Natl. J. Physiol. Pharm. Pharmacol. (2025), Vol. 15(3): 246-252

Original Research

10.5455/NJPPP.2025.v15.i3.5

Smartphone screen time and sleep quality in MBBS students

Sophiamma Joseph¹, Simmy Kurian¹, Saritha J. Shenoy^1* and Geethadevi Madhavikuty²

¹Department of Physiology, Government Medical College, Kerala University of Health Sciences, Kottayam, Thrissur, India

²Department of Community Medicine, Government Medical College, Kerala University of Health Sciences, Kottayam, Thrissur, India

*Corresponding Author: Saritha J. Shenoy. Department of Physiology, Government Medical College, Kerala University of Health Sciences, Thrissur, India. Email: ajaikamathsaritha [at] gmail.com

Submitted: 02/12/2024 Accepted: 11/02/2025 Published: 31/03/2025

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Abstract

Background: Smartphone use and other screen-emitting devices have surged, particularly among college students. Such devices are often used for both academic and recreational purposes, potentially affecting sleep quality.

Aim: To explore the correlation between smartphone screen time (ST) and sleep quality among MBBS students.

Methods: This cross-sectional study was conducted at the Government Medical College, Kottayam. A sample size of 370 MBBS students was selected using simple random sampling. Data on sleep quality were collected using the Pittsburgh Sleep Quality Index (PSQI), while ST was measured using the Stay-Free ST app. Statistical analysis was conducted using Jamovi software, and associations were determined using the chi-square test and ANOVA.

Results: The mean ST was higher among male students (5.55 ± 3.98 hours) than among female students (4.84 ± 1.89 hours). Sleep quality was similarly affected. A significant difference in ST was observed across academic phases, with third-year students reporting the highest mean ST (6.23 ± 2.04 hours). Poor sleep quality was reported by 49.8% of students, with a strong correlation observed between increased ST and lower sleep efficiency. The mean PSQI score of males was 6.00 ± 2.53, for females 5.74 ± 2.46, and across phases was between 5 and 6.

Conclusion: The study concludes that there is a significant association between excessive smartphone use and poor sleep quality among MBBS students. Interventions aimed at reducing ST, particularly before bedtime, can help improve sleep quality and overall well-being among students.

Keywords: Smartphone screen time, Sleep quality, PSQI tool, Medical students.

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Introduction

Optimum and good quality sleep is essential for the health and equilibrium of biological functions. It plays a critical role in cognition and memory and governs cell homeostasis through the secretion of hormones. Poor sleep quality is non-restorative and is a key symptom of several psychiatric disorders, insomnia, and chronic illness (Saxena et al., 2021). Scientific evidence from epidemiological studies has observed the association of sleep disorders with cardiovascular mortality, stroke, impaired glucose tolerance, and immune dysfunction. Disharmony of sleep cycles leads to an aberrant release of feeding hormones, causing desynchronization of time-restricted feeding and nutritionally driven rhythms that affect the dietary pattern and associated determinants (Brand and Kirov, 2011). College life is the transitional period during which a teenager matures into a responsible adult, both physically and mentally. During this time, the use of electronic gadgets and accessibility to various social platforms has increased for personal and academic purposes. The duration of sleep requirement depends on the patient’s age. The recommended sleep duration for the age group ≥18 years is 7–9 hours per day (Vélez et al., 2013). During adolescence, it was found that there are dramatic maturational changes in sleep patterns and neurobiological regulation. Adequate sleep enhances academic performance, but college students are unaware of the importance of sleep on physical and mental health and learning. Among the causes of sleep disturbances, screen time (ST) and light-emitting devices used during late hours play a major role. ST is the amount of time spent using a device with a screen, such as a smartphone, computer, television, or video game console (Merriam-Webster, 2020). Although sleep problems are a growing public health issue with the advancement of technology, especially among adolescents and young adults, it has received little attention in India. A study reported that the magnitude of smartphone addiction among teens and youngsters in India ranged from 39% to 44% (Davey and Davey, 2014). This study aimed to assess the quality of sleep and to determine its correlation with ST among medical students.

The use of electronic gadgets has increased tremendously in the general population because of technological revolutions. Among them, college students are exposed to the screen both academically and socially. ST affects sleep quality and daytime sleepiness. In the study, approximately 49.8% of the students had poor sleep quality (Twenge et al., 2019). A study on Indian medical students reported that 2 out of 10 medical students suffer from poor sleep quality, and among undergraduates. Around 62.6% had poor sleep quality (Chutani et al., 2020). Female college students have poor sleep quality and higher ST than males. The Pittsburgh Sleep Quality Index (PSQI) scores showed a weak but significant correlation with the academic year (rho=−0.19, p=0.004). Unlike sleep scores, the burnout dimensions did not correlate well with the academic year (Shad et al., 2020). Poor sleep quality was significantly higher in a Taiwanese study. Of the 413 students, 41.4% had poor sleep quality. Gender, academic stress, relaxed psychological status, good physical status, and sleep hygiene practices had significant direct effects on sleep quality; relaxed psychological status had a significant direct effect on sleep hygiene practices and an indirect effect on sleep quality via sleep hygiene practices (Li et al., 2016). Poor PSQI score was significantly associated with an ST of >10 hours in adolescents and a positive and significant relationship (Sun et al., 2022). Students took equal time to sleep irrespective of ST, although the duration of sleep was significantly decreased in those with ST >10 hours, which extended into the morning period in 45% of the students [9 AM and beyond]. With an average of 5–6 hours of sleep, the proportion of hours in bed was significantly less in those with ST >10 hours [sleep efficiency of only 65%], which is due to screen watching more at night, which may be causing a physiological delay in the rise of sleep hormone due to the light emitted from the screen extending its peak extending sleep into the next day (Famodu et al., 2018).

Objectives

To estimate ST and sleep quality among MBBS students using the Stay-free ST app for smartphones and the PSQI questionnaire, respectively.

To determine the association between Smartphone ST and sleep quality among MBBS students.

Hypothesis statement

There is a correlation between sleep quality and Smartphone ST among MBBS students.

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Materials and Methods

This cross-sectional study used quantitative methods for analysis. This research was conducted at the Department of Physiology, Government Medical College, Kottayam. A total of 370 MBBS students in various phases were selected by a simple random sampling process. Ethical approval was taken and students were briefed on the processes and all the documentation of the project. After obtaining informed consent, the demographic details of the students were collected.

The quality and pattern of sleep were assessed using the PSQI questionnaire under seven components: subjective sleep quality, sleep latency, sleep duration, sleep disturbances, habitual sleep efficiency, use of sleeping medications, and daytime dysfunction over the past month. The collected data were entered into a Microsoft Excel sheet. PSQI scores were categorized into two groups ≤5 good sleep and >5 poor sleep quality. The Smartphone ST was estimated using the Stay Free ST app for Android phones, which is free and easily downloadable. ST was categorized into ≤2 normal & >2 high (WHO recommended ST).

Inclusion criteria

MBBS students of both genders from the first year to the final year were willing to participate in this study.

Exclusion criteria

Students with known sleep disorders.

Students with known chronic illnesses like liver and kidney diseases and psychiatric illnesses.

Students on long-term use of medications affecting sleep (antihistamines, antidepressants, CNS stimulants, etc.

Data management and statistical analysis

Data were entered in Microsoft Excel and analyzed using Jamovi software. The categorical variables were expressed as percentages and the continuous variables as mean and standard deviation. An association between sleep quality and ST in different batches was found using the chi-square test and ANOVA.

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Results

The study included 370 students, with a sex distribution of 149 males (40.3%) and 221 females (59.7%) (Fig. 1). The majority of participants were in Phase I (36.5%), followed by Phase II (27.3%), Phase III part 1 (21.1%), and Phase III part 2 (15.1%) (Table 1).

The average daily ST was 5.55 ± 3.98 hours for male students and 4.84 ± 1.89 hours for female students (Table 2). When analyzed by academic year, third-year part 2 students reported the highest average ST at 6.23 ± 2.04 hours, while first-year students reported the lowest at 4.47 ± 1.59 hours. This finding suggests that as students progress through medical school, their ST increases, potentially due to heightened academic and clinical responsibilities. The p value for gender was <0.05 which means statistically significant, and across genders is <0.001 which means highly significant (Table 3).

In terms of sleep quality, 49.8% of the students were categorized as having poor sleep quality based on their PSQI scores of >5. The distribution of sleep quality was relatively consistent across genders, with males having a mean PSQI score of 6.00 ± 2.53 and females at 5.74 ± 2.46 (Table 4). However, the correlation between ST and poor sleep quality was significant, particularly among students with ST >2 hours per day. The p value was > 0.05 and not statistically significant (Table 5).

Fig. 1. Frequencies of the batch.

Table 1. Frequencies of gender.

Table 2. Daily average screening time by gender.

Table 3. Daily average screening time for phases.

Table 4. Total PSQI score according to gender.

Table 5. Total PSQI score for the phases.

Table 6. Subjective sleep quality for gender.

Table 7. Subjective sleep quality for phases.

Table 8. Subjective sleep latency for gender.

Table 9. Subjective sleep latency for phases.

Table 10. Sleep duration for gender.

Table 11. Sleep duration for phases.

Table 12. Sleep efficiency for gender.

Table 13. Sleep efficiency for phases.

Table 14. Sleep disturbances for gender.

Table 15. Sleep disturbances for phases.

Table 16. Sleep medication for genders.

Table 17. Sleep medication for phases.

Table 18. Daytime dysfunction for genders.

Table 19. Daytime dysfunction for phases.

Fig. 2. Frequencies of sleep disorders.

The mean score of subjective sleep quality in both genders (Table 6) and across phases is 1, which means the sleep quality is fairly good. The p value is >0.05 and is not statistically significant (Table 7).

The average sleep latency time reported was less than 15 minutes, except for phase III part 2 students (15–30 minutes). The p value was >0.05 and not statistically significant (Tables 8 and 9).

The average score of sleep duration of both genders (Table 10) and across phases is between 1 and 2, which means the duration was between 5 and 6 hours/day. The p value was >0.05 and was notstatistically significant (Table 11).

The mean score of sleep efficiency was less than 0 in both genders (Table 12) and across phases that means sleep efficiency was >85% (Table 13).

The average score for sleep disruptions was below 0 for both sexes (Table 14) and across all phases, except for phase I, where it reached 1, which was significant (Table 15).

The average score for sleep medications was 0 for both sexes and across all phases(Tables 16 and 17).

The average score for daytime dysfunction was between 1 and 2 for both sexes (Table 18) and across all phases (Table 19). The prevalence of sleep disturbances increased with higher ST, especially among third-year students. Those who reported more than 5 hours of daily ST were also more likely to experience sleep latency (difficulty falling asleep), reduced sleep efficiency, and daytime dysfunction.

A number of students reported experiencing specific sleep disturbances. The most common issues were twitching (27.6%), confusion (22.4%), snoring (8.9%), and restlessness (7%) (Fig. 2).

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Discussion

The findings of this study indicate a clear association between smartphone ST and sleep quality among MBBS students. As expected, students with higher ST—particularly those exceeding 2 hours per day—reported poorer sleep quality. This finding aligns with previous research suggesting that prolonged exposure to blue light emitted by screens delays the secretion of melatonin, leading to sleep onset difficulties and fragmented sleep. Additionally, the temptation to use social media, messaging apps, and other forms of digital entertainment late into the night can contribute to sleep procrastination, further shortening sleep duration and reducing sleep quality.

Another noteworthy finding is the difference in ST and sleep patterns according to the academic year. First-year students, who typically have fewer academic responsibilities, reported the lowest average ST and better sleep quality compared to their third-year counterparts. Third-year students, on the other hand, face increased academic and clinical demands, which may explain their higher ST and poorer sleep quality. This suggests that academic stress and workload contribute not only to increased ST and sleep disturbances.

Interestingly, although males reported higher average STs than females, the difference in sleep quality between genders was not statistically significant. This may be due to different coping mechanisms for academic stress, with female students perhaps more likely to engage in activities that improve their sleep quality, such as physical exercise and mindfulness practices.

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Conclusion

This study demonstrated a significant relationship between smartphone ST and sleep quality among MBBS students at the Government Medical College, Kottayam. A substantial proportion of students, particularly those in their third year, reported high ST and poor sleep quality, indicating a need for increased awareness of the negative health effects of excessive smartphone use.

Medical students are particularly vulnerable to sleep disturbances because of their rigorous schedules and academic demands. Poor sleep quality not only affects cognitive performance and learning but also increases the risk of mental health issues, such as anxiety and depression.

Reducing ST, particularly before bedtime, can be an effective strategy for improving sleep quality. Students should be encouraged to adopt healthier sleep hygiene practices, such as setting limits on screen use, engaging in relaxation techniques, and creating a sleep-conducive environment. Colleges and universities can play a crucial role by providing resources and workshops on the importance of sleep and the dangers of excessive screen exposure.

In conclusion, excessive smartphone ST is a growing public health concern that requires immediate attention, especially among students. By promoting healthier digital habits and sleep hygiene, educational institutions can help students achieve better sleep quality and, in turn, improve their overall well-being and academic success.

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Acknowledgment

The authors express their sincere thanks to the MBBS students of the Government Medical College Kottayam, for their co-operation, patience, and support during data collection. Furthermore, the authors express their thanks to the head of the Department of Physiology for giving permission to conduct the study in the department.

Conflict of interest

Nil.

Funding

Nil.

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