Smartphone overuse, depression & anxiety in medical students during the COVID-19 pandemic.

INTRODUCTION: Medical students have made particular use of smartphones during the COVID-19 pandemic. Although higher smartphone overuse has been observed, its effect on mental disorders is unclear. This study aimed to assess the association between smartphone overuse and mental disorders in Peruvian medical students during the COVID-19 pandemic.
METHODS: A cross-sectional study was conducted in 370 students aged between 16 and 41 years (median age: 20) in three universities from July to October 2020. A survey including Smartphone Dependence and Addiction Scale, PHQ-9, and GAD-7 was applied. Prevalence ratios were estimated using generalized linear models.
RESULTS: Smartphone overuse was a common feature among students (n = 291, 79%). Depressive symptoms were present in 290 (78%) students and anxiety symptoms in 255 (69%). Adjusted for confounders, addictive/dependent smartphone use was significantly associated with presence of depressive symptoms (PR = 1.29, 95% CI: 1.20-1.38 for dependent use; PR = 1.30, 95% CI: 1.12-1.50 for addictive use). Also, addictive/dependent smartphone use was significantly associated with presence of anxiety symptoms (PR = 1.59, 95% CI: 1.14-2.23 for dependent use; PR = 1.61, 95% CI: 1.07-2.41 for addictive use).
CONCLUSIONS: Our findings suggest that medical students exposed to smartphone overuse are vulnerable to mental disorders. Overuse may reflect an inappropriate way of finding emotional relief, which may significantly affect quality of life and academic performance. Findings would assist faculties to establish effective measures for prevention of smartphone overuse.

Introduction

The coronavirus disease 2019 (COVID-19) pandemic has tremendously impacted mental health and may be a source of major public health concerns in the coming years [1-5]. It has been shown that around 30–40% of people suffered from depression, anxiety, and insomnia during the pandemic [2,5-7] and these rates have significantly increased compared to previous years [2,8]. Some other studies have indicated a relationship between depression/anxiety and negative situations like family members who were diagnosed or deceased due to COVID-19, financial hardship, relationship problems, presence of insomnia, and suicidal ideation [7-11]. Furthermore, higher burden of emotional distress has led to an increase in demand for smartphones, due to social restrictions adopted by countries affected by the outbreak [12,13]. It has been shown that more than 50% of people have increased smartphone use [12,13], mostly as a way to alleviate from anxiety, isolation, and other issues [14].

The use of smartphones has increased over the years, enabling closer social communication. The Global System for Mobile Communications published a report [15] estimating that two thirds of the Latin American population has a smartphone. In Peru, according to the National Institute of Statistics [16], 93% of households have at least one smartphone with easy access to the internet. However, overuse of these devices has been linked to alarming rates of depression and anxiety [17], mainly because of distressing seeking of social reassurance [18].

It is estimated that 27% and 34% of medical students suffer from depression and anxiety worldwide [19,20]. Medical students are more likely to suffer higher rates of mental disorders than the general population [19,20], as time is spent largely on integrating concepts of basic and clinical science, putting knowledge into practice through hospital clerkships, learning to interact with patients, solving problems in life-threatening situations, and being constantly evaluated by exams and professors. The pandemic may have increased the burden of mental health problems in medical students, in particular because learning methods shifted to virtual mode, excluding many skills essential for their professional development. In this context, it is likely that smartphones were used more often for emotional support, increasing the probability of overuse even more than other student groups [13,21]. Prior research has reported a 30–40% prevalence of smartphone overuse in medical students [22,23]; however, we did not find recent reports in the current pandemic.

The relationship between smartphone overuse and mental disorders has been widely reported in university students and similar populations [24]. However, there are no consensus on which study variable represents the outcome, arguing in some cases a bidirectional association [25]. For example, Demirci et al. found that smartphone overuse was an independent predictor of high depression/anxiety scores, while Matar Boumosleh proposed a reverse order of association [26,27]. In the case of medical students, we found studies reporting only a unidirectional association: Chen et al. found anxiety and depression as independent factors for smartphone addiction [23], and Lei et al. found a positive, no adjusted linear association between depression/anxiety scores and smartphone addiction scores [22].

In addition, some studies among university students addressed the association of interest during the COVID-19 pandemic. Overall, these studies proposed a unidirectional association (depression and anxiety as predictors of smartphone overuse), but have shown conflictive results [21,28-30]. In the case of medical students, we found only a study in China that reported an association between problematic smartphone use and anxiety using a structural equation model analysis [31]. However, to our knowledge there are no additional reports exploring the independent effect of smartphone overuse on mental disorders among medical students. The current gap needs to be addressed assuming the risk of long-term mental disorders in this population [32].

Medical students should regulate the use of smartphones as part of a healthy lifestyle, especially at a crucial time like the COVID-19 pandemic. As virtual interaction has prevailed in education and daily activities, evidence is needed in different sociocultural contexts. Our aim was to better understand how the pandemic has influenced the association between smartphone overuse and mental disorders in Peruvian medical students. Understanding this association would provide objective information that would assist faculties in targeted interventions and preventive programs to improve medical students’ quality of life and academic performance.

For this purpose, we formulated the following research questions: 1) How common is presence/severity of depressive and anxiety symptoms as well as smartphone overuse in Peruvian medical students during the pandemic? 2) Are presence rates of depressive and anxiety symptoms higher in students who experience negative situations during the pandemic? 3) To what extent does smartphone overuse lead to presence of depressive and anxiety symptoms in this context? Our hypotheses were that 1) medical students would report higher presence/severity rates of depressive and anxiety symptoms, and higher rates of smartphone overuse during the COVID-19 pandemic [13,21]; 2) there would be higher presence rates of depressive and anxiety symptoms among students that experienced negative situations during the pandemic [7-11]; and 3) smartphone overuse would independently and significantly contribute to the higher presence rates of depressive and anxiety symptoms [31].

Methods

Study design

We conducted a cross-sectional survey study in medical students from Piura, Peru in the context of COVID-19 pandemic. Data collection occurred between July and October 2020, a period in which Peru was exposed to the first pandemic wave and established general lockdown with strict social distancing measures, such as restricted access to public spaces and limited hours of pedestrian transit. In this context, universities fully embraced e-learning platforms to deliver medical education.

Students were receiving online classes during the study period. A convenience sampling method was used. To estimate the total number of students, three authors communicated with class presidents from each university. Surveys were designed using Google forms and shared with an invitation message through common WhatsApp groups. Informed consent was displayed on the first page.

Participation was voluntary and the informed consent explained the study objective and confidential treatment of data. Information was stored in anonymized databases. After the survey, we invited all medical students from the three universities to participate in educational sessions provided by psychiatrists. These sessions were conducted as a way of thanking the participants and universities for their support of the study, and as a contribution to the prevention of smartphone overuse in medical students.

Participants

This study initially considered the entire student population, regardless of the course the students were taking. Individuals that completed the informed consent form and responded to the survey were included. Inclusion of participants was also based on whether they reported owning a smartphone with Internet access for use in daily activities. Exclusion occurred in individuals with a self-report of diagnosed depression, treatment with antidepressants in the last year, and age under 18 years. Students were asked if they met any of these selection criteria before starting the survey. Of these, thirty-eight were excluded on the basis of age alone. We obtained a sample of 375 students who met the selection criteria, of which five refused to participate in the study (they checked “no” on the informed consent form). The response rate was 98.6%.

The sample consisted of 370 students from three universities (n1 = 151, n2 = 121, n3 = 98), which represented 16.6% of the population. Median age was 20 (from 16 to 41 years) and 61.9% were female. Characteristics of the sample are detailed in Table 1.

Table 1

Sample characteristics.

Variables	n	%
Age *	20	16–41
Sex
Male	141	38.11
Female	229	61.89
Academic year
First	68	18.38
Second	72	19.46
Third	70	18.92
Fourth	68	18.38
Fifth	40	10.81
Sixth	35	9.46
Seventh	17	4.59
Marital status
No single	7	1.89
Single	363	98.11
Body mass index
Low	15	4.05
Normal	227	61.35
Overweight	100	27.03
Obesity	28	7.57
Hours of sleep †	6.24	1.61

*Median (min–max values).

†Mean (standard deviation).

Measures

Depressive symptoms were assessed using the Patient Health Questionnaire-9 (PHQ-9), a 9-item self-report instrument rated on a 4-point Likert scale (0 = not at all, 1 = several days, 2 = more than half the days, and 3 = nearly every day). The PHQ-9 was designed by Kroenke et al. [33] to screen for major depression according to the DSM-IV criteria. The overall scores range from 0 to 27. Symptom severity was categorized as minimal (0–4 points), mild (5–9 points), moderate (10–14 points), moderately severe (15–19 points), and severe (20–27 points). For the purpose of this study, we used a Colombian version [34] of the PHQ-9, which was validated in medical students with similar characteristics to our population. The Cronbach’s alpha coefficient in the Colombian sample was 0.83 [34], while in the present study was 0.91.

Anxiety symptoms were assessed using the General Anxiety Disorder-7 (GAD-7) scale, a 7-item self-report instrument rated on a 4-point Likert scale (0 = not at all, 1 = several days, 2 = more than half the days, and 3 = nearly every day). The GAD-7 was designed by Spitzer et al. [35] to screen for GAD according to the DSM-IV criteria. The overall scores range from 0 to 21. Symptom severity was categorized as minimal (0–4 points), mild (5–9 points), moderate (10–14 points), and severe (15–21 points). We used a Spanish version of the GAD-7 [36] validated in the general population. The Cronbach’s alpha coefficient in the Spanish sample was 0.94, while in the present study was 0.93.

The extent of smartphone use was measured with the Smartphone Dependence and Addiction Scale (SDAS), a 40-item self-report instrument rated on a 5-point Likert scale (0 = totally disagree, 1 = disagree, 2 = neither agree nor disagree, 3 = agree, and 4 = totally agree). The SDAS was designed by Aranda-López et al. [37] to assess problematic use of smartphone in specific Spanish-speaking population. The scale is divided into three components: 1) use, abuse, and addiction to smartphone and its apps (30 items); 2) personality traits (6 items); and 3) monetary expenditure on mobile apps and games (4 items). The overall scores range from 0 to 160, with higher scores indicating higher smartphone dependence. To categorize the extent of smartphone use, scores obtained in each item were averaged. Then, mean scores from each response were grouped to calculate the 25th and 75th percentile of their distribution. These percentiles were considered as cut-off points to define three levels of smartphone use: no dependent use (mean score ≤ 25th percentile), dependent use (mean score between the 25th and 75th percentiles), and addictive use (mean score ≥ 75th percentile). The Cronbach’s alpha coefficient in the original sample was 0.81, 0.76, and 0.71 for components 1, 2, and 3, respectively [37]. In the present study, the Cronbach’s alpha coefficient was 0.93 for the overall scale, and 0.93, 0.71, and 0.76 for components 1, 2, and 3, respectively.

The following potential confounders were included: insomnia, suicidal ideation, problems related to contagion or loss of a family member, relationship problems (defined as whether the participant has suffered a major relationship breakup during the last three months), and financial hardship (defined as whether the participant have suffered from a serious financial problem during the last 3 months). Insomnia was assessed using the Insomnia Severity Index (ISI), a 7-point self-report instrument rated on a 5-point Likert scale (from 0 = not at all, to 4 = extremely). The ISI was developed by Bastien et al. [38] to quantify perceived insomnia severity following DSM-IV criteria. The overall scores range from 0 to 28. Insomnia severity was categorized as no clinically significant (0–7 points), subthreshold (8–14 points), moderate (15–21 points), and severe (22–28 points). We used a Spanish version [39] of the ISI, which was validated in medical students and their social networks. The Cronbach’s alpha coefficient in the Spanish sample was 0.82 [39], while in the present study was 0.87. Suicidal ideation was measured using the last item of the PHQ-9 (“how often have you been bothered over the past 2 weeks by thoughts that you would be better off dead, or thoughts of hurting yourself in some way?”). Suicidal ideation was positive if participants gave any response other than "not at all". The other confounders were measured using yes/no questions.

Data analysis

Variables of interest were initially described with frequencies (n, %). For analysis purposes, presence of depressive/anxiety symptoms was defined as the manifestation of any level of symptom severity (from mild to severe). Therefore, the variables followed a dichotomous distribution (0 = absence, 1 = presence) to facilitate interpretation for decision-making. To statistically compare the presence rate of depressive/anxiety symptoms by covariates, bivariate analyses were performed using chi-square tests. The effect size was measured with Cramér’s V (φc). To assess the association of smartphone overuse and presence of depressive/anxiety symptoms, generalized linear models were used with a Poisson distribution, log link function, and robust variance. Universities were considered as clusters assuming that each institution had a particular effect on the association of interest. Multivariate analysis was performed adjusting for potential confounders (age, sex, marital status, body mass index, family member diagnosed with COVID-19, family member deceased due to COVID-19, financial hardship, relationship problems, insomnia, and suicidal ideation). Prevalence ratios (PR) and 95% confidence intervals were reported. The significance level was set at 5%. Statistical analysis was performed in Stata v.16.1.

Ethical approval

The study was approved by the research ethics committee of the Universidad Cesar Vallejo (Piura, Peru). All participants gave informed consent before continuing with the survey. We followed the ethical principles according to the Declaration of Helsinki. Data were used only for research purposes and remained confidential.

To safeguard the possible emotional distress related to some sensitive questions, we tried to carefully explain these items and clearly mentioned that the survey was anonymous and that they were free to withdraw their participation at any time during the study. In addition, we tried to emphasize that their contribution would be very important to understand the problem of excessive use of smartphones and that through them preventive measures could be provided for the benefit of students in general. Although the educational sessions were conducted to all students due to the anonymity of the surveys, we provided a link at the end of the survey with content on emotional support, prevention of negative emotional states, and contact numbers for mental health centers.

Results

Descriptive statistics of study variables are presented in Table 2. Depressive symptoms were present in 290 (78%) students. Mild symptoms were the most prevalent (n = 119, 32%), followed by moderate (n = 79, 21%), moderately severe (n = 55, 15%), and severe (n = 37, 10%). Anxiety symptoms were present in 255 (69%) students. Mild symptoms were the most prevalent (n = 113, 31%), followed by moderate (n = 82, 22%) and severe (n = 60, 16%). Smartphone overuse was a common feature among students (n = 291, 79%), of whom the majority experienced dependent use (n = 251, 68%) followed by addictive use (n = 40, 11%).

Table 2

Descriptive statistics of study variables (n = 914).

Variables	n	%
Family member diagnosed with COVID-19
No	146	39.46
Yes	224	60.54
Family member deceased due to COVID-19
No	276	74.59
Yes	94	25.41
Financial hardship
No	247	66.76
Yes	123	33.24
Relationship problems
No	298	80.54
Yes	72	19.46
Severity of insomnia
No clinically significant	119	32.16
Subthreshold	169	45.68
Moderate	76	20.54
Severe	6	1.62
Suicidal ideation
No	243	65.68
Yes	127	34.32
Level of smartphone use
No dependent	79	21.35
Dependent	251	67.84
Addictive	40	10.81
Severity of depressive symptoms
Minimal	80	21.62
Mild	119	32.16
Moderate	79	21.35
Moderately severe	55	14.86
Severe	37	10.00
Severity of anxiety symptoms
Minimal	115	31.08
Mild	113	30.54
Moderate	82	22.16
Severe	60	16.22

Presence of depressive and anxiety symptoms was compared for each variable of interest, as illustrated in Table 3. Presence of depressive symptoms was moderately associated with addictive smartphone use (addictive use 100% vs. dependent use 82%, p < 0.001, φc = 0.32). Presence of anxiety symptoms was strongly associated with addictive smartphone use (addictive use 98% vs. dependent use 74%, p < 0.001, φc = 0.37).

Table 3

Presence of depressive and anxiety symptoms according to variables of interest.

Variables	n	%	χ2	df	p	φc
Presence of depressive symptoms (n = 290)
Relationship problems
No	223	74.83	11.36	1	0.001	0.18
Yes	67	93.06
Severity of insomnia
No clinically significant	60	50.42	85.94	3	<0.001	0.48
Subthreshold	148	87.57
Moderate	76	100.00
Severe	6	100.00
Suicidal ideation
No	164	67.49	49.53	1	<0.001	0.37
Yes	126	99.21
Level of smartphone use
No dependent	44	55.70	37.04	2	<0.001	0.32
Dependent	206	82.07
Addictive	40	100.00
Presence of anxiety symptoms (n = 255)
Relationship problems
No	193	64.77	12.34	1	<0.001	0.18
Yes	62	86.11
Severity of insomnia
No clinically significant	46	38.66	84.76	3	<0.001	0.48
Subthreshold	130	76.92
Moderate	73	96.05
Severe	6	100.00
Suicidal ideation
No	139	57.20	45.38	1	<0.001	0.35
Yes	116	91.34
Level of smartphone use
No dependent	31	39.24	50.42	2	<0.001	0.37
Dependent	185	73.71
Addictive	39	97.50

To assess the independent association between smartphone overuse and presence of depressive and anxiety symptoms, Poisson regression analysis was performed adjusting for cluster effect within universities and potential confounders (age, sex, marital status, body mass index, family member diagnosed with COVID-19, family member deceased due to COVID-19, financial hardship, relationship problems, insomnia, and suicidal ideation). In the unadjusted analysis, addictive smartphone use (PR = 1.80, 95% CI = 1.42–2.27) and dependent smartphone use (PR = 1.47, 95% CI = 1.17–1.86) were significantly associated with presence of depressive symptoms. After model adjustment, the magnitude of association was still significant but reduced by 50% and 18%, respectively. In the unadjusted analysis, addictive smartphone use (PR = 2.49, 95% CI = 1.59–3.87) and dependent smartphone use (PR = 1.88, 95% CI = 1.35–2.61) were significantly associated with presence of anxiety symptoms. After model adjustment, the magnitude of association was still significant but reduced by 88% and 29%, respectively. More details are shown in Table 4.

Table 4

Regression results adjusted for cluster effect within universities.

Level of smartphone use	Presence of depressive symptoms				Presence of anxiety symptoms
	Unadjusted		Adjusted*		Unadjusted		Adjusted*
	PR	95% CI	PR	95% CI	PR	95% CI	PR	95% CI
No dependent	Ref.		Ref.		Ref.		Ref.
Dependent	1.47	1.17–1.86	1.29	1.20–1.38	1.88	1.35–2.61	1.59	1.14–2.23
Addictive	1.80	1.42–2.27	1.30	1.12–1.50	2.49	1.59–3.87	1.61	1.07–2.41

*Adjusted for age, sex, marital status, body mass index, family member diagnosed with COVID–19, family member deceased due to COVID–19, financial hardship, relationship problems, insomnia, and suicidal ideation.

Discussion

Prevalence of smartphone overuse was notably high (79%) in our sample of medical students (11% for addictive use and 68% for dependent use according to the SDAS). To our knowledge, this is the first Peruvian study reporting the rate of smartphone overuse in medical students during the pandemic. Similar results were reported in this context. Hosen et al. found in Bangladeshi students an 87% prevalence of problematic smartphone use [21], while Saadeh et al. found an increased smartphone use in 85% of Jordanian university students (including medical students) [13]. Before the pandemic period, studies showed a lower but heterogeneous prevalence of smartphone overuse in medical students. Estimates were from 37% in Saudi Arabia [40], 45% in India [41], 59% in Egypt [42], to 68% in Brazil [43]. Although these studies used different scales of smartphone addiction, similar frequency patterns are observed and are notoriously higher in the pandemic period. One reason for this finding is the excessive reassurance seeking provided by social media [18]. This scenario may be aggravated by the COVID-19 context, especially due to lockdown, social distance, and loss of family and friends. It is still necessary to provide more information on the prevalence of smartphone overuse during and after the pandemic outbreak, using standardized scales and validating objective cut-off values that allow for adequate comparison.

Depressive symptoms were present in 78% of participants. This result is remarkably higher than estimates found in meta-analyses during (39%, 95% CI = 29–50%) and before (27%, 95% CI: 25–30%) the pandemic period [19,32]. However, similar findings were reported in Peruvian medical students. Two studies found a high prevalence of depressive symptoms (74%) during the first pandemic wave in Peru (similar to our data collection period) [44,45]. Although PHQ-9 was used, both studies have unclear information about how education was delivered. Another study found a prevalence of 60% with DASS-21 [46], but data collection period was after the first wave and possibly online education was delivered. Another notable finding is the 37% prevalence reported during suspension of classes [47], suggesting that academic courses increase the presence rate of depressive symptoms. It must be noted that differences between estimates are related to the instrument used (e.g., PHQ-9, DASS-21, BDI), the cut-off values used to categorize scale scores, and the period in which surveys were applied. Cross-cultural features may also explain differences in the results. In particular, the young Peruvian population traditionally lives with their families for a long time, which generally strengthens emotional ties. This trait could be a protective factor in situations of personal difficulties, but also a detrimental factor when loss of family members occurs. This study adds local information on the prevalence of depressive symptoms during a specific time. Further studies should explore differences in presence/severity of depressive symptoms at other specific pandemic and post-pandemic periods.

Anxiety symptoms were present in 69% of participants. This result is higher than estimates found in meta-analyses during (47%, 95% CI = 35–59%) and before (34%, 95% CI: 29–39%) the pandemic period [20]. Prevalence of anxiety symptoms was unexpectedly higher than prior Peruvian studies (36–57%) conducted during the first wave in Peru [44-47]. However, as with depression scores, differences between estimates are related to the instrument used (e.g., GAD-7, DASS-21, BAI-21), different cut-off values, and the study period. Cross-cultural features would also explain differences in the results. Overall, medical students may suffer higher rates of anxiety due to the sensation of uncertainty, which may vary according to the impact of COVID-19 in each country. Also, distress may occur by fear of contagion, changes in teaching/learning method, and perceived helplessness in a critical situation. This study shows a high prevalence of anxiety symptoms at the initial time of the pandemic in Peru. Further research is needed to understand how anxiety levels varies in the long term.

This study is the first to assess the association between smartphone overuse on mental disorders in Peruvian medical students. Results of regression analysis suggest that the two categories of smartphone overuse (addictive and dependent use) may have an independent effect on depressive and anxiety symptoms. This association was consistent with previous studies during and before the COVID-19 outbreak. In the pre-pandemic period, a meta-analysis found a roughly 3-fold higher prevalence of depression (95% CI = 2.3–4.4) and anxiety (95% CI = 1.2–2.8) in children and young people (including university students) experiencing smartphone addiction [24]. Some other studies before and during the outbreak stated a reverse order of association [22,23,27]. To our knowledge only one study in the COVID-19 context found that smartphone overuse significantly contributed to the presence of anxiety [31]. Interestingly, a longitudinal study in China found a notorious increase in the prevalence of depressive symptoms [48], but no change in smartphone addiction levels, suggesting that smartphone use is not influenced by the COVID-19 context. According to our results, it seems that mental disorders may arise due to smartphone overuse in medical students. This may be a consequence of a frustrated flight from emotional burden due to personal, academic, and environmental factors, a mechanism linked to reassurance seeking [18] that has intensified during the pandemic. It should be noted that some studies indicate an absent association between smartphone overuse and mental disorders [49], and propose that depressive/anxiety symptoms are predictors of addictive smartphone use [25]. Also, the influence of other variables may change the expected association, such as self-control, sleep quality, among others [50]. Our main finding is just a piece of the puzzle and further studies should explore the complex relationship of smartphone use and mental health.

The study findings give general insight into the mental health concerns of medical students during the pandemic, and addresses the problem of smartphone use as a way to worsen mental disorders. The reported association should serve as information that will help medical educators and policymakers create targeted intervention that will reduce mental health problems. In addition, we encourage the establishment of preventive programs to address smartphone overuse, helping students to adopt a healthy relationship with these devices.

This study has several limitations. First, residual confounding is present since some variables associated with mental health were not included (e.g., economic level and social support). Second, selection bias is present since sampling was not stratified by years of study. Third, the results cannot be inferred to the entire study population, as data were collected from only three universities in northern Peru. Fourth, the study design cannot establish a causal relationship between smartphone overuse and mental disorders. Fifth, data collection through online surveys may bias the results due to subjectivity in the responses. However, novel data on smartphone use was shown in Peruvian medical students. Added to the current pandemic context, this study may serve as baseline for future studies at the regional level. Also, the results are based on instruments with adequate psychometric properties, which ensures their internal validity.

Conclusions

A significant number of medical students experience symptoms related to depression, anxiety, and smartphone overuse during the COVID-19 pandemic. Smartphone overuse represents a major source of mental disorders and may reflect an inappropriate way of finding emotional relief, which may significantly affect quality of life and academic performance. These findings would assist faculties to establish effective measures for prevention of smartphone overuse. Further research is needed to overcome the indirect and long-term effects of COVID-19 on mental health of medical students.

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Reviewer #1: Overall comments

The study was conducted in three medical schools in Peru to examine the relationship between overuse of smartphones during the pandemic and mental disorders. The introduction places the study in context and the manuscript provides sufficient information regarding methods, results, and a discussion of findings. The topic itself is relevant and current and likely to be interesting to the readership of the journal. However, there are quite a few shortcomings in terms of reporting and I provided detailed feedback to each section.

Abstract:

• Please check for Grammatical errors and ensure the abstract is written in the past tense throughout. For example, the first line could be better phrased to highlight the issue.

• In describing the results beware of making claims that students had depression or had addiction. A high score on a questionnaire is only a score, to be diagnosed with depression or addiction will require more than a questionnaire. I suggest you may want to rephrase to ‘high score on the addiction …or a positive relationship ….’.

• There is too much description of results and this should be more concise with a focus on the relationship between overuse of smartphone and mental disorders

• Include an overall summary of what the results mean and why understanding this is important.

• What is missing is an overall statement of the potential contribution of findings.

Introduction:

Overall this is well-written and puts the study in context with reference to up-to-date and relevant literature, however, strengthening the rationale is likely to improve the manuscript. To this end, you may want to consider further why understanding the association between smartphone use and mental disorders in medical students is important and why this particular group of students. What is unique about medical students and in what is potential value of findings?

It will also be useful to have a clear research question at the end of the introduction and this should be driven by the literature reviewed in the introduction. Given the quantitative nature of the research, a prediction in the shape of an hypothesis should be offered, as you are already indicating a direction in your title. If you wish to be more explorative and not make a prediction than the title may need changing to ‘use’ rather than ‘overuse’.

What is missing is an overview of research to data on the topic to date. Is this the first study that examined the use of smartphone and mental disorders? In what way your research is similar or different to previous research and what is the research problem or gap it is trying to address?

Methods

Sample

• Names of the three schools are included in the manuscript and you may want t indicate whether consent was given by these institutions. Please seek guidance regarding this issue as participating organisations sometimes agree to participate on the assumption that they are not identified in any publications.

• I am intrigued by how the exclusion criteria were applied? How did you know if students had depression, received treatment etc? was it self-reported or did you have access to record? It will be useful to have some information on this point.

• There is no information regarding the sample / participants. Were all UG students invited or just from a specific year group? How many from each school took part? Sample characteristics should be provided here.

Data collection

• Providing the educational sessions on excessive use of smartphone is good practice but here you could provide a justification as to why this was done. Was it based on findings? Was it to safeguard participants?

Variables

• This section provides information on the outcome, exposure and confounding variables, but it isn’t clear why the variables were defined in such a way as no prediction was made in the introduction regarding direction.

• You have indicated established reliability of the Smartphone Dependence and addiction Scale. What about validity? Has this been established?

• Lines 95-98, you have noted how Insomnia a measured, but what about suicidal ideation, problems related to contagion or loss of a family member, relationship problems and financial problems. Were this assessed via one single question for each, or did you use an established questionnaire?

• The questions asked are emotive and may trigger a set of emotions, please indicate what measures you put in place and whether support was offered to students

Data analysis

Once a research question is included in the introduction and a research hypothesis, this will provide justification for the analysis strategy. Please ensure you clearly state which statistical tests were conducted to examine the research hypothesis.

Ethical consideration

• Please see comment regarding the names of the participating institutions within the manuscript.

• In this section you could also mention issues of safeguarding and support offer to students given the emotive nature of study.

Results

Line 114- 115: Information regarding the sample should be moved to the appropriate section in the Methods section.

Was the survey checked for reliability and validity? Cronbach alpha should have been conducted and reported before inferential statistics. Were data normally distributed? Did it meet the assumptions for further regressions?

Overall this section provides a lot of detail but unfortunately makes for quite a cumbersome read. I suggest it is revised in line with the hypothesis /es that should be included in the introduction.

There are too many long tables, all of which impact the readability of the manuscript so you may want to consider cutting down the information presented ensuring it is focused on the purpose of the study.

Discussion

• Results should not be stated again in the discussion but should be discussed more broadly and in relation to previous literature.

• In comparing results with previous study, please acknowledge potential differences and similarities that may explain the findings. i.e., comparing to China, Brazil, USA, and pre-pandemic, were the same measures used? Are the studies comparable?

• The main issue is wording and you should be careful in stating that participants had depression. As indicated above, a score on a questionnaire is just a score, an indication, it isn’t a diagnosis.

• The discussion should provide more of an interpretation of finding and what it means.

• A lot of the studies included in the discussion should be summarised in the introduction to indicate research to date in the field.

• Beware of overinterpretation of findings and provide a more concise discussion linked to the research question and hypothesis/es you will include in the introduction.

• Clearly state in what was=y your study provided some answers to a research problem, in what way it adds to the existing body of literature on the topic, and make suggestions for further research.

• Please include a discussion of the potential value of findings and how they can inform medical educators. What is the value of findings beyond just telling us that there is a relationship?

Reviewer #2: The manuscript entitled "Smartphone overuse and mental disorders in medical students during the COVID-19

pandemic" is an interesting work related to a mental health risk factors during the COVID-19 pandemic. However, many questions should be resolved before the manuscript will be considered to publication.

1. The introduction is poorly written and needs to be completed. In particular, there is too little literature on variable interests (anxiety, depression, insomnia, smartphone use, etc. during the COVID-19 pandemic. Hundreds of articles have been published since 2019, including meta-analyzes and systematic reviews. Authors should rewrite in the introduction, adding In addition, the relationship between depression / anxiety and other variables in the study was described earlier during and earlier during the COVID-19 pandemic, so this information should be presented in the introduction to make direct hypotheses about the expected associations. If the authors are interested in the prevalence rate, information should be provided in previous studies as a basis for hypotheses.

2. More information is necessary about the situation of the COVID-19 pandemic in the Peru (e.g., which wave, what the restriction levels, lockdown, e-learning or stationairy classes, etc.) during the data were collected.

3. How were the inclusion and exclusion criteria controlled? How many students have been excluded because of each criterion?

5. How many students refused from the participation in the study? What was the response rate?

6. How questionnaires were disseminated?

7. How were the educational sessions disseminated to the participants (available)? Was the survey anonymous?

8. Each questionnaire (PHQ-9, GAD-7, SDAS, ISI) should be comprehensively described, adding information about references to the original and Peruvian version of the instrument, the number of items included in each scale and subscale, response scale shoud be described in details (verbally and digitally), reliablility for each scale and subscale in the original and current sample. Also, demographic variables should be described and all categories of answer should be presented in the Method section.

9. Descriptive analysis should should be showed in the table and commented.

10. The authors stated (lines 103-104): "Student's t test was used after evaluation of normality and homoscedasticity; otherwise, we used the Mann-Whitney U test." but these results are not presented in the manuscript.

11. The results of chi-square tests shoud include more statistics (besides p-value), such as Chi-square statistic with df, and effect size (e.g., phi, Cramer's V, or Cohen's d).

12. It is unclear, how depression and anxiety in Table 2 and Table 3 was assessed (cut-off score should be described in method section, respectively).

13. Discussion should be rewritten, using additional references, which will be added in the Introduction.

**********

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Reviewer #1: No

Reviewer #2: Yes: Aleksandra Rogowska

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15 Apr 2022

Response to the editor’s and reviewer’s comments

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Response: This manuscript has been revised according to the journal style requirements (please see the revised manuscript).

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We will update your Data Availability statement to reflect the information you provide in your cover letter.

Response: The study’s minimal underlying data set was uploaded as a Supporting Information file.

Response to Reviewer #1 comments:

Abstract

• Please check for Grammatical errors and ensure the abstract is written in the past tense throughout. For example, the first line could be better phrased to highlight the issue.

Response: We have checked all this sections and provided a better phrasing.

• In describing the results beware of making claims that students had depression or had addiction. A high score on a questionnaire is only a score, to be diagnosed with depression or addiction will require more than a questionnaire. I suggest you may want to rephrase to ‘high score on the addiction …or a positive relationship ….’.

Response: We have carefully revised the use of these phrases and intended to make a better description of the results.

• There is too much description of results and this should be more concise with a focus on the relationship between overuse of smartphone and mental disorders

Response: We have rewritten this section focusing on the association of interest.

• Include an overall summary of what the results mean and why understanding this is important.

Response: We included an overall summary indicating your suggestion.

• What is missing is an overall statement of the potential contribution of findings.

Response: We have added an overall statement of the potential contribution of findings.

Introduction

Overall this is well-written and puts the study in context with reference to up-to-date and relevant literature, however, strengthening the rationale is likely to improve the manuscript. To this end, you may want to consider further why understanding the association between smartphone use and mental disorders in medical students is important and why this particular group of students. What is unique about medical students and in what is potential value of findings?

Response: We added information regarding the importance of understanding the association between smartphone overuse and mental disorders in medical students, and the potential value of findings, in order to strengthen the rationale of the study.

It will also be useful to have a clear research question at the end of the introduction and this should be driven by the literature reviewed in the introduction. Given the quantitative nature of the research, a prediction in the shape of an hypothesis should be offered, as you are already indicating a direction in your title. If you wish to be more explorative and not make a prediction than the title may need changing to ‘use’ rather than ‘overuse’.

Response: Following the literature review, we added three research questions at end of the introduction. One of them is the primary question related to the association between smartphone overuse and mental disorders, while the two others are secondary and related to the description of variables of interest. Accordingly, we formulated a hypothesis for each question and offered a predictive form of the main hypothesis.

What is missing is an overview of research to data on the topic to date. Is this the first study that examined the use of smartphone and mental disorders? In what way your research is similar or different to previous research and what is the research problem or gap it is trying to address?

Response: This is not the first study that examined the association of interest. However, there is no specific information in medical students addressing the problem of smartphone overuse and mental disorders, although literature has reported data in general students and other population. This gap could be necessary to address in the context of the pandemic assuming potential long-term mental disorders in this group. Furthermore, previous research has reported an association between these variables but with no consensus on whether smartphone overuse or mental disorder is the outcome, assuming in some cases a bidirectional association. We add more information to this gap under the assumption that smartphone overuse has a negative effect on mental health.

Methods

Sample

• Names of the three schools are included in the manuscript and you may want t indicate whether consent was given by these institutions. Please seek guidance regarding this issue as participating organisations sometimes agree to participate on the assumption that they are not identified in any publications.

Response: Ethical consent was given by only one institution. We decided to deidentify the names of the three schools included in the study to ensure confidentiality of data.

• I am intrigued by how the exclusion criteria were applied? How did you know if students had depression, received treatment etc? was it self-reported or did you have access to record? It will be useful to have some information on this point.

Response: Depression and whether they received treatment were self-reported. Therefore, we excluded these participants based on their response. We clarified this in the manuscript.

• There is no information regarding the sample / participants. Were all UG students invited or just from a specific year group? How many from each school took part? Sample characteristics should be provided here.

Response: We added a line explaining that all students were invited to participate in the study. The number of students from each school were clarified.

Data collection

• Providing the educational sessions on excessive use of smartphone is good practice but here you could provide a justification as to why this was done. Was it based on findings? Was it to safeguard participants?

Response: We provided educational sessions to prevent smartphone overuse in all students from the three universities.

Variables

• This section provides information on the outcome, exposure and confounding variables, but it isn’t clear why the variables were defined in such a way as no prediction was made in the introduction regarding direction.

Response: We clarified this methodology by adding more context to the introduction and clarifying the direction of association.

• You have indicated established reliability of the Smartphone Dependence and addiction Scale. What about validity? Has this been established?

Response: Yes, it has been stablished showing adequate validity. We clarified this part the text.

• Lines 95-98, you have noted how Insomnia a measured, but what about suicidal ideation, problems related to contagion or loss of a family member, relationship problems and financial problems. Were this assessed via one single question for each, or did you use an established questionnaire?

Response: We used one single question for each of the indicted variables. For insomnia, we used the last question of the PHQ-9. The other variables were measured using a yes/no question.

• The questions asked are emotive and may trigger a set of emotions, please indicate what measures you put in place and whether support was offered to students

Response: We explained the measures we put in place to safeguard the emotional state of students. Also, we detailed the support we could give participants by providing articles about emotional support, prevention of negative emotional states, and contact numbers for mental health centers.

Data analysis

Once a research question is included in the introduction and a research hypothesis, this will provide justification for the analysis strategy. Please ensure you clearly state which statistical tests were conducted to examine the research hypothesis.

Response: We assured the research question and hypothesis in the introduction. Then, we detailed the reason of each statistical analysis and emphasized which statistical test was conducted to examine the research hypothesis.

Ethical consideration

• Please see comment regarding the names of the participating institutions within the manuscript.

Response: We detailed the name of the institution that gave authorization, but the names of the other institutions were not revealed.

• In this section you could also mention issues of safeguarding and support offer to students given the emotive nature of study.

Response: We added a paragraph mentioning issued of safeguarding and support offer to students given the emotive nature of study. We also emphasized that participants gave informed consent before continuing with the survey.

Results

Line 114- 115: Information regarding the sample should be moved to the appropriate section in the Methods section.

Response: Information from line 114-115 were moved to the participants section, along with part of their corresponding data from Table 1.

Was the survey checked for reliability and validity? Cronbach alpha should have been conducted and reported before inferential statistics. Were data normally distributed? Did it meet the assumptions for further regressions?

Response: Our survey had three questionnaires which was not validated in the present study but used previously validated instruments in similar population. Reliability of the instruments in the present study was reported using the Cronbach alpha coefficient (coefficients are presented in Measures subsection). Data regarding depression and anxiety symptoms were not evaluated for normality because we categorized the data for both outcomes as presence or absence (dichotomous response) according to the severity of symptoms. This was in line with the use of Poisson regression models, which omits the normality assumption. The outcomes met the other assumptions for this regression analysis (Y-values are counts, counts are positive integers, counts follow a Poisson distribution, explanatory variables are continuous, dichotomous, or ordinal, and observations are independent).

Overall this section provides a lot of detail but unfortunately makes for quite a cumbersome read. I suggest it is revised in line with the hypothesis /es that should be included in the introduction.

Response: The results section was revised in line with the hypothesis included in the introduction.

There are too many long tables, all of which impact the readability of the manuscript so you may want to consider cutting down the information presented ensuring it is focused on the purpose of the study.

Response: Tables were reformatted including only information relevant to the study and focused on the purpose of the study.

Discussion

• Results should not be stated again in the discussion but should be discussed more broadly and in relation to previous literature.

Response: First paragraph regarding overview of results was deleted.

• In comparing results with previous study, please acknowledge potential differences and similarities that may explain the findings. i.e., comparing to China, Brazil, USA, and pre-pandemic, were the same measures used? Are the studies comparable?

Response: We updated the literature adding information from a meta-analysis and acknowledging limitation for comparison. Also, we detailed the comparison with previous Peruvian studies conducted during the pandemic period (please revise the two paragraphs from lines 269-298).

• The main issue is wording and you should be careful in stating that participants had depression. As indicated above, a score on a questionnaire is just a score, an indication, it isn’t a diagnosis.

Response: Wording was revised, and we intended to better describe our results.

• The discussion should provide more of an interpretation of finding and what it means.

Response: We have rewritten the discussion focusing on a more detailed interpretation of findings.

• A lot of the studies included in the discussion should be summarised in the introduction to indicate research to date in the field.

Response: We summarized studies included in the discussion, as well as added some new information in both sections.

• Beware of overinterpretation of findings and provide a more concise discussion linked to the research question and hypothesis/es you will include in the introduction.

Response: We carefully revised this section and provided a more concise discussion linked to our main hypotheses.

• Clearly state in what was=y your study provided some answers to a research problem, in what way it adds to the existing body of literature on the topic, and make suggestions for further research.

Response: We stated how our study provided some answer to a research problem, the way it adds to the existing body of literature, and made suggestions for further research.

• Please include a discussion of the potential value of findings and how they can inform medical educators. What is the value of findings beyond just telling us that there is a relationship?

Response: We added a discussion of potential value of findings and how they can inform medical educators (lines 320-325).

Response to Reviewer #2 comments:

1. The introduction is poorly written and needs to be completed. In particular, there is too little literature on variable interests (anxiety, depression, insomnia, smartphone use, etc. during the COVID-19 pandemic. Hundreds of articles have been published since 2019, including meta-analyzes and systematic reviews. Authors should rewrite in the introduction, adding In addition, the relationship between depression / anxiety and other variables in the study was described earlier during and earlier during the COVID-19 pandemic, so this information should be presented in the introduction to make direct hypotheses about the expected associations. If the authors are interested in the prevalence rate, information should be provided in previous studies as a basis for hypotheses.

Response: The introduction has been revised and rewritten. In particular, we added more information on the variables of interest during the pandemic, including information from meta-analyzes. We also added a new paragraph describing the association between smartphone overuse and mental disorders (lines 76-92), using relevant studies reported before and during the pandemic. We also used this information to formulate the study hypotheses (lines 104-110).

2. More information is necessary about the situation of the COVID-19 pandemic in the Peru (e.g., which wave, what the restriction levels, lockdown, e-learning or stationairy classes, etc.) during the data were collected.

Response: More information was added about the situation of the COVID-19 pandemic in Peru (lines 114-118).

3. How were the inclusion and exclusion criteria controlled? How many students have been excluded because of each criterion?

Response: Selection criteria was controlled by self-report of participants before starting the survey. Students were asked if they met any of the criteria. 38 students were excluded because of age < 18.

5. How many students refused from the participation in the study? What was the response rate?

Response: Five participants refused to participate in the study. The response rate was 98.6%.

6. How questionnaires were disseminated?

Response: Questionnaires were disseminated through common WhatsApp groups provided by class presidents from each university.

7. How were the educational sessions disseminated to the participants (available)? Was the survey anonymous?

Response: Educational sessions were disseminated openly to all students from study universities. This was because we did not have information about the names of the students.

8. Each questionnaire (PHQ-9, GAD-7, SDAS, ISI) should be comprehensively described, adding information about references to the original and Peruvian version of the instrument, the number of items included in each scale and subscale, response scale shoud be described in details (verbally and digitally), reliablility for each scale and subscale in the original and current sample. Also, demographic variables should be described and all categories of answer should be presented in the Method section.

Response: Each questionnaire was comprehensively described adding information suggested (please revise Measures subsection).

9. Descriptive analysis should should be showed in the table and commented.

Response: Descriptive analysis was showed in the table and commented (lines 219-225).

10. The authors stated (lines 103-104): "Student's t test was used after evaluation of normality and homoscedasticity; otherwise, we used the Mann-Whitney U test." but these results are not presented in the manuscript.

Response: We initially used these tests to compare the presence of depressive/anxiety symptoms according to numeric variables such as age and hours of sleep. We have modified this part since these variables did not represent the main findings in our study.

11. The results of chi-square tests shoud include more statistics (besides p-value), such as Chi-square statistic with df, and effect size (e.g., phi, Cramer's V, or Cohen's d).

Response: We added more detail of the results of chi-square tests, including chi-square statistic, df, and effect size using Cramer's V (Table 3).

12. It is unclear, how depression and anxiety in Table 2 and Table 3 was assessed (cut-off score should be described in method section, respectively).

Response: A cutoff score for defining the presence of depressive and anxiety symptoms was described in the methods section (lines 191-194).

13. Discussion should be rewritten, using additional references, which will be added in the Introduction.

Response: We have revised and rewritten the discussion, adding references that are also part of the introduction.

Submitted filename: Response to Reviewers.docx

Click here for additional data file.

20 Jun 2022

2 Aug 2022

Response to Reviewer #3 comments:

Brief message to reviewer 3: We want to thank reviewer 3 for their comments. However, we have noticed that the review of the manuscript was based on the original version and not on the revised one with track changes. Despite of this, we have responded to the comments and added all the suggestions.

Introduction

1. Although the authors have included references from previous reviewers, it is still too brief introduction. The title of the article refers to smartphone overuse and mental disorders. In the introduction, there is a short presentation of both concepts, but it is scarce. It is recommended that the authors include more information and data on the prevalence of smartphone overuse in addition to data on the prevalence of other mental disorders. The introduction talks mainly about depression, so including information on anxiety and insomnia, later evaluated in this study, will provide a greater understanding of the topic.

Response: Thank you for your suggestions. We have previously revised the introduction and focused on depression & anxiety as the outcome measures in this study. We have provided prevalence data on both outcomes as well as on smartphone overuse. We have also highlighted the relationship between depression/anxiety & smartphone overuse, adding current literature on this association. Finally, we stated the research questions and study hypotheses.

Methods

2. Regarding the sample selection criteria, the authors are suggested to be more specific. Are all medical students included, regardless of the course they are taking? Is it an inclusion criterion that they completed the informed consent and responded to the survey? Is access to the smartphone exclusively at home or also in other places?

Response: Thank you. We have specified the information on selection criteria following your suggestions (lines 131-134).

3. An online survey is used to data collection. This method has the relevant risk of subjectivity, which may bias the data. It is recommended that the author consider this aspect on future research. In addition, it should be included as a limitation of the study.

Response: Thank you. We have included this limitation on lines 337-338.

4. It is mentioned that following the survey, three educational sessions on the excessive use of smartphones were given. Were these sessions carried out with a specific objective and is the impact of these sessions evaluated in any way?

Response: Thank you. In the latest version of the manuscript, we mentioned the reason for this activity. We have tried to clarify this information further (lines 127-129). Unfortunately, due to logistic limitations we could not gather data on the impact of these sessions.

5. In this study, different questionnaires are applied to obtain the data. There is a specific questionnaire for depression and another for anxiety. Although other psychopathological variables such as insomnia or suicidal ideation are measured, both the introduction and the results deal mainly with depression and anxiety. Therefore, the authors are asked if the article should not have another title referring specifically to depression and anxiety and not to mental disorders.

Response: Thank you for your feedback. We agree that the title should be more specific according to the two mental health outcomes (depression and anxiety). We have modified the title as suggested.

Results

6. In the results section, reference is made to relationship problems, what do the author mean by this concept? (Page 9, line 135).

Response: Thank you. We have added the definition of this variable to clarify its meaning (lines 181-182).

Discussion

7. The authors are encouraged to review the discussion. They are requested to be uniform when referencing citations in the text. Sometimes the reference is indicated after the punctuation mark, and other times between periods. For example: “However, a study in Korea stated that, rather than addiction, mobile phone users experience “overdependence”, a condition developing in some of them. (21) (Page 11, lines 167-168). And “A unidirectional relationship with depression was also proposed as a possible cause of smartphone addiction. (37, 38). (Page 12, lines 191-193).

Response: Thank you. In the latest version of the manuscript, we have revised all the citations following the journal requirements.

8. In addition, the authors are suggested to review paragraph 4 of the discussion. The way in which the data are presented is confusing (page 11, lines 169-179).

Response: Thank you. We have previously reviewed this paragraph. Please see paragraphs 2 and 3 of the discussion (pages 15-16, lines 275-304).

Submitted filename: Response to Reviewer 3.docx

Click here for additional data file.

11 Aug 2022

Smartphone overuse, depression & anxiety in medical students during the COVID-19 pandemic

PONE-D-22-01374R2

Dear Dr. Valladares-Garrido,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

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Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #3: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #3: Yes

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #3: Yes

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4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #3: Yes

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PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #3: Yes

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19 Aug 2022

PONE-D-22-01374R2

Smartphone overuse, depression & anxiety in medical students during the COVID-19 pandemic

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