 82.5% among nonmedical populations. Knowledge about the symptoms and transmission of infection, worry about infection, and practices related to mask usage and hand hygiene were most frequently evaluated. Sociodemographic determinants of health literacy were most frequently studied, among which higher education level, older age and female gender were found to be associated with better health literacy. No studies evaluated the outcomes associated with health literacy.

Conclusion:

The level of pandemic-related health literacy is suboptimal. Healthcare administrators need to be aware of health literacy determinants when formulating policies in pandemics.

INTRODUCTION

With the rapid progression of the novel coronavirus disease 2019 (COVID-19) into a pandemic infecting over 2.5 million patients worldwide, the need to gather and synthesise health-related information to effect timely behavioural changes has become essential.[1,2] This comes in the wake of an ‘infodemic’ with evolving scientific knowledge about the infection being generated daily, which has led to reversals in infection prevention recommendations made within a short span of time.[2,3,4] For example, the use of cloth mask during the early stages of the COVID-19 pandemic was discouraged by the World Health Organization due to uncertainty about its efficacy.[3] However, its potential use in slowing the spread of COVID-19 has led to subsequent recommendations by the US Centers for Disease Control and Prevention for it to be worn by healthy individuals.[4] The ease of access to information via social and online media platforms has also become a double-edged sword in this pandemic, where there has been substantial propagation of misinformation.[5] Faced with the continuous influx of information related to the COVID-19 pandemic, an individual’s level of health literacy exerts a vital role in one’s ability to acquire, discern and understand accurate medical information.

Health literacy is broadly defined as the “level of capacity one has to obtain, process and understand basic health information and services needed to make appropriate health decisions”.[6] Inadequate levels of health literacy have remained a pervasive problem worldwide, despite medical advances in the past decades. A review by Paasche-Orlow et al. involving 85 studies reported that 26% of people living in the USA had low general health literacy.[7] Similar findings were reported in Europe, where 47% of the population was found to have limited health literacy.[8] In the setting of noncommunicable diseases, the association of health literacy with increased healthcare costs, morbidity and mortality is well established.[9] Equal importance of health literacy in communicable diseases was highlighted in the recent COVID-19 crisis and previous coronavirus pandemics such as the severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS).[1,10] In contrast to the general health literacy required for the prevention or management of chronic diseases, these pandemics require an individual’s readiness and adaptive ability in developing their pandemic-related and critical health literacy quickly. This is critical as the rapid and successful implementation of control measures for infectious diseases requires the collective compliance of all individuals.[11,12]

Varying levels of pandemic-related health literacy have been reported. In a study that examined COVID-19 awareness and attitudes among chronic disease patients in the USA, it was worrisome to note that one-third of participants were unable to identify symptoms associated with COVID-19 and 24.6% of participants felt that they were not likely to contract the virus.[13] Another study conducted by Roy et al. showed that only 43% of responders regarded COVID-19 as a contagious disease and 18.2% regarded fever as a symptom of COVID-19.[14] In contrast, a study in China showed that health literacy was high among participants, where a 90% accuracy rate was reported for the COVID-19 knowledge questionnaire administered. For other coronavirus pandemics such as SARS and MERS, differences in pandemic-related literacy levels across different study populations were also reported.[15,16]

Variations in general health literacy have been linked to multiple determinants ranging from education to socioeconomic statuses.[17] Likewise, this is expected for pandemic-related health literacy. Understanding the levels and determinants of pandemic-related health literacy across different populations is essential for healthcare policymakers to formulate optimal strategies for effective communication of critical medical information in the COVID-19 crisis and future pandemics.

Hence, the primary objective of this review was to evaluate and summarise the assessment and level of health literacy related to COVID-19, SARS and MERS and its associated determinants. In the absence of a gold standard instrument, the themes identified from items used in the health literacy instruments across studies will guide the development of future pandemic-related health literacy instruments. The secondary objective of this study was to evaluate the clinical outcomes associated with poor pandemic-related health literacy.

METHODS

This systematic review has been registered on the International Prospective Register of Systematic Reviews (PROSPERO) (registration number: CRD 42020181171).

Data sources and searches

The literature search was conducted in Medline^®, Embase^®, PsycINFO^® and CINAHL^®, in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) checklist. Due to the relative novelty and recent nature of the COVID-19 pandemic, preprints from four widely used databases, which included arXiv, bioRxiv, medRxiv and Social Science Research Network (SSRN), were extracted for evaluation. Keywords employed in the search strategy included terms related to health literacy as well as the viruses and syndromes implicated in the COVID-19, MERS and SARS pandemics. Terms related to health literacy were adapted from reviews that evaluated health literacy in other patient populations.[18,19] The full search strategy is detailed in Supplemental Digital Appendix 1. The start date of the search was unrestricted and current as of 22 April 2020.

Study selection

Full-text articles, both peer reviewed and non-peer reviewed, in the English language were retrieved from the eight databases. Studies that evaluated health literacy related to COVID-19, SARS or MERS among adult participants aged ≥18 years old from the general population, healthcare sectors and infected patients were included. For the study designs, both interventional and observational studies, such as cohort, cross-sectional and case–control studies, were included. Case series, case reports, other irrelevant meta-analyses and systematic reviews were excluded. We also excluded studies that evaluated paediatric populations and nonhuman subjects.

Two independent reviewers (Seng JJB and Yeam CT) performed the screening and inclusion of articles. All disagreements encountered during the review process were discussed. In situations where disagreements could not be resolved, a third independent reviewer (Huang CW) arbitrated to achieve consensus.

Data extraction and quality assessment

Data extracted included the sociodemographic and clinical characteristics of the study participants, such as age, race/ethnicity, education levels, income levels, study designs, instruments used for assessment of health literacy, the definition of health literacy used in studies, level of health literacy, factors associated with health literacy and clinical outcomes associated with health literacy.

For the risk of bias assessment, the Quality Assessment Tool for Studies by the National Health, Lung and Blood Institute was adopted to evaluate the methodological quality of the included articles.[20] Each study was rated as low, moderate or high risk of bias by two independent reviewers (Seng JJB and Yeam CT) based on the responses obtained from the ten items. In situations where insufficient information was available to score an item, the authors of the study were contacted for clarification. If the authors could not be contacted, the item was rated as high risk of bias. All disagreements were resolved via discussion between the two reviewers. Only studies that were rated as low and moderate risk of bias were included in this review.

Data synthesis and analysis

Descriptive statistics were used to summarise the characteristics of the included studies. With regard to the level of health literacy, we reported the average percentage of correct answers or the percentage of participants with low health literacy as defined by the cut-offs described in each study, where available. As there are no gold standard health literacy instruments developed for COVID-19, SARS or MERS,[21] significant heterogeneity is expected in the types of tools used for assessment of health literacy across participants. Consequently, meta-analysis could not be performed. The rates of pandemic-related health literacy were compared between Asian and non-Asian countries, as well as between high-income and low- and moderate-income economies as defined by the World Bank. High-income nations were defined as those having an average gross national income of US$12,696 or more in the year 2020.

In the literature, there is currently no consensus on the optimal level of health literacy across various populations. However, extrapolating from the United States of Health and Human Services report, only 15% of adults had health literacy below the basic level.[22] Hence, for the purpose of this review, suboptimal pandemic health literacy is defined as poor health literacy, which is greater than or equal to 15%.

Questions from instruments used across the included studies were classified into three main themes: knowledge, attitudes and practices, to help guide future development of standardised COVID-19 and pandemic health literacy tools. The analyses were segregated by medical and nonmedical populations due to the expected differing levels of health literacy in the two populations. For studies where the questionnaires were not available, study authors were contacted for the questionnaire. If there were no replies from the authors, the themes were extracted from the description of the questionnaires in the main text. A framework for the core items to be included in pandemic health literacy tools was also proposed based on the common themes assessed across studies.

Factors associated with better health literacy were categorised into five domains, which encompassed sociodemographic, medical, psychological/psychiatric, health systems related and others. A narrative review has been provided for the factors evaluated among the included studies. Clinical outcomes associated with poor health literacy among patients infected with COVID-19, MERS and SARS included time from illness onset to seeking medical treatment, hospitalisation and duration of hospitalisation, admission to intensive care unit (ICU) and length of ICU stay, need for ventilator support, recovery from infection and reinfection.

RESULTS

Figure 1 shows the flowchart for the inclusion of articles. A total of 1,965 published articles and 40 preprints were retrieved. After removal of duplicates, exclusion of irrelevant articles and inclusion of articles identified from hand searching, a total of 70 articles were included in this review. The percentage of concordance during the initial article screening was 90%. Details pertaining to the study designs and characteristics of participants among the included studies are presented in Supplemental Digital Appendix 2 ^{(905KB, pdf)} . Pertaining to the risk of bias, 48 (68.5%) and 22 (31.4%) studies were rated as low and moderate risk of bias, respectively. No studies were rated as high risk of bias [Supplemental Digital Appendix 3]. Majority of studies that were labelled as moderate risk of bias suffered from poor study participant rates of less than 50%. However, these are common limitations that hinder studies conducted during pandemics due to limited participant movement during lockdowns. Table 1 shows a summary of the characteristics of the included studies. Majority of the included studies were cross sectional in design (n = 65, 92.9%) and were conducted during the pandemics (n = 69, 98.6%). Twenty-one (30%) studies recruited more than 1,000 participants.

Figure 1.

Flowchart shows the inclusion of articles for review. SSRN: Social Science Research Network.

Table 1.

Overview of included studies (N=70).

Variable	Number of studies (%)
	COVID-19 (n=21)	SARS (n=17)	MERS (n=32)	Overall (n=70)
Period of study
During epidemic/pandemic	21 (100)	16 (94.1)	32 (100)	69 (98.6)
After epidemic/pandemic	0 (0)	1 (5.9)	0 (0)	1 (1.4)
Continent of studya
Asia	15 (71.4)	14 (82.4)	30 (93.8)	59 (84.3)
Europe	1 (4.8)	2 (11.8)	2 (6.3)	5 (7.1)
North America	3 (14.3)	1 (5.9)	0 (0)	4 (5.7)
Multi-continent	1 (4.8)	0 (0)	0 (0)	1 (1.4)
Africa	1 (4.8)	0 (0)	0 (0)	1 (1.4)
Country of study
Saudi Arabia	0 (0)	0 (0)	27 (84.4)	27 (38.6)
Hong Kong	0 (0)	7 (41.2)	0 (0)	7 (10)
India	4 (19)	0 (0)	0 (0)	4 (5.7)
The USA	3 (14.3)	1 (5.9)	0 (0)	4 (5.7)
Multi-country	3 (14.3)	1 (5.9)	0 (0)	4 (5.7)
Singapore	0 (0)	3 (17.6)	1 (3.1)	4 (5.7)
China	3 (14.3)	0 (0)	0 (0)	3 (4.3)
Iran	2 (9.5)	0 (0)	0 (0)	2 (2.9)
France	0 (0)	0 (0)	2 (6.3)	2 (2.9)
Korea	0 (0)	0 (0)	2 (6.3)	2 (2.9)
Othersb	6 (28.6)	5 (29.4)	0 (0)	11 (15.7)
Type of study
Cross-sectional studies	21 (100)	15 (88.2)	29 (90.6)	65 (92.9)
Interventional studies	0 (0)	1 (5.9)	3 (9.4)	4 (5.7)
Qualitative studies	0 (0)	1 (5.9)	0 (0)	1 (1.4)
Sample size
0–499	7 (33.3)	9 (52.9)	21 (65.6)	37 (52.9)
500–1000	4 (19)	3 (17.6)	4 (12.5)	11 (15.7)
1000–5000	8 (38.1)	4 (23.5)	7 (21.9)	19 (27.1)
5001–10,000	2 (9.5)	1 (5.9)	0 (0)	3 (4.3)
Study population
Nonmedical personnel
General population	10 (47.6)	8 (47.1)	8 (25)	26 (37.1)
University students	0 (0)	0 (0)	4 (12.5)	4 (4.3)
Elderly	0 (0)	3 (17.6)	0 (0)	3 (2.9)
Rural villagers	0 (0)	1 (5.9)	0 (0)	1 (1.4)
Patients (dental)	0 (0)	1 (5.9)	1 (3.1)	2 (2.9)
Pilgrims	0 (0)	0 (0)	1 (3.1)	1 (1.4)
Medical personnel
Healthcare professionals	9 (42.9)	3 (17.6)	11 (34.4)	23 (32.9)
Medicine students	2 (9.5)	0 (0)	6 (18.8)	8 (11.4)
Mixed study populationsc	0 (0)	1 (5.9)	1 (3.1)	1 (1.4)
Rate of response in studies
Not specified	10 (47.6)	6 (35.3)	11 (34.4)	27 (38.6)
0–25%	2 (9.5)	0 (0)	1 (3.1)	4 (5.7)
25.1%–50%	0 (0)	1 (5.9)	4 (12.5)	5 (7.1)
50.1%–75%	3 (14.3)	6 (35.3)	4 (12.5)	12 (17.1)
75%–100%	6 (28.6)	4 (23.5)	12 (37.5)	22 (31.4)
Modality of assessment
Questionnaires
Online questionnaires	20 (95.2)	2 (11.8)	5 (15.6)	27 (38.6)
Physical questionnaires	0 (0)	3 (17.6)	21 (65.6)	24 (34.3)
Interviews
Face to face	0 (0)	6 (35.3)	6 (18.8)	12 (17.1)
Telephone	1 (4.8)	6 (35.3)	0 (0)	7 (10)
Language of questionnaire
English	16 (76.2)	8 (47.1)	9 (28.1)	33 (47.1)
Non-English	5 (23.8)	8 (47.1)	15 (46.9)	28 (40)
Multiple languagesd	0 (0)	1 (5.9)	8 (25)	9 (12.9)
Validated instruments
Yes	7 (33.3)	4 (23.5)	11 (34.4)	22 (31.4)
No	14 (66.7)	13 (76.5)	21 (65.6)	48 (68.6)
Number of health literacy questions
Not available	0 (0)	3 (17.6)	0 (0)	3 (4.3)
1–10	3 (14.3)	6 (35.3)	3 (9.4)	12 (17.1)
11–20	8 (38.1)	3 (17.6)	19 (59.4)	30 (42.9)
21–30	7 (33.3)	1 (5.9)	6 (18.8)	14 (20)
≥31	3 (14.3)	4 (23.5)	4 (12.5)	11 (15.7)
Components of health literacy addressed
Knowledge	20 (95.2)	14 (82.4)	31 (96.9)	65 (92.9)
Attitudes	17 (81)	11 (64.7)	21 (65.6)	49 (70)
Behaviours/practices	14 (66.7)	6 (35.3)	11 (34.4)	31 (44.3)

^aThere was no study from Australia and South America. ^bOther countries included Qatar, Pakistan, the UAE, Vietnam, Taiwan, Japan, Nigeria, Malaysia, the Netherlands, Italy and Jordan (n=1 for the listed countries). ^cA study evaluated both the elderly population and healthcare professionals. ^dLanguage combinations included English and Arabic; Japanese and English; Chinese, English and Malay. COVID-19: novel coronavirus disease 2019, MERS: Middle East respiratory syndrome, SARS: severe acute respiratory syndrome

Coronavirus disease 2019

A total of 21 (30.0%) studies examined health literacy related to COVID-19 [Table 1]. Majority of the studies were conducted in Asia (71.4%) and North America (14.3%). Most studies were conducted among the general population (n = 10, 47.6%). The primary mode of health literacy assessment across studies was via online questionnaires (n = 20, 95.2%). Aspects of health literacy that were assessed in the instruments included knowledge (n = 20, 95.2%), attitudes (n = 17, 81%) and practices (n = 14, 66.7%), of which only seven (33.3%) studies performed validation of their questionnaire. Most questionnaires (n = 8, 38.1%) contained 11–20 items. Pertaining to health literacy, the average percentage of correct answers among medical personnel ranged from 67.0% to 94.8% and low health literacy was found among 5.8%–43.5% of the participants [Supplemental Digital Appendix 2 ^{(905KB, pdf)} ]. The scores of the nonmedical populations ranged from 62.9% to 90.0%, and the proportion of participants with low health literacy was estimated at 16.1% [Supplemental Digital Appendix 2 ^{(905KB, pdf)} ]. The rate of low pandemic-related health literacy ranged from 6.8% to 43.5% in Asian countries compared to 16.1% in non-Asian countries. Among the low- and middle-income economies, the rates of pandemic-related health literacy ranged from 6.8% to 43.5%, while the rates in high-income economies were not reported.

Severe acute respiratory syndrome

Seventeen (24.2%) studies evaluated the level of health literacy related to SARS [Table 1]. Majority of the studies were performed in Asia (82.4%), followed by Europe (11.8%) and North America (5.9%). The most common groups of study participants included the general population (n = 8, 58.8%) and healthcare professionals (n = 3, 17.6%). The assessment of health literacy was conducted primarily via interviews (n = 12, 70.6%) and questionnaires (n = 5, 29.4%). Aspects of health literacy that were evaluated in the instruments were knowledge (n = 14, 94.1%), attitudes (n = 11, 64.7%) and behaviour/practices (n = 6, 82.4%). Majority of the instruments were not validated (n = 13, 76.5%). Regarding the number of health literacy questions, the majority (n = 6, 35.3%) had 1–10 questions, while four studies employed ≥31 questions. Pertaining to health literacy, the average correct answers from medical personnel ranged from 53.0% to 70.4% and participants with low health literacy were estimated at 28% [Supplemental Digital Appendix 2 ^{(905KB, pdf)} ]. For nonmedical personnel, the average correct answers ranged from 42.3% to 93.1% and proportion of participants with low health literacy ranged from 39.9% to 82.5% [Supplemental Digital Appendix 2 ^{(905KB, pdf)} ]. Within Asian countries, the rates of low pandemic health literacy ranged from 28% to 82.5%. The rates of pandemic-related health literacy in high-income countries ranged from 28% to 82.5%. The rates of low pandemic-related health literacy were not reported in non-Asian countries or in low- and moderate-income economies.

Middle East respiratory syndrome

The most number of studies examined health literacy related to MERS among the pandemics (n = 32, 45.7%) [Table 1]. The studies were mostly conducted in Asia (n = 30, 93.8%) and Europe (n = 2, 6.3%), with the majority from Saudi Arabia (n = 27, 84.4%). The most common group of participants recruited comprised healthcare professionals (n = 11, 34.4%) and medical students (n = 6, 18.8%). The assessment of health literacy was conducted predominantly via physical questionnaires (n = 21, 37.5%) and face-to-face interviews (n = 6, 18.8%). Aspects of health literacy that were most frequently evaluated were knowledge (n = 31, 96.9%), attitudes (n = 21, 65.6%) and behaviour/practices (n = 11, 34.4%). Only 34.4% of the instruments were validated. Pertaining to the number of questions used in the instruments, most studies had used 11–20 questions (n = 19, 59.4%) and 21–30 questions (n = 6, 18.8%). With regard to health literacy, the average correct answers from medical personnel ranged from 42.7% to 96.4% and the proportion of participants with low health literacy ranged from 4.3% to 57.9% [Supplemental Digital Appendix 2 ^{(905KB, pdf)} ]. For nonmedical personnel, the average correct answers ranged from 26.1% to 90.1% and the proportion of participants with low health literacy ranged from 4.0% to 59.2% [Supplemental Digital Appendix 2 ^{(905KB, pdf)} ]. The rate of low pandemic health literacy ranged from 4.3% to 49.3% in Asian countries compared to 4% in non-Asian countries. The rates of low pandemic health literacy were studied in only high-income countries and they ranged from 4% to 49.3%.

Themes identified from items used in health literacy questionnaires

Among the three themes, pandemic-related knowledge was most studied, followed by practices and attitudes [Supplemental Digital Appendices 4–6]. In the knowledge domain, symptoms,[13,14,16,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70] transmission[14,16,23,24,26,27,28,29,30,32,33,34,35,38,39,40,41,42,43,44,45,46,47,48,49,50,52,53,56,57,58,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79] and incubation period of the virus,[16,24,27,28,29,33,38,39,42,43,47,48,49,50,51,53,54,55,56,57,58,60,61,62,63,64,65,67,68,69,70,79] management and treatment options,[14,16,23,24,25,27,28,30,38,40,41,42,43,44,47,49,50,51,52,56,57,59,61,63,65,67,68,69,70,71,79,80] clinical outcomes associated with the infection,[13,16,24,25,26,27,28,30,35,38,39,41,49,51,52,53,56,57,60,62,64,65,66,67,68,70,75,76,77,79,80,81,82] high-risk populations for the infection,[16,24,27,28,30,38,40,41,42,49,50,56,57,58,59,60,64,66,68,69,73,79,80] availability of vaccine[16,30,38,40,41,43,44,45,49,53,56,57,59,61,62,63,64,66,69,71,75,76,77,80] and the role of hand hygiene[14,16,25,26,29,30,43,44,46,48,49,51,53,56,57,58,59,61,65,67,70,71,72,83,84] were the most studied for medical and nonmedical staff [Supplemental Digital Appendix 4]. For medical-related populations, specifically, knowledge about epidemiology[30,38,40,43,45,54,59,60,62,63,64,66,67,79,80] and knowledge about the diagnosis of infection[16,47,49,50,56,57,59,60,61,62,63,64,68,77] were frequently evaluated.

For attitudes about pandemics, worry/fear/helplessness about the pandemic,[13,14,23,29,32,34,50,52,53,61,62,64,66,69,73,77,78,79,82,84,85] confidence in governments’ ability to manage the pandemic[13,24,29,31,34,42,62,64,66,69,71,78,79,83] and perceived severity of infection as a public health problem[13,30,40,42,45,46,60,66,71,73] were the most commonly assessed [Supplemental Digital Appendix 5].

For practices in pandemics, behaviours related to mask utilisation,[14,16,24,27,29,31,33,34,36,39,41,49,60,62,64,66,71,74,81,83,85,86,87] hand hygiene,[14,16,29,33,34,36,39,41,42,47,60,61,62,64,66,71,74,78,86,87] personal hygiene[16,31,34,36,39,42,49,61,62,64,66,68,71,74,81,83,85,86,87] and information seeking[16,26,29,30,31,34,36,37,43,45,49,50,51,52,54,55,56,57,59,60,64,66,70,71,73,76,77,81,85,86,88] were most commonly studied [Supplemental Digital Appendix 6].

Figure 2 shows the proposed framework (PANDEMIC-related Health Literacy [PANDEMIC-HL]) for the items to be included in generic pandemic health literacy tools.

Figure 2.

Chart shows the proposed framework for items included in PANDEMIC-related Health Literacy instruments.

Determinants of health literacy

Across the five domains for health literacy-related factors, 34 factors were identified [Table 2]. Among these, sociodemographic, economic and health system–based domains were the most studied. Sociodemographic factors which were commonly associated with better health literacy included higher educational level,[24,27,28,34,35,37,38,40,41,43,44,46,73,74,75,76,77,78,81,82,83,89,90] increased age[24,27,31,38,41,44,49,51,64,66,73,75,76,79,85,86] and female gender.[13,16,24,27,34,35,39,41,42,45,46,61,63,73,75,79,81,82,85,86,90] Among the health system–based factors, increased experience in the healthcare system[49,57,64,77,78,90] and attendance in health education programmes[29,34,59,61,72,79] were associated with better health literacy. Among the medical and psychiatric/psychological factors, increased general health literacy[13,31] and increased anxiety about the spread of infection[29,34,81,85] were associated with better health literacy. Lastly, other factors associated with better health literacy included the use of traditional sources of information such as newspaper or television.[29,34,76]

Table 2.

Factors and their association with better health literacy (knowledge, attitudes and practices).

Factor	Number of supporting studies			Total number
	COVID-19	SARS	MERS
Sociodemographic factors
Education				26
Higher educational level	6[23,26,27,76,77,88]	7[33,34,36,72,73,80,82]	10[37,39,40,42,43,45,74,75,81,89]	23
Lower educational level	1[26]	2[72,80]	–	3
Age				26
Increased age	4[23,26,48,50]	4[30,72,84,85]	8[37,40,43,63,65,74,75,78]	16
Decreased age	1[48]	4[32,33,36,82]	5[37,41,42,44,81]	10
Gender				25
Female	3[13,23,26]	6[33,34,72,80,84,85]	12[16,38,40,41,44,45,60,62,74,78,81,89]	21
Male	1[46]	–	3[16,55,56]	4
Marital status (married vs. unmarried, divorced)	3[13,23,27]	2[34,85]	2[40,74]	7
Race (White vs. Black, Chinese and Malay vs. Others)	1[26]	3[33,36,84]	1[75]	5
Discipline of study (medical vs. non-medical)	1[50]	–	4[29,37,44,66]	5
Nationality [Finland vs. Dutch, Korean, Jordan vs. Saudi Arabian)	–	1[35]	4[41,58,79,81]	5
Pilgrims (vs. non-pilgrims)	–	–	2[39,79]	2
Type of residence (villa vs. flat, apartments with more rooms vs. fewer rooms)		2[34,36]	1[75]	3
Level of English proficiency	1[13]	–	–	1
Location of residence (Hubei vs. other parts of China)	1[23]	–	–	1
Employed (vs. unemployed)	4[13,23,27,88]	2[34,36]	2[42,74]	8
Healthcare workers (vs. non healthcare workers)	4[48,50,52,77]	–	3[43,63,78]	7
Income level				6
Higher income level	2[26,88]	1[34]	1[40]	4
Lower income level	2[26,27]	–	–	2
Type of employment (mental labour vs. unemployed, physical labour, students)	1[23]	–	–	1
Medical factors
Higher general health literacy	1[13]	1[30]	–	2
Self-reported health status (good to excellent vs. poor)	1[13]	–	–	1
Higher number of chronic conditions	1[13]	–	–	1
Increased health activation (an individual’s willingness to take on the role of managing their health and healthcare)	1[13]	–	–	1
Increased self-efficacy in performing preventive health practices	–	1[30]	–	1
Psychological/psychiatric factors
Increased anxiety related to spread of infection	1[28]	3[33,80,84]	–	4
Increased perceived susceptibility to being infected	–	1[30]	1[60]	2
Decreased superstition and fatalism	1[28]	–	–	1
Health systems-based factors
Years of experience in healthcare system				7
More years of experience in healthcare system	3[48,76,77]	–	3[56,63,89]	6
Fewer years of experience in healthcare system	1[46]	–	–	1
Attendance in health education programmes (public health prevention programmes, continuous medical education activities)	1[28]	2[33,71]	3[58,60,78]	6
Physicians’ specialty or place of practice				3
Non-emergency department (vs. emergency department)	1[46]	–	–	1
Private medical sector (vs. public medical sector)	–	–	1[89]	1
Specialist (vs. primary care physicians])	–	–	1[58]	1
Presence of infection control programmes in hospitals	–	–	1[78]	1
Other factors
Sources of information
Traditional media [TV, newspaper, radio sources] (vs. others)	1[28]	1[33]	1[75]	3
Social media (vs. others)	1[28]	–	–	1
Textbook and lectures (vs. others)	–	–	1[58]	1
Political or government-related factors
General confidence in government/authority				2
Higher general confidence in authority	–	1[33]	–	1
Lower general confidence in authority	1[28]	–	–	1
Political affiliation (democrats and independents vs. republicans)	1[26]	–	–	1

Clinical outcomes

Among the included studies, no studies evaluated clinical outcomes related to COVID-19, SARS or MERS.

DISCUSSION

This review provides a summary of the existing literature on health literacy regarding COVID-19, SARS and MERS, as well as the factors and clinical outcomes associated with poor health literacy. To our best knowledge, this is the first review to summarise the levels and assessment of pandemic-related health literacy in the COVID-19, SARS and MERS pandemics.

Overall, the level of health literacy related to COVID-19 and other pandemics was found to be suboptimal in both medical and nonmedical populations. Given the important role health literacy plays in stemming the spread of infection and mitigating the impacts of these pandemics, there is an urgent need for designing interventions to rapidly improve the pandemic-related health literacy of the population. An area that could be targeted includes enhancing the general population’s health literacy. Studies have shown that general health literacy plays an important role in increasing COVID-19 protective behaviours and awareness.[91] Higher general health literacy is also associated with lower psychological disease burden and better coping strategies and preventive behaviours against COVID-19.[92] In this review, general health literacy was not found to be evaluated in the included studies, and this serves as an important research gap for future researchers to address. Potential strategies that have demonstrated efficacy and which could be employed include use of technology-based health literacy intervention through mobile devices, interactive learning strategies such as peer support groups and art-based health interventions.[93]

With regard to the determinants of pandemic-related health literacy, higher education levels, older age, female gender and being employed were the most studied factors associated with higher pandemic-related health literacy. Our results generally concurred with the determinants of general health literacy based on current literature. Pertaining to the role of gender, females have been identified in multiple studies to have higher general health literacy levels compared to their male counterparts.[94,95] This difference may be related to the traditional roles that females play in caring for family members and children, which increase their need for and familiarity with navigating and interacting with healthcare information and systems.[96] Employment creates opportunities for individuals to access healthcare resources.[17] Likewise, education attainment plays an important role in health literacy through its influence on knowledge, skills and resource interpretation and utilisation.[10,97] Interestingly, while older age has been associated with poorer health literacy in the general population possibly due to ageing-related factors such as cognitive decline and physical impairments,[98] our review showed that older age was associated with better health literacy. This may be related to the greater number of pandemics an older person experiences in his/her lifetime, due to which the knowledge gained from previous pandemics may shape their ability to gather, synthesise and comprehend information related to ongoing pandemics.[10,99] Another potential reason for this finding could be related to increased selection bias among older participants compared to studies performed for general health literacy. While our review has highlighted multiple determinants of pandemic-related health literacy, more studies are required to understand the complex interplay between these factors and their impact on health literacy.

Currently, there is no gold standard instrument which evaluates pandemic-related health literacy. Given the need for validated and standardised tools to be created to facilitate the evaluation of pandemic-related health literacy, the PANDEMIC-HL framework was proposed to guide the selection of topics to be addressed in instruments. It was modelled after the psychosocial models of health behaviours, and encompasses key topics which were frequently evaluated in instruments across the three pandemics.[100] The framework comprises three thematic pillars related to health literacy, which are knowledge, attitude and practices. Pertaining to knowledge, it relates to the understanding of factual information related to pandemics, medicine, health and its sciences. Specifically, with regard to knowledge of medicine and health, the former refers to understanding of medical information related to the pandemic and treatment options, while the latter refers to health-related and preventive behaviours.[101] The second pillar ‘attitude’ relates a person’s perception on pandemics and ability to cope. The third pillar ‘practices’ refers to one’s ability to process and utilise information to guide health-related actions in the context of pandemics. This entails actions such as seeking health-related information and executing preventive behaviours. The bidirectional arrows in the framework highlight the cross-knitted relationship between each of these three key pillars and their interdependent relationships. It is hoped that the framework will serve as a foundation for facilitating the development of health literacy tools for future pandemics.

There were several research gaps identified in this review, which should be addressed in future studies.

Firstly, there were limited studies which evaluated pandemic-related health literacy in high-risk populations. Populations at an increased risk of poor clinical outcomes of infections, such as the elderly, immunocompromised patients, patients with human immunodeficiency virus or multiple comorbidities, form high-priority populations in whom the levels of pandemic health literacy should be assessed.[102,103] In the context of the current COVID-19 pandemic, our review found only one study which specifically evaluated the health literacy related to COVID-19 among these high-risk populations.[13] It is imperative that future research is undertaken to evaluate the health literacy among these patient populations for targeted interventions to be designed for patients if required.

Secondly, there were no studies which evaluated clinical outcomes associated with poor pandemic-related health literacy. Poor general health literacy has been linked to adverse clinical outcomes such as increased healthcare utilisation and morbidity.[104] In addition, people with low general health literacy are more likely to delay or forego medical treatment, compared to their counterparts with adequate health literacy.[105] While it is expected that people with poor pandemic-related health literacy may have poorer clinical outcomes, this remains a significant research gap that should be addressed in future studies.

The main strength of this review was that health literacy in previous coronavirus-related pandemics, such as SARS and MERS, was evaluated to provide a more comprehensive overview of pandemic-related health literacy. However, the findings from this review should also be interpreted with the following limitations. Firstly, while we adopted a reasonably comprehensive search strategy, potentially relevant articles may have been missed. Hand searching within the references of included articles was performed to minimise this omission of potentially relevant articles. Secondly, we were only able to include articles in the English language due to the language limitations of the authors. Thirdly, we were not able to perform meta-analyses for the overall level of pandemic-related health literacy and their determinants due to the heterogeneity in instruments. With the development of a standardised instrument for the assessment of health literacy related to pandemics, future studies should consider using meta-analyses to compare the level of health literacy across different populations. Lastly, the full questionnaires could not be accessed for 27 studies. While themes described in the main text of these articles were carefully extracted, we cannot rule out the omission of themes which were not described. Future health literacy studies should append their questionnaires to allow meaningful evaluation of the study results.

In conclusion, overall, the level of pandemic-related health literacy remains suboptimal among both medical and nonmedical populations. This is worrisome, given the critical role health literacy serves in reducing the spread of contagion and mitigating the effects of pandemics. There is an urgent need to develop up-to-date, validated and standardised questionnaires for the rapid assessment of pandemic-related health literacy. Important determinants associated with better levels of health literacy, such as older age, female gender, employment status and education level, were highlighted in this review. Healthcare administrators and policymakers need to be mindful of these determinants when formulating dissemination of critical pandemic-related information and interventions to improve the health literacy of the population. More studies are required to evaluate the clinical outcomes associated with pandemic-related health literacy.

Conflicts of interest

There are no conflicts of interest.

Supplemental digital content

Appendix 1 at http://links.lww.com/SGMJ/A175

Appendix 2 ^{(905KB, pdf)} at http://links.lww.com/SGMJ/A176

Appendix 3 at http://links.lww.com/SGMJ/A177

Appendix 4 at http://links.lww.com/SGMJ/A178

Appendix 5 at http://links.lww.com/SGMJ/A179

Appendix 6 at http://links.lww.com/SGMJ/A180

APPENDICES

Appendix 1. Details of search strategy

Major literature databases

1. Medline:

Search strategy: #1 AND (#2 OR #3 OR #4)

S/No	Key terms	Terms utilized
1	Health literacy	("Health Literacy"[Mesh] OR "Health Literacy"[tiab] OR "health knowledge"[tiab] OR "medical data interpretation"[tiab] OR "health competence"[tiab] OR "health attitude"[tiab]) OR (("Health"[Mesh] OR health[tiab] OR patient*[tiab]) AND (literacy[tiab] OR literate[Tiab] OR "reading skills" [tiab] OR "reading ability"[tiab] OR "reading level"[tiab] OR "writing level"[tiab] OR "writing ability"[tiab] OR "writing skills"[tiab] OR numeracy[tiab] OR analphabetism[tiab] OR comprehens*[tiab] OR motivat*[tiab] OR educat* OR knowledge OR attitude))
2	COVID-19	"COVID-19"[Supplementary Concept]" OR COVID-19[tiab] OR Covid19[tiab] OR Coronavirus disease 2019[tiab] OR "Novel coronavirus"[tiab] OR "wuhan virus"[tiab]
3	MERS	MERS[tiab] OR "Middle East Respiratory Syndrome"[tiab]
4	SARS	SARS[tiab] OR "Severe acute respiratory syndrome"[tiab]

2. Embase

Search strategy: #1 AND (#2 OR #3 OR #4)

S/No	Key terms	Terms utilized
1	Health literacy	("health literacy"/exp OR "health literacy" OR "health knowledge"/exp OR "health knowledge" OR "medical data interpretation" OR "health competence" OR "attitude to health"/exp OR "attitude to health" OR (("health" OR "health’/exp OR health OR patient*) AND ("literacy"/exp OR literacy OR literate OR "reading skills"/exp OR "reading skills" OR "reading ability"/exp OR "reading ability" OR "reading level" OR "writing level" OR "writing ability" OR "writing skills" OR "numeracy"/exp OR numeracy OR "analphabetism"/exp OR analphabetism OR comprehens* OR motivat* OR educat* OR "knowledge"/exp OR knowledge OR "attitude"/exp OR attitude)))
2	COVID-19	"covid 19"/exp OR "covid 19" OR covid19 OR "coronavirus disease 2019"/exp OR "coronavirus disease 2019" OR "novel coronavirus" OR "sars-cov-2" OR "2019-ncov" OR "wuhan virus"
3	MERS	mers OR "middle east respiratory syndrome"/exp OR "middle east respiratory syndrome"
4	SARS	"sars"/exp OR sars OR "severe acute respiratory syndrome"/exp OR "severe acute respiratory syndrome"

3. PsycInfo

Search strategy: #1 AND (#2 OR #3 OR #4)

S/No	Key terms	Terms utilized
1	Health literacy	(("Health Literacy" OR "health knowledge" OR "medical data interpretation" OR "health competence" OR "attitude to health") OR (("Health" OR health OR patient) AND (literacy OR literate OR "reading skills" OR "reading ability" OR "reading level" OR "writing level" OR "writing ability" OR "writing skills" OR numeracy OR analphabetism OR comprehension OR motivation OR education OR knowledge OR attitude)))
2	COVID-19	COVID-19 OR COVID19 OR "Coronavirus disease 2019" OR "Novel coronavirus" OR "SARS-CoV-2" OR "2019-nCOV" OR "Wuhan virus"
3	MERS	MERS OR "Middle East Respiratory Syndrome"
4	SARS	SARS OR "Severe acute respiratory syndrome"

4. CINAHL

Search strategy: #1 AND (#2 OR #3 OR #4)

S/No	Key terms	Terms utilized
1	Health literacy	(("Health Literacy" OR "health knowledge" OR "medical data interpretation" OR "health competence" OR "attitude to health") OR (("Health" OR health OR patient*) AND (literacy OR literate OR "reading skills" OR "reading ability" OR "reading level" OR "writing level" OR "writing ability" OR "writing skills" OR numeracy OR analphabetism OR comprehens* OR motivat* OR educat* OR knowledge OR attitude)))
2	COVID-19	COVID-19 OR COVID19 OR "Coronavirus disease 2019" OR "Novel coronavirus" OR "SARS-CoV-2" OR "2019-nCOV" OR "Wuhan virus"
3	MERS	MERS OR "Middle East Respiratory Syndrome"
4	SARS	SARS OR "Severe acute respiratory syndrome"

Preprint databases

arXiv

("Health Literacy" OR "health knowledge" OR "medical data interpretation" OR “health competence“ OR “health attitude”) AND (COVID-19 OR COVID19 OR “Coronavirus disease 2019” OR “Novel coronavirus” OR “Wuhan virus” OR “SARS-CoV-2” OR “2019-nCOV” OR “MERS” OR “SARS”)

bioRxiv

("Health Literacy" OR "health knowledge" OR "health competence" OR “health attitude”) AND (“COVID-19" OR “SARS” OR “MERS”) Social Science Research Network (SSRN)

("Health Literacy" OR "health knowledge" OR "medical data interpretation" OR "health competence" OR “health attitude”) AND (COVID-19 OR COVID19 OR “Coronavirus disease 2019” OR “Novel coronavirus” OR “Wuhan virus” OR “SARS-CoV-2” OR “2019-nCOV” OR “MERS” OR “SARS”)

medRxiv

("Health Literacy" OR "health knowledge" OR "health competence" OR “health attitude”) AND (“COVID-19" OR “SARS” OR “MERS”)

Appendix 3.

Assessment of risk of bias across studies

Authors (Year)	1. Was the research question or objective in this paper clearly stated?	2. Was the study population clearly specified and defined?	3. Was the participation rate of eligible persons at least 50%?	4. Were all the subjects selected or recruited from the same or similar populations (including the same time period)? Were inclusion and exclusion criteria for being in the study prespecified and applied uniformly to all participants?	5. Was a sample size justification, power description, or variance and effect estimates provided?	6. For the analyses in this paper, were the exposure(s) of interest measured prior to the outcome(s) being measured?	7. Was the time frame sufficient so that one could reasonably expect to see an association between exposure and outcome if it existed?	8. For exposures that can vary in amount or level, did the study examine different levels of the exposure as related to the outcome (e.g., categories of exposure, or exposure measured as continuous variable)?	9. Were the exposure measures (independent variables) clearly defined, valid, reliable, and implemented consistently across all study participants?	10. Was the exposure(s) assessed more than once over time?	11. Were the outcome measures (dependent variables) clearly defined, valid, reliable, and implemented consistently across all study participants?	12. Were the outcome assessors blinded to the exposure status of participants?	13. Was loss to follow-up after baseline 20% or less?	14. Were key potential confounding variables measured and adjusted statistically for their impact on the relationship between exposure(s) and outcome(s)?	Overall assessment of bias in each study
Moro et al. (2020)	Y	Y	N	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Kamate et al. (2020)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Wolf et al. (2020)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Taghrir et al. (2020)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Khader et al. (2020)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Shi et al. (2020)	Y	Y	N	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Zhong et al. (2020)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Roy et al. (2020)	Y	Y	N	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Geldsetzer (2020)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Zhou et al. (2020)	Y	Y	N	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
McFadden et al. (2020)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Saqlain et al. (2020)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Olapegba et al. (2020)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Clements (2020)	Y	Y	N	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Naser et al. (2020)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Lim et al. (2020)	Y	Y	N	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Gupta et al. (2020)	Y	Y	N	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Gudi et al (2020)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Hazreen et al. (2004)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Tang and Wong (2003)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Seng et al (2004)	Y	Y	N	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Vijaya et al. (2005)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Tse et al. (2003)	Y	Y	N	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Lau et al. (2005)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Chan et al. (2006)	Y	Y	N	Y	N	Y	Y	Y	Y	NA	Y	NA	Y	Y	Moderate
Lui et al. (2005)	Y	Y	N	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Vijaya et al. (2004)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
yip et al. (2005)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Bener et al. (2004)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Al-Mohaissen et al. (2017)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Baseer et al. (2016)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Almutairi et al. (2015)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Migault et al. (2019)	Y	Y	NS	Y	Y	Y	Y	NA	NA	N	Y	NA	Y	Y	Moderate
Elrggal et al. (2018)	Y	Y	NS	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Gautret et al. (2013)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Al-Mohrej et al. (2015)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Ashok et al. (2016)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Althomairy et al. (2018)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Khan et al. (2014)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Althobaity et al. (2017)	Y	Y	NS	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Gaffar et al. (2019)	Y	Y	N	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Al-Amri et al. (2019)	Y	Y	NS	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Alsahafi et al. (2016)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Bawazir et al. (2017)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Albarrak et al. (2019)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Yang et al. (2017)	Y	Y	N	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Kim et al. (2016)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Nour et al. (2017)	Y	Y	Y	Y	N	Y	Y	NA	NA	NA	Y	NA	Y	NA	Low
Al-Mohrej et al (2017)	Y	Y	N	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Nooh et al. (2020)	Y	Y	NS	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Kharma et al. (2015)	Y	Y	NS	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Hou et al. (2018)	Y	Y	NS	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Nour et al. (2015)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	Y	Low
Almutairi et al. (2016)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	Y	Low
Brug et al. (2004)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	Y	Low
Imai et al. (2005)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	Y	Low
Tice et al. (2006)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	Y	Low
Elbur et al. (2016)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Bhagavathula (2020)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Nemati et al (2020)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Giao et al (2020)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Vartti et al (2009)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
So et al (2004)	Y	Y	N	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Moderate
Tork and mersal (2018)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Deng et al (2006)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Asaad et al (2020)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Al-Hazmi et al. (2018)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Alkot et al. (2016)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Alqahtani et al. (2017)	Y	Y	Y	Y	Y	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low
Alshammari et al (2018)	Y	Y	Y	Y	N	NA	NA	NA	NA	NA	Y	NA	Y	NA	Low

Abbreviations: N - No; NA - Not applicable; Y - Yes;

Appendix 4.

Themes identified from knowledge-based questions from instruments

Themes		Number of studies (non-medical populations)				Number of studies (Medical related populations)				Total number
		COVID-19	SARS	MERS	Sub-total	COVID-19	SARS	MERS	Sub-total
1) Knowledge
General information
Vectors or source of virus e.g. animals, plants		3(14, 26, 56)	-	5(38, 41, 43, 45, 82)	8	3(49, 51, 52)	-	12(16, 38, 57-60, 62-66, 70)	15	23
Aetiology of infection e.g. viral, bacterial			3(33, 36, 81)	6(38, 39, 41, 43-45)	9	1(49)	1(55)	11(16, 30, 38, 56, 57, 61, 62, 64, 68, 70, 79)	13	22
Awareness of virus		2(29, 71)	4(31, 32, 36, 81)	9(40-42, 45, 75, 76, 80, 82, 87)	15	2(51, 77)	-	4(60, 63, 65, 66)	6	21
Epidemiology of infection e.g. prevalence		1(30)	-	5(38, 40, 43, 45, 80)	6	-	1(54)	9(38, 59, 60, 6264, 66, 67, 79)	10	16
Origin of virus (country / continent)		1(26)	-	3(38, 40, 41)	4	3(47, 49, 77)	-	3(38, 56, 61)	6	10
Virus’s family or structure		-	-	-	0	1(47)	-	1(63)	2	2
Transmission, infectivity and symptoms
Symptoms of infection		10(13, 14, 23-30)	7(31-37)	9(38-46)	26	8(23, 47-53)	2(54, 55)	19(16, 30, 38, 54, 56-70)	29	55
Transmission of virus		9(14, 23, 24, 2630, 71)	7(32-35, 72-74)	11(38-46, 75, 76)	27	9(23, 47-50, 52, 53, 77, 78)	-	18(16, 30, 38, 5658, 60-70, 79)	26	53
Incubation period of virus		4(24, 27-29)	1(33)	4(38, 39, 42, 43)	9	6(47-51, 53)	2(54, 55)	16(16, 38, 56-58, 60-65, 67-70, 79)	24	33
High risk populations for infection		4(24, 27, 28, 30)	1(73)	5(38, 40-42, 80)	10	2(49, 50)		13(16, 30, 38, 5660, 64, 66, 68, 69, 79)	15	25
Level and/or duration of infectivity of virus		1(14)	2(31, 35)	4(38-40, 43)	7	-	-	4(56, 58, 65, 70)	4	11
Infectivity of virus among asymptomatic patients		3(24, 27, 28)	-	1(75)	4	-	-	4(59, 60, 63, 65)	4	8
Organs affected by infection		-	-	3(40, 41, 43)	3	1(77)	-	-	1	4
Differences or similarities in symptoms compared to other viral infections e.g. influenza		1(28)	-	1(80)	2	-	-	2(58, 65)	2	4
Venues where virus can be contracted		1(29)	-	1(38)	2	-	-	1(38)	1	3
Diagnosis, treatment and outcomes
Clinical outcomes associated with infection e.g. recovery, mortality		6(13, 24-28)	2(35, 81)	7(38, 39, 41, 75, 76, 80, 82)	15	5(49, 51-53, 77)		14(16, 30, 38, 56, 57, 60, 62, 64-68, 70, 79)	19	34
Management principles and treatment options available for infection		6(14, 24, 25, 27, 28, 71)		7(38, 40-44, 80)	13	6(23, 47, 49-52)		14(16, 30, 38, 56, 57, 59, 61, 63, 65, 67-70, 79)	20	33
Availability or role of vaccine for prevention of infection		2(30, 71)		9(38, 40, 41, 43-45, 75, 76, 80)	11	3(49, 53, 77)		12(16, 30, 38, 56, 57, 59, 61-64, 66, 69)	15	26
Methods of diagnosis		-	-	-	0	4(47, 49, 50, 77)	-	10(16, 56, 57, 5964, 68)	14	14
Protection conferred by other vaccines e.g. influenza		2(25, 30)	-	-	2	2(49, 51)	-	2(62, 64)	4	6
Laboratory findings associated with infection		-	-	-	0	-	-	1(59)	1	1
Indications for testing for infection		-	-	-	0	-	-	1(60)	1	1
Precautions required during the pandemic
Role of hand hygiene in preventing spread of infection		6(14, 25, 26, 29, 71, 83)	1(72)	3(43, 44, 46)	10	4(48, 49, 51, 53)	1(84)	10(16, 30, 56-59, 61, 65, 67, 70)	15	25
General preventive measures for infection e.g. avoiding crowded places		5(13, 23, 24, 27, 71)	3(31, 32, 34)	4(38, 40, 44, 45)	12	4(23, 47, 48, 51)	1(84)	6(30, 38, 63, 67, 69, 79)	11	23
Role of wearing masks for preventing spread of infection		6(24, 25, 27-30)	4(37, 72, 73, 83)	3(44, 46, 82)	13	1(53)	1(84)	5(30, 61, 62, 64, 90)	7	20
Infection control precautions to be used in healthcare settings for suspected / confirmed cases		2(23, 29)	1(34)	1(38)	4	4(23, 48-50)	1(84)	8(16, 38, 59-62, 64, 68)	13	17
Role of personal hygiene e.g. covering mouth when coughing		3(29, 30, 71)	3(34, 72, 83)	2(43, 46)	8	1(51)	-	6(30, 58, 61, 65, 67, 70)	7	15
Isolation precautions and their effectiveness for suspected / confirmed patients		5(14, 24, 27, 28, 89)	-	1(42)	6	2(48, 78)	1(83)	6(58-60, 62, 67, 90)	9	15
Role of personal protective equipment		1(24)	1(73)	1(38)	3	4(47, 48, 77, 78)	2(54, 84)	4(56, 57, 59, 61)	10	13
Specific dietary considerations to avoid infection e.g. consumption of wild animals in COVID 19		6(13, 24, 27-29, 71)	-	1(38)	7	1(51)	-	1(38)	2	9
Role of social distancing measures and preventing mass gatherings e.g. closure of schools		6(25-30)	1(83)	-	7	-	-	1(30)	1	8
Measures to adopt when one is ill		1(23)	4(31, 34, 37, 85)	1(40)	6	1(23)	-	-	1	7
Role of avoiding infected or sick patients		1(30)	1(83)	2(46, 83)	4	1(51)	-	2(30, 58)	3	7
Measures to take after exposure to direct contact with a suspected case		4(24, 25, 27, 30)	-	1(80)	5	1(47)	-	1(62)	2	7
Role of regular cleaning or disinfecting surfaces		2(26, 71)	-	-	2	4(48, 51, 78, 83)	-	1(59)	5	7
Role of complementary alternative medicine for prevention of infection e.g. consumption of herbal soups, garlic		5(25, 26, 29, 30, 71)		1(45)	6				0	6
Precautions required post travel e.g. isolation, declaring travel history		1(30)	1(73)	1(40)	3	-	-	3(56, 57, 61)	3	6
Technique and equipment required for proper handwashing / hand sanitisation		1(89)	1(72)	-	2	1(51)	-	2(56, 57)	3	5
Definitions of terms used in precautionary measures e.g. "safe distance", "close contacts", " transient contacts"		2(71, 89)		1(42)	3			2(59, 90)	2	5
Necessity for children and young adults to take extra precautions against infection		3(24, 27, 28)	-	-	3	-	-	-	0	3
Role of nasal saline washes or mouthwash		2(25, 30)	1(73)	-	3	-	-	-	0	3
Role of not touching face, eye or nose		1(25)	-	1(46)	2	-	-	-	0	2
Role of minimizing travel to affected countries		-	2(34, 83)	-	2	-	-	-	0	2
Role of opening mail carefully		2(30, 71)	-	-	2	-	-	-	0	2
Role of avoiding animals or insects e.g. live animals, mosquitoes		1(29)	-	1(38)	2	-	-	-	0	2
Role of minimizing infection during meals e.g. use of serving spoons		-	1(72)	-	1	-	-	1(65)	1	2
Period of self-isolation required for close contacts with known patients		1(89)	-	-	1	-	-	-	0	1
Role of education in preventing spread		-	1(35)	-	1	-	-	-	0	1
Technique and type of face mask to use		1(89)	-	-	1	-	-	-	0	1
Role of healthy lifestyles e.g. exercise		1(71)	-	-	1	-	-	-	0	1
Role of other vaccine		1(71)	-	-	1	-	-	-	0	1
Types of personal protective equipment required for families of suspected / known patients		-	-	-	0	-	1(54)	-	1	1
Role of contact tracing		-	-	-	0	-	-	2(62, 64)	1	1
Policies and measures implemented by authorities or healthcare institution
Control measures implemented by government e.g. restriction of travel to China	1(29)		1(34)	2(38, 87)	4	-	-	2(62, 64)	2	6
Repercussions associated with non-compliance with measures implemented by government or authorise	1(29)		-	-	1	-	-	-	0	1
Control measures implemented by healthcare institutions	-		-	-	0	-	1(32)	-	1	1

Appendix 5.

Themes identified from questions related to pandemic attitudes across instruments

Themes	Number of studies (non-medical populations)				Number of studies (Medical related populations)				Total number
	COVID-19	SARS	MERS	Sub-total	COVID-19	SARS	MERS	Sub-total
Attitudes
Related to infection in general
Worry, fear, helplessness or anxiety about contracting infection	4(13, 14, 23, 29)	4(32, 34, 73, 85)	1(82)	10	6(23, 50, 52, 53, 77, 78)	2(32, 84)	6(61, 62, 64, 66, 69, 79)	14	24
Perceived likelihood of self or others contracting infection	3(13, 29, 71)	2(36, 74)	1(42)	6	-	-	3(53, 61, 83)	3	9
Perceived ability to protect oneself, family members and/or other people around.	2(29, 71)	1(31)	-	3	1(88)	-	1(62)	2	5
Perceived ability in understanding and protecting self and others against the disease outbreak	3(13, 29, 71)	-	-	2	2(77, 88)	-	-	2	4
Perceived level of self-preparedness for infection outbreak	2(13,29)	-	-	2	-	-	-	0	2
Perceived impact on daily life	1(13)			1			1(66)	1	2
Belief that infection is preventable	-	-	-	0	-	-	2(62, 64)	2	2
Belief that infection is treatable at home	-	-	-	0	-	-	2(62, 64)	2	2
Beliefs in superstitions, luck or fate	1(29)	-	-	1	-	-	-	0	1
Belief that outbreak will worsen	1(71)	-	-	1	-	-	-	0	1
Belief that discrimination against country of origin is reasonable	1(71)	-	-	1	-	-	-	0	1
Belief that infection is a biochemical weapon developed by foreign countries or terrorists	1(30)	-	-	1	-	-	-	0	1
Feelings of fatigue after outbreak	-	-	-	0	1(78)	-	-	1	1
Acceptance of risk	-	-	-	0	-	1(84)	-	1	1
Avoidance of patients (healthcare workers)	-	-	-	0	-	1(84)	-	1	1
Related to practices / precautions to minimize transmission of infection
Perceived effectiveness of hospital infection control program in preventing spread	-	-	1(45)	1	2(49, 53)	-	6(16, 56, 57, 68, 69, 79)	8	9
Perceived effectiveness of personal protective equipment within healthcare settings	-	-	1(45)	1	1(49)	-	6(16, 56, 57, 62, 64, 68)	7	8
Belief that all infected patients should be kept in isolation	1(14)	-	1(45)	2	2(49, 53)	-	4(16, 56, 57, 68)	6	8
Perceived need for intensive care for suspected cases	-	-	-	0	1(49)	-	5(16, 56, 57, 68, 69)	6	6
Perceived effectiveness of social distancing measure	2(14, 89)	-	2(39, 45)	4	-	-	-	0	4
Perceived safety of traveling during epidemic/pandemic	3(14, 29, 71)	-	1(39)	4	-	-	-	0	4
Perceived effectiveness of hand hygiene and good personal hygiene	2(14, 89)	-	1(45)	3	1(53)	-	-	1	4
Perceived likelihood of getting vaccination against infection, if available	-	-	-	0	1(53)	-	3(66, 69, 79)	4	4
Perceived role of health education in disease prevention	-	-	-	0	1(77)	-	3(30, 62, 64)	4	4
Likelihood of quarantining oneself in infection when symptomatic	1(14)	-	1(42)	2	-	-	-	0	2
Perceived effectiveness of avoiding infected persons	-	-	1(45)	1	-	1(84)	-	1	2
Importance of reporting suspected case to health authorities	-	-	-	0	-	-	2(62, 64)	2	2
Perceived effectiveness of avoiding handshaking behaviour	1(89)	-	-	1	-	-	-	0	1
Perceived effectiveness of wearing face mask	-	-	1(45)	1	-	-	-	0	1
Perceived safety of sharing food or eating with other people	1(89)	-		1	-	-	-	0	1
Perceived uptake of mask utilization within community	1(25)	-	-	1	-	-	-	0	1
Likelihood of adhering to measures implemented by government or authorities	1(83)	-	-	1	-	-	-	0	1
Perceived level of knowledge on what to do if infected	1(29)	-	-	1	-	-	-	1	1
Perceived likelihood of removing child from school	-	-	1(42)	1	-	-	-	0	1
Avoiding specific dietary intake due to infection (e.g. consumption of non-vegetarian diet)	-	-	-	0	1(77)	-	-	0	1
Related to healthcare institutions, media, authorities government and universities
Confidence/satisfaction in government or authorities’ ability to manage and control of disease outbreak	4(13, 24, 29, 71)	3(31, 34, 83)	1(42)	8	1(78)		5(62, 64, 66, 69, 79)	6	14
Confidence or adequacy in information provided by media, government, authorities or schools about epidemic / pandemic	3(29, 30, 71)	2(31, 85)	1(45)	6			4(66, 67, 69, 79)	4	10
Perceived need for healthcare workers to be keep up-to-date about pandemic	-	-	1(45)	1	1(49)	-	5(16, 56, 57, 69, 79)	6	7
Belief that related information about pandemic should be disseminated to healthcare workers and public			1(45)	1	1(49)		4(16, 56, 57, 68)	5	6
Perceived level of understanding on measures adopted by government or authorities and their effectiveness in controlling spread of infection	1(29)	1(31)		2		1(84)	2(69, 79)	3	5
Belief that government should implement additional measures if cases increases e.g. closure of schools or reduce number of arrivals to Hajj			1(39)	1			2(62, 64)	2	3
Confidence in doctors in accurate diagnosis of infection	-	1(74)	-	1	-	-	-	0	1
Attitudes towards disclosure of exposure to infection by patients	-	-	-	0	1(78)	-	-	1	1
Impact of pandemic
Perceived severity of infection as a public health threat	2(13, 71)	1(73)	4(40, 42, 45, 46)	7	-	-	3(30, 60, 66)	3	10
Perceived impact of infection on self and/or community	1(71)	2(34, 74)	1(42)	4	-	-	1(62)	1	5
Perceived severe impact of infection on economy	-	1(34)	-	1	-	-	2(62, 64)	2	3
Perceived risk of job change	-	-	-	0	-	1(84)	-	1	1

Appendix 6.

Themes identified from questions related to pandemic practices across instruments

Themes	Number of studies (non-medical populations)				Number of studies (Medical related populations)				Total number
	COVID-19	SARS	MERS	Sub-total	COVID-19	SARS	MERS	Sub-total
3) Practices
To minimize transmission of infection in the community
Increased face mask usage in healthcare settings, travel, in public settings or unwell	5(14, 24, 27, 29, 71)	9(31, 33, 34, 36, 74, 81, 83, 85, 86)	3(39, 41, 87)	17	1(49)	-	5(16, 60, 62, 64, 66)	6	23
Frequency of hand-washing / hand hygiene practices	3(14, 29, 71)	5(33, 34, 36, 74, 86)	4(39, 41, 42, 87)	12	2(47, 78)	-	6(16, 60-62, 64, 66)	8	20
Increased practice of personal hygiene e.g. covering mouth when coughing	1(71)	8(31, 34, 36, 74, 81, 83, 85, 86)	3(39, 42, 87)	12	1(49)	-	6(16, 61, 62, 64, 66, 68)	7	19
Take general preventive measures against infection e.g. minimize going to crowded places, regular temperature taking, minimizing travelling out of house	5(14, 24, 27, 29, 71)	5(33, 36, 81, 83, 85)	4(41, 42, 82, 83)	14	2(47, 77)		2(61, 66)	4	18
Adopting healthy lifestyle e.g. exercise, adequate sleep	1(71)	7(31, 33, 34, 36, 81, 85, 86)	1(42)	9	-	-	3(62, 64, 68)	3	12
Avoidance or cancellation of travel to affected countries	2(29, 71)	2(81, 83)	2(39, 87)	6	-	-	1(61)	1	7
Seeking medical attention if unwell	-	6(34, 36, 37, 73, 85, 86)	-	6	-	-	-	0	6
Avoid food sharing, use of serving towels	1(89)	4(33, 72, 74, 83)	-	5	-	-	1(66)	1	6
Avoid visiting healthcare institution due to fear of contracting and spreading infection	1(29)	1(73)	2(41, 42)	4	1(50)	-	1(30)	2	6
Reduced public transportation use	1(29)	2(36, 81)	1(42)	4	1(47)	-	1(61)	2	6
Increased intake of complementary and alternative medicine e.g. vitamins, herbal supplements	2(29, 71)	3(33, 36, 81)	-	5	-	-	-	0	5
Made changes to daily planned activities e.g. meetings, events	2(13, 29)	1(34)	-	3	1(47)	-	1(61)	2	5
Took time off from work or school	1(29)	2(36, 81)	1(39)	4	-	-	-	0	4
Increased procurement of groceries	3(14, 27, 29)	-	-	3	-	-	-	0	3
Avoidance of contact with infected persons	1(29)	1(83)	1(87)	3	-	-	-	0	3
Comply with physicians or authorities instructions e.g. isolation precautions	-	2(34, 86)	1(83)	3	-	-	-	0	3
Avoid hand shaking	-	2(36, 81)	-	2	-	-	-	0	2
Ensuring adequate ventilation	-	1(31, 33)	-	2	-	-	-	0	2
Increased vaccination practices e.g. influenza	1(29)	1(33)	-	2	-	-	-	0	2
Self-quarantine from contact with family (for medical staff)	-	-	-	0	1(78)	-	-	1	1
Remove children from school to minimize contact with other children	1(29)	-	-	1	-	-	-	0	1
Increased water intake	1(29)	-	-	1	-	-	-	0	1
Increased antibiotics use	1(29)	-	-	1	-	-	-	0	1
Increased time and money spent on health	-	1(86)	-	1	-	-	-	0	1
Avoidance of risk behaviours e.g. unsafe sexual behaviours	-	1(86)	-	1	-	-	-	0	1
Adopt dietary changes e.g. reduce meat consumption	1(71)	-	-	1	-	-	-	0	1
Practices to minimize transmission of infection within healthcare settings
Safe handling of patients’ belongings	-	-	-	0	-	-	5(16, 56, 62, 64, 68)	5	5
Completion of infection specific training programs	-	-	-	0	2(78, 88)	1(55)	1(67)	4	4
Adopting use and safe removal of personal protective equipment after use	-	-	-	0	1(78)	-	1(16)	2	2
Increased cleaning and disinfection of items touched with hands e.g. door handles	1(29)	-	-	1	1(47)	-	-	1	2
Inclusion of travel history in recording patients’ history	-	-	-	0	1(77)	-	-	1	1
Education of self or others
Information seeking behaviour on virus and sources of information	4(26, 29, 30, 71)	8(31, 34, 36, 37, 73, 81, 85, 86)	3(43, 45, 76)	15	6(49-52, 77, 88)	2(54, 55)	9(16, 30, 56, 57, 59, 60, 64, 66, 70)	17	32
Discussion of preventive measures with friends or family	1(29)	-	-	1	2(47, 77)	-	4(61, 62, 64, 68)	6	7
Education of patients about infection e.g. signs and symptoms	-	-	-	0	2(49, 77)	-	3(61, 62, 64)	4	4

Funding Statement

Nil.