Effect of smartphone screen time on sleep quality and daytime alertness: A cross-sectional observational study.

Dr. Amrutha  Kanagala; Dr. Ankur

doi:10.51168/sjhrafrica.v7i3.2379

Authors

Dr. Amrutha Kanagala Associate Professor, Department of Physiology, Mamata Medical College, Khammam, Telangana, India
Dr. Ankur Professor, Department of Physiology, Rohilkhand Medical College and Hospital, Bareilly, Uttar Pradesh, India

DOI:

https://doi.org/10.51168/sjhrafrica.v7i3.2379

Keywords:

Smartphone, Screen time, Sleep quality, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Daytime sleepiness, Young adults

Abstract

Background:

Smartphone use is pervasive in young adults and frequently extends into the pre-sleep period. Prolonged and late-night screen exposure can disrupt sleep initiation and continuity and contribute to next-day sleepiness.

Objectives:

To evaluate the association between daily smartphone screen time, sleep quality, and daytime alertness among young adults.

Methods:

This observational study was conducted among 100 adults at the Department of Physiology, Mamata Medical College, Khammam, Telangana, India, between January and December 2025. Daily screen time and bedtime phone-use behaviors were recorded. Sleep quality and daytime sleepiness were assessed using standardized questionnaires. Associations were examined across screen-time categories, along with correlation and multivariable analyses.

Results:

The mean age was 22.9 ± 3.8 years, and 54.0% were female. Mean smartphone screen time was 5.1 ± 2.0 hours/day; 76.0% used phones within 1 hour before sleep, and 41.0% frequently used them in bed. Mean PSQI rose from 4.6 ± 1.9 in those with <3 hours/day screen time to 8.3 ± 2.6 in those with >7 hours/day. Poor sleep increased from 30.0% to 100.0%, and short sleep from 35.0% to 82.4% [p < 0.001]. Mean ESS was 9.6 ± 3.8; screen time correlated with PSQI [r = 0.49] and ESS [r = 0.36], independently predicting poor sleep and daytime sleepiness significantly.

Conclusion:

Higher daily smartphone screen time and near-bedtime use were associated with poorer sleep quality and reduced daytime alertness in young adults. Targeted sleep-hygiene counselling focused on screen-time timing and duration is warranted in college and workplace health programs.

Recommendations:

Practical steps include keeping the phone away from the bed, stopping screen use at least 60 minutes before sleep, enabling night-mode settings, and replacing late-night scrolling with a low-stimulation wind-down routine.

Author Biographies

Dr. Amrutha Kanagala, Associate Professor, Department of Physiology, Mamata Medical College, Khammam, Telangana, India

is an Associate Professor in the Department of Physiology at Mamata Medical College, Khammam, Telangana, India. She is actively involved in undergraduate and postgraduate teaching and contributes to competency-based medical education through academic mentoring and curriculum development. Her research interests span cardiovascular physiology, metabolic regulation, and applied clinical physiology, with a focus on translating basic physiological principles into clinical relevance. She has participated in institutional research projects and academic initiatives aimed at strengthening evidence-based medical education. ORCID iD: https://orcid.org/0009-0004-8413-2859

Dr. Ankur, Professor, Department of Physiology, Rohilkhand Medical College and Hospital, Bareilly, Uttar Pradesh, India

is a Professor in the Department of Physiology at Rohilkhand Medical College and Hospital, Bareilly, Uttar Pradesh, India. He has extensive experience in teaching physiology to undergraduate and postgraduate medical students and is actively engaged in academic administration and curriculum planning. His academic interests include cardiovascular and respiratory physiology, integrative human physiology, and medical education research. He has guided student research projects and contributes to institutional academic and faculty development activities, with a sustained focus on strengthening conceptual learning and clinical application of physiological principles.

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