Anxiety Linked to COVID-19: Comparison
Please note this is a comparison between Version 2 by Jessie Wu and Version 1 by Hafsah Saeed.

The COVID-19 pandemic has incited a rise in anxiety, with uncertainty regarding the specific impacts and risk factors across multiple populations. A qualitative systematic research was conducted to investigate the prevalence and associations of anxiety in different sample populations in relation to the COVID-19 pandemic. 

  • anxiety
  • COVID-19
  • mental health

1. Introduction

Infectious disease outbreaks have plagued human history for millennia, with an occurrence not unknown to man, the effects of these outbreaks have eluded many. With the complexities of society, there are a plethora of ways these events may cause mental turmoil. As defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), anxiety is a state of excessive fear that translates to behavioural disturbances [1]. Anxiety has been linked to increased ulcers, back issues, migraines, and asthma [2]. In extreme cases, it is an independent risk factor for heart disease [3]. Perpetuated by stressful environments, anxiety threatens wellbeing when worry and fear regarding real or perceived threats hijacks an individual’s ability to regulate these emotions. Infectious disease outbreaks often evolve into epidemics or pandemics, which bring about financial instability, quarantine and lockdowns, social isolation, and complete disturbance of the norm. It is in this state of pandemonium that mental health deterioration may occur.
Officially declared by the World Health Organisation (WHO) as a pandemic in March 2020 [4], COVID-19 has transformed the way the world functions and triggered an altered perception of the effects and consequences of infectious disease. Originating in Wuhan, China, COVID-19 has spread rapidly worldwide, with 4,574,089 globally reported deaths as of September 2021 [4]. An epidemiological measurement called the basic reproduction number, or R0, is the average number of secondary cases that are derived from a single primary infection, with any number over one causing exponential infection growth [5]. With an average R0 of 3.38, COVID-19 is highly transmissible [6]. This transmissibility has resulted in astonishing rates of infection and has placed a massive demand on hospital resources, challenging even the most established healthcare systems [7]. The physical manifestations of COVID-19 are apparent in the overburdened hospitals and long-lasting adverse effects of the disease. The scale of infection has been linked to psychological distress, implying something sinister may be emerging, a mental health crisis [8].
Past infectious disease outbreaks, such as the severe acute respiratory syndrome (SARS), swine flu (H1N1), and Ebola, have, in each case, demonstrated an increased prevalence of anxiety [9,10][9][10]. In the last two years, similar findings have been widely published regarding the COVID-19 pandemic [11]. A delineation between the COVID-19 pandemic and past infectious disease outbreaks are apparent through the unprecedented implementation of lockdowns, social isolation, and quarantines effecting the global populace. The Australian Bureau of Statistics (ABS) reported that the incidence of anxiety had doubled in 2020 compared to previous years [12]. A longitudinal study conducted in the United Kingdom (UK) stipulated that one month into lockdown orders, mental distress levels well exceeded the predicted trajectories of previous years [13].
As the COVID-19 pandemic is ongoing, the long-term mental health effects are not yet known [14]. During the SARS outbreak, a range of literature concluded that the mental health consequences of SARS were not entirely immediate and lagged in comparison to the infectious outbreak [9,15,16,17][9][15][16][17]. Psychological distress among SARS survivors displayed a 64% prevalence one year after the initial outbreak [9]. These results may be indicative of the effects we can expect from the current pandemic.
Studies exploring different population groups affected by COVID-19 have identified some common risk factors associated with a higher likelihood of developing anxiety symptoms, including: younger age groups, being female, having pre-existing mental health issues, and lower socioeconomic status (SES) populations [18,19][18][19]. The effects of COVID-19 on healthcare workers, the general population, and other vulnerable groups such as pregnant women have been well documented. Reviews conducted on the comparison between health care workers and the general population have been extensive. However, no review comparing multiple different groups, namely, that of healthcare workers, the general population, university students, and other vulnerable groups (pregnant women, the elderly, teachers, and police) currently exists.

2. Study Characteristics

The sample size assessed in the research, derived from the total sample size of each study included in the research, was n = 755,180 with approximately n = 432,944 females, n = 280,089 males, and n = 42,147 participants that identified as other or did not report their sex. The age range of individuals within the included papers was 18–100 years and encompassed participants from 32 countries, with the highest number of studies originating from China (26/87 studies). The majority of studies were cross-sectional in design (70 studies), followed by longitudinal studies (13 studies), cohort studies (3 studies), and one case-control. All studies utilised validated psychometric measures, with the most common measure being the generalised anxiety disorder (GAD) 7 item scale [24][20] (43 studies). Other psychometric measures utilised included the Depression Anxiety Stress Scale (DASS) [20][21], the Patient Health Questionnaire (PHQ) [25][22], and the State-Trait Anxiety Inventory (STAI) [26][23]. Key differences in these measures are the extent to which anxiety is assessed, with measures such as the GAD and STAI focusing on generalised anxiety disorder only and state-related anxiety, respectively. Measures such as the DASS and PHQ evaluate other mental health symptoms relating to stress and depression, and anxiety symptoms. A summary of the study characteristics and anxiety prevalence is detailed in Table 1.
Table 1. Characteristics and anxiety prevalence of the selected studies.
Reference Study Design Population Type Country Sample Size Assessment Tools Prevalence of Anxiety (%)
Aharon et al., 2020 [27][24] Cross-sectional General population Israel and Italy 1015 PHQ-4, SF-8 50.2% of Italian and 42.2% of Israelis
Albagmi et al., 2012 [28][25] Cross-sectional General population Saudi Arabia 3017 GAD-7 80% (mild), 11.4% (moderate), 8.2% (severe)
Alshekaili et al., 2020 [29][26] Cross-sectional Healthcare workers Oman 1139 DASS-21 34.1%
Antonijevic et al., 2020 [30][27] Cross-sectional Healthcare workers Serbia 1678 GAD-7 43.31% (minimal), 30.9% (mild), 12.99% (moderate),12.8% (severe).
Ausin et al., 2020 [31][28] longitudinal General population Spain 1041 GAD-2 N/A
Batterham et al., 2021 [32][29] longitudinal General population Australia 1296 GAD-7, PHQ-9 77%
Bendau et al., 2020 [11] Longitudinal General population Germany 2376 GAD-2, PHQ-4 N/A
Budimir et al., 2021 [33][30] Cross-sectional General population Austria and UK 2011 GAD-7 18.9% UK and 6% Austria
Cai et al., 2020 [34][31] case-control Healthcare workers China 2346 BAI Frontline 15.7%, non-frontline 7.4%
Canet-Juric et al., 2020 [35][32] longitudinal General population Argentina 6057 STAI N/A
Cao et al., 2020 [36][33] Cluster Sampling University Students China 7143 GAD-7 Mild (21.3%), moderate (2.7%), severe (0.9%)
Chen et al., 2021 [37][34] Cross-sectional General population (quarantined) China 1837 STAI 16.3%
Chew et al., 2020 [38][35] Cross-sectional Healthcare workers India, Indonesia, Singapore, Malaysia and Vietnam 1146 DASS-21 India (0.8%), Singapore (3.6%), Vietnam (6.7%), Indonesia (6.8%) and Malaysia (14.9%)
Dawel et al., 2020 [39][36] longitudinal General population Australia 1296 GAD-7, PHQ-9, WHO-5 N/A
Denning et al., 2021 [40][37] Cross-sectional Healthcare workers UK, Poland and Singapore 3537 HADS 20%
Di Blasi et al., 2021 [41][38] longitudinal General population Italy 1129 DASS-21 N/A
Di Giuseppe et al., 2020 [42][39] Cross-sectional General population Italy 5683 SCL-90 51.1%
Di Mattei et al., 2021 [43][40] Baseline assessment Healthcare workers Italy 1055 DASS-21 69.4%
Fiorillo et al., 2020 [44][41] longitudinal General population Italy 20,720 DASS-21, GHQ Moderate (16.7%) and severe or extremely severe (17.6%)
Fisher et al., 2020 [45][42] Cross-sectional General Population Australia 13,829 GAD-7, PHQ-9 21%
Fu et al., 2020 [46][43] Cross-sectional General population China 1242 GAD-7, PHQ-9 27.6%
Fu et al., 2021 [47][44] Cross-sectional University students China 89,588 GAD-7 41.1%
Gainer et al., 2021 [48][45] Cross-sectional Healthcare workers US 1724 GAD-7, PHQ-9 36.5%
Garcia-Fernandez et al., 2020 [49][46] Cross-sectional Elderly population Spain 1639 HARS N/A
Garcia-Fernandez et al., 2020 [50][47] Cross-sectional General population Spain 1635 HARS N/A
Giardino et al., 2020 [51][48] Cross-sectional Healthcare workers Argentina 1059 DASS-18 76.5%
Gundogmus et al., 2021 [52][49] longitudinal Healthcare Workers Turkey 2460 DASS-21 29.6%
Hacimusalar et al., 2020 [53][50] Cross-sectional Healthcare, non-healthcare Turkey 2156 STAI 89.5%
Halperin et al., 2021 [54][51] Cross-sectional University students US 1428 GAD-7, PHQ-9 30.6%
Hammarberg et al., 2020 [55][52] Cross-sectional General population Australia 13,762 GAD-7 21.8% females, 14.2% males
Hassannia et al., 2021 [56][53] Cross-sectional Healthcare workers and general population Iran 2045 HADS 65.6%
He et al., 2021 [57][54] Cross-sectional Healthcare workers China 1971 GAD-7 29.3%
Hennein et al., 2021 [58][55] Cross-sectional Healthcare workers US 1092 GAD-7 15.6%
Huang et al., 2021 [59][56] Cross-sectional Healthcare workers Singapore 1638 GAD-7 12.5%
Islaml et al., 2020 [60][57] Cross-sectional University students Bangladesh 3122 DASS-21 Mild anxiety (71.5%), moderate (63.6%), severe (40.3%) and very severe (27.5%).
Jacques-Avino et al., 2020 [61][58] Cross-sectional General population Spain 7053 GAD-7 31.2% females, 17.7% males
Jia et al., 2020 [62][59] Cross-sectional General population UK 3097 GAD-7 57% (26% moderate to severe anxiety)
Jiang et al., 2020 [63][60] Cross-sectional General population China 60,199 SAI Mild (33.21%), moderate (41.27%) and severe (22.99%).
Johnson et al., 2021 [64][61] longitudinal Parents Norway 2868 GAD-7 N/A
Kantor and Kantor, 2020 [65][62] Cross-sectional General population US 1005 GAD-7 52.1% mild, 26.8% anxiety disorder
Karaivazoglou et al., 2021 [66][63] Cross-sectional General population Greece 1443 HADS 20%
Khubchandani et al. 2021 [67][64] Cross-sectional General population US 1978 GAD-2, PHQ-4 42%
Kim et al., 2021 [68][65] longitudinal University Students US 8613 GAD No significant changes were found in the rates of anxiety from before the pandemic.
Lai et al., 2020 [69][66] Cross-sectional Healthcare workers China 1257 GAD-7 44.6%
Lei et al., 2020 [70][67] Cross-sectional General population China 1593 SAS 8.3%
Li et al., 2020 [71][68] Cross-sectional Teachers China 88,611 GAD-7 13.67%
Li et al., 2021 [72][69] Cross-sectional General population China 1201 DASS-21 34.2%
Liu et al., 2021 [73][70] Cross-sectional Healthcare workers China 1090 GAD-7 13.3%
Liu et al., 2020 [74][71] Cross-sectional Healthcare workers (paediatric) China 2031 DASS-21 18.3%
Lu et al., 2020a [75][72] Cross-sectional General population and frontline workers China 1417 GAD-7 52.1% of the general public and 56% of frontline workers
Lu et al., 2020b [76][73] Cross-sectional Healthcare workers China 2299 HAMA 22.6% of medical staff showed mild to moderate anxiety and 2.9% were severe
Luceno-Moreno et al., 2020 [77][74] Cross-sectional Healthcare workers Spain 1422 HADS 58.6% healthcare workers presented with an anxiety disorder.
Mattila et al., 2020 [78][75] Cross-sectional Healthcare workers Finland 1995 GAD-7 30% mild anxiety, 10% moderate and 5% severe anxiety.
Meesala et al., 2021 [79][76] Cross-sectional General population India 1346 CAS-7 N/A
Mosheva et al., 2020 [80][77] Cross-sectional Healthcare workers Israel 1106 PROMIS 52.8%
Ngoc Cong Duong et al., 2020 [81][78] Cross-sectional General population Vietnam 1385 DASS-21 14.1%
Nkire et al., 2021 [82][79] Cross-sectional General population Canada 6041 GAD-7 46.7%
Odriozola-Gonzalez et al., 2020 [83][80] Cross-sectional University students and workers. Spain 2530 DASS-21, IES 21.34%
Ozamiz-Etxebarria et al., 2021 [84][81] Cross-sectional Teachers Spain 1633 DASS-21 49.5% (8.1% extreme severe and 7.6% severe)
Ozamiz-Etxebarria et al., 2020 [85][82] longitudinal General population Spain 1933 DASS-21 26.9%
Pandey et al., 2020 [86][83] Cross-sectional General population India 1395 DASS-21 Anxiety prevalence was 22.4% in the second week and 26.6% in the third week of lockdowns
Passavanti et al., 2021 [87][84] Cross-sectional General population Australia, Iran, China, Ecuador, Italy, Norway and the US 1612 DASS-21 44.7% (5.2% mild, 17.4% moderate, 5.8% severe and 16.3% extremely severe).
Pieh et al., 2021 [88][85] Cross-sectional General population UK 1006 GAD-7 39%
Peih et al., 2020 [89][86] Cross-sectional General population Austria 1005 GAD-7 19%
Planchuelo-Gomez et al., 2020 [90][87] longitudinal General population Spain 4724 DASS-21 49.66%
Robb et al., 2020 [91][88] Cross-sectional Elderly population UK 7127 HADS N/A
Rossi et al., 2020 [92][89] Cross-sectional Healthcare workers and general population Italy 24,050 GAD-7 21.25% in the general population, 18.05% in second line healthcare workers and 20.55% in frontline workers.
Ruengorn et al., 2020 [93][90] Cross-sectional General population Thailand 2303 GAD-7 56.9%
Serafim et al., 2021 [94][91] Cross-sectional General population Brazil 3000 DASS-21 39.7%
Shen et al., 2020 [95][92] Cross-sectional Healthcare Workers China 1637 SAS 10.02%
Sinawi et al., 2021 [96][93] Cross-sectional General Population Oman 1538 GAD-7 22%
Solomou et al., 2020 [97][94] Cohort study General population Cyprus 1642 GAD-7 41% mild, 23.1% moderate-severe
Sun et al., 2021 [98][95] Cross-sectional University Students China 1912 GAD-7 34.73%
Tang et al., 2020 [99][96] Cross-sectional General population China 1389 GAD-7 70.78%
Van der Velden et al., 2020 [100][97] Longitudinal General population Holland 3983 GAD-7 No significant anxiety found
Wang et al., 2021a [101][98] Case-control General population China 1674 ADS 27% in quarantined, 11.2% in general population
Wang et al., 2021b [102][99] Cross-sectional Healthcare workers China 1063 GAD-7 48.7% in patients, 25.7% general population, 13.3% healthcare
Wang et al., 2020 [103][100] Cross-sectional General, covid and health China 49,015 DASS-21 10.02%
Wanigasooriya et al., 2021 [104][101] Cross-sectional Healthcare workers UK 2638 PHQ-4 34.31%
Warren et al., 2021 [105][102] Cross-sectional General population United States 5023 PHQ-4 14.4%
Wathelet et al., 2020 [106][103] Cross-sectional University Students France 69,054 STAI 27.47%
Wu et al., 2020 [107][104] Cross-sectional General population China 24,789 STAI 51.6%
Yuan et al., 2020 [108][105] Cross-sectional Police China 3517 HADS 8.79%
Zhang et al., 2020a [109][106] Cross-sectional Healthcare workers China 2143 GAD-7 14.23%
Zhang et al., 2020b [110][107] Cross-sectional General population China 123,768 GAD-7 3.4%
Zhou et al., 2020 [111][108] Cross-sectional Healthcare workers China 1705 SAS 45.4%
Zilver et al., 2021 [112][109] Cohort study Pregnant women Holland 1466 GAD-7 19.5%
Key: GAD-7, Generalised Anxiety Disorder—7 Item Scale; DASS-21, Depression Anxiety Stress Scale—21 Item; PHQ-4, Patient Health Questionnaire—4 Item; SAS, Self-Rating Anxiety Scale; HARS. Hamilton Anxiety Rating Scale; SCL-90, Symptom Checklist—90 Item; CAS, Coronavirus Anxiety Scale; PROMIS, Patient-Reported Outcomes Measurement Information System; STAI, State-Trait Anxiety Inventory; HADS, Hospital Anxiety and Depression Scale.

3. The General Population Group

The general population was the most common group studied amongst the studies included in the research, with 47 papers focusing on anxiety assessment. The 47 papers comprised of a sample size of n = 421,598 participants, with n = 208,675 females, n = 178,187 males, and n = 34,736 other or sex not reported. The prevalence of anxiety ranged from 3.4–97.47% across the 47 study populations. The overall pooled anxiety prevalence was 34%, although eight studies did not directly report the prevalence of anxiety in their populations.
Amongst the general population, three studies [27,39,89][24][36][86] demonstrated that the prevalence of anxiety during the COVID-19 pandemic had risen when compared to data from preceding years; that is, in 2017 anxiety rates were 6%, but after the pandemic hit, this figure inflated to 19% [89][86]. Conversely, Velden (2020) reported no significant increase in the prevalence of anxiety in a before and after study comparing mental health rates in 2019 and 2020 [100][97]. However, the authors did note that despite an absence of an increase in anxiety, the risk factors predisposing participants to mental distress had changed since the onset of the pandemic, leaving students, job seekers, those with children, and those who housekeep more at risk in 2020 compared to the previous year.
Geographical locations that were identified as COVID-19 epicentres had higher instances of anxiety compared to non-epicentre areas [27,28,35,42,72,81,110][24][25][32][39][69][78][107]. Moreover, COVID-19 prevalent areas that exemplified elevated testing rates reported decreased anxiety [99][96]. Those with increased contact with COVID-19 infected individuals exhibited stronger associations with anxiety [45[42][84][91],87,94], especially if the individual was exposed to COVID-19 in a working environment such as healthcare [56,67][53][64]. Populations infected with COVID-19 expressed more anxiety than those who were not infected [44,56,61,102][41][53][58][99]. Job loss or financial hardship due to COVID-19 was often a predictor or factor for worse anxiety [39,93][36][90].
Quarantine and lockdown orders proved detrimental to mental health, as demonstrated in ten studies [27[24][34][39][42][79][82][83][96][98],37,42,45,82,85,86,99,101], with increased loneliness and isolation being the cause of significant increases in anxiety. In an Australian longitudinal study [32][29], there was a 23% increase in anxiety over a 12-week restriction period. Quarantining alone resulted in lower anxiety than people isolating with elderly dependents [35][32]. Three studies concluded that anxiety levels in populations decreased when rules were eased or when participants were exempted from participating in quarantines [11,35,75][11][32][72].
Certain demographic groups were identified as having a higher prevalence of anxiety or being more at risk of developing adverse mental health issues. Twenty-two studies found that females consistently had higher levels of anxiety than males [11,28,31,32,33,35,39,41,62,63,65,75,79,82,86,88,92,94,96,102,105,110][11][25][28][29][30][32][36][38][59][60][62][72][76][79][83][85][89][91][93][99][102][107]. However, two studies found that males were more anxious when living with dependents under 18 [50,61][47][58] and that younger males had higher instances of anxiety [56][53]. One study reported that males had higher rates of anxiety than females overall [107][104]. Two studies [82][79] and [101][98] did not delineate any significant differences between the sexes. Five studies reported that lower socioeconomic status was representative of greater anxiety [37,45,67,70,101][34][42][64][67][98]. Prior mental illness was also a contributing factor for worse mental health after COVID-19 [39,44,63,65,97][36][41][60][62][94]. Younger age groups displayed more anxiety than older age groups in sixteen studies [28,32,37,39,42,45,61,62,85,86,89,94,97,101,102][25][29][34][36][39][42][58][59][82][83][86][91][94][98][99].
Contrastingly, four studies identified an opposite trend, with elderly and older populations experiencing more anxiety than younger groups [46,79,82,90][43][76][79][87]. Six studies identified having a higher education being associated with worse anxiety [33,37,47,66[30][34][44][63][64][98],67,101], while two studies identified that lower education equated to increased anxiety [86,97][83][94]. Living alone or remotely and being unemployed were influences on increased anxiety [45,65,89,97][42][62][86][94]. Conversely, Fu and colleagues (2020) indicated that living in a city may be predictive of worse mental health [46][43]. Two studies reported no difference in anxiety levels between different demographics, including sex, age, education, or socioeconomic status [87,92][84][89].

4. Healthcare Worker Group

Healthcare workers constituted the subject of 25 of the 87 studies included in this research, with a total sample size of 43,387 participants. This sample consisted of n = 32,185 females, n = 9675 males, and n = 1527 participants who identified as other. The prevalence of anxiety ranged from 13.3%–100% in all study populations, with a pooled prevalence of 36%.
Five studies found that the prevalence of anxiety was higher in healthcare workers than in other professions, and this included clinical, non-clinical, and administrative healthcare workers [30,40,78,80,111][27][37][75][77][108]. A greater prevalence of anxiety was found in frontline healthcare responders compared to second-line or non-COVID-19 healthcare workers, and this was highlighted in twelve papers [29,30,34,43,48,51,53,69,74,76,109,113][26][27][31][40][45][48][50][66][71][73][106][110]. This was further endorsed, as healthcare staff not working in COVID-19 epicentres scored lower for anxiety [57][54]. Amongst clinical healthcare workers, more studies found that nurses suffered to a greater level from anxiety than physicians [53,69,73,95][50][66][70][92]. However, this was countered by Lie and colleagues [74][71], where it was found that physicians displayed more anxiety-like symptomology than nurses. Non-clinical healthcare workers, such as administrative staff and clerks, scored higher on anxiety psychometric measurements than clinical staff [38,51,58][35][48][55]. One study contradicted this, suggesting that anxiety in clinical staff was more significant than that that observed in non-clinical staff [76][73].
A lack of resources, including testing equipment and personal protective equipment (PPE), increased the likelihood of anxiety symptoms amongst hospital staff [104,113][101][110]. Additional anxiety was promoted by the worry of infecting family members with COVID-19 or being infected themselves [69[66][74],77], hence there was a strong association between job risk and anxiety [95][92]. Hacimusalar and colleagues found that situational anxiety was much higher in healthcare staff, whereas general anxiety was more common in the broader population [53][50]. During subsequent waves of COVID-19 infection, anxiety levels worsened among healthcare workers [52][49]. The increased demand in working hours exposed healthcare workers, both clinical and non-clinical, to be more at risk [74,113][71][110]. The occurrence of medical violence during peak COVID-19 periods also exacerbated mental health conditions. In ten studies, females were found to have increased levels of anxiety [38,48,51,57,69,77,95,104,109,113][35][45][48][54][66][74][92][101][106][110]. Five papers reported that younger healthcare workers such as trainees experienced more anxiety than older workers [48,51[45][48][66][70][110],69,73,113], but others reported that older healthcare workers were the more affected group [57,58,109][54][55][106]. The existence of a prior mental health illness or living alone were also reported as significant risk factors [58,73,104][55][70][101].

5. University Students

Eight papers focused on the prevalence of anxiety in university students [36,47,54,60,68,83,98,106][33][44][51][57][65][80][95][103]. The total sample size of the student group was n = 183,390, with n = 113,504 females, n = 64,114 males, and n = 2772 participants who identified as other. The prevalence of anxiety ranged from 0–71.5% in all study populations, with the pooled prevalence being 34.7%.
Islaml and colleagues (2020) reported that anxiety amongst university students had worsened compared to pre-pandemic rates and with the duration of lockdowns. Conversely, Kim et al., (2021) reported no significant changes in anxiety throughout lockdowns [68][65]. Two papers denoted adverse anxiety related to worry about academics and dissatisfaction with COVID-19 distance learning measures [36,60][33][57]. The impact of restrictions on daily life was proven detrimental to anxiety symptoms [36,83][33][80]. The implications of lockdowns resulted in increased loneliness and lack of social support, and both of these factors were uncovered to be responsible for a rapid increase in clinical anxiety scores [36,46][33][43]. Although restrictive orders caused some populations to experience more anxiety, another study showed that self-efficacy as a result of isolation decreased anxiety [98][95]. Living in a COVID-19 hotspot or personally knowing an infected person were predictors of higher anxiety [54,106][51][103]. Sun and colleagues (2021) found that the threat of being infected with COVID-19 and the stigma associated with that caused university students to be more anxious about contracting the infection [98][95]. Being exposed to more news and to COVID-19 related social media was strongly associated with worsened anxiety [98,106][95][103]. Financial instability caused by the pandemic was a significant factor for increased anxiety in four studies [36,47,98,106][33][44][95][103]. Further, residing with more than five family members was also predictive of anxiety [54][51]. Five studies identified female students as having higher scores of anxiety compared to male students [47,54,98,106][44][51][95][103]. Two studies found that postgraduate students aged in their mid-to-late 20s had higher levels of anxiety when compared to undergraduates [47,60][44][57]. This was opposed by Odriozola-Gonzalez and colleagues (2020), where it was established that undergraduate students were more anxious than postgraduates [83][80].

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