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VOLUME-CİLT 5 NUMBER-SAYI 1 / 2018 THE JOURNAL OF NEUROBEHAVIORAL SCIENCES 13
JNBS 2018 Published by Üsküdar University / 2018 Üsküdar Üniversitesi tarafından yayımlanmaktadır www.jnbs.org
ORIGINAL ARTICLE-ARAŞTIRMA
1Milli Savunma Bakanlığı, Ankara, Türkiye
2 Ministry of Health Gulhane Education Research Hospital Ankara, Turkey
*Corresponding author: Duygu Akçay, Milli Savunma Bakanlığı, Ankara, Türkiye, E-mail: dakcay2010@hotmail.com
Özet
Adölesanlarda cep telefonu kullanımının uyku kalitesi üzerine etkisini değerlendirilmek amaçlanmıştır. Bu tanımlayıcı araştırma, Konya
Lisesinde kayıtlı 9., 10. ve 11. sınıf öğrencileri (n=380, %51.6’sı Bayan, yaş aralığı 16.05±0.87) üzerinde, 13-15 Ocak 2016 tarihleri
arasında yapılmıştır. Öğrencilerin uyku kalitelerini ölçmek amacıyla Pitsburg Uyku Kalitesi Ölçeği (PUKİ) kullanılmıştır. Öğrenciler ilk
cep telefonları ortalama 12.29±1.41 yaşında almıştır. Adölesanların cep telefonunu günlük ortalama 3.03±2.18 saat kullandıkları ve en
çok mesajlaşmak (%89.5) için kullandığı belirlenmiştir. Ortalama uyuma saati ertesi gün okul yoksa 7.34±1.22 saat, ertesi gün okul
varsa 9.11±1.79 saat olarak belirlenmiştir. Öğrencilerin cep telefonu kullanma süresi arttıkça uyku kalitesinin düştüğü belirlenmiştir
(p<0.01). PUKİ ölçeğine göre uyku kalitesi iyi olan öğrencilerin %20.5’inin, kötü olanların ise %79.5’inin cep telefonu ile meşgul
olduğu zaman yatma zamanını ertelediği belirlenmiştir (p<0.05). Cep telefonları adölesanların yatak odalarından çıkarılmalıdır. Aileler
çocuklarının cep telefonu kullanımını, içeriğini kontrol etmelidirler.
Anahtar Kelimeler: adölesan, uyku kalitesi, cep telefonu, uyku rutini
Abstract
To evaluate the effect of mobile phone usage on adolescents’ sleep quality. This descriptive study took place from January 13-
15, 2016 with 9th, 10th, and 11th grade students enrolled at Konya High School (n=380, 51.6% female, age 16.05±0.87). A
questionnaire was used for data collection and the Pittsburgh Sleep Quality Index (PSQI) was used to measure the sleep quality
of the students. Students received their first mobile phones at an average age of 12.29±1.41). They used their phones 3.03±2.18
hours per day on average, mostly for text messaging (89.5%). Average sleeping time was 7.34±1.22 hours when the next day was
not a school day, and 9.11±1.79 hours when the next day was a school day. Sleep quality of the students decreased as the duration
of mobile phone usage increased (p<0.01). Using the PSQI scale, it was determined that 20.5% of the students with good sleep
quality and 79.5% of the students with poor sleep quality delayed their bedtime in favor of continued usage of their phone (p<0.05).
Mobile phones should be removed from the bedrooms of adolescents. Parents should control their children’s mobile phone usage
and contents.
Keywords: adolescent, sleep quality, mobile phone, sleep routine.
THE EFFECT OF MOBILE PHONE USAGE ON SLEEP QUALITY
IN ADOLESCENTS
ADÖLESANLARDA CEP TELEFONU KULLANIMININ UYKU KALİTESİ
ÜZERİNE ETKİSİ
Year (Yıl) : 2018
Volume (Cilt) : 5
Issue Number (Sayı) : 1
Doi : 10.5455/JNBS.1519129764
Received/Geliş: 20.02.2018
Accepted/Kabul:19.03.2018
Duygu Akçay1*, Bülent Devrim Akçay2
14 THE JOURNAL OF NEUROBEHAVIORAL SCIENCES VOLUME-CİLT 5 / NUMBER-SAYI 1 / 2018
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SCIENCES
NÖRODAVRANIŞ BİLİMLERİ DERGİSİ
JNBS 2018 Published by Üsküdar University / 2018 Üsküdar Üniversitesi tarafından yayımlanmaktadır www.jnbs.org
ORIGINAL ARTICLE-ARAŞTIRMA
and with the 1964 Helsinki Declaration and its later
amendments or comparable ethical standards.
2.2. Instruments
Introductory Characteristics of the Students and Status of
Mobile Phone Use Habits Information Form:
This form was created by the researcher for the purpose
of gathering information related to the variables that had
been determined to have an impact, according to a review
of the relevant literature, on the children constituting the
study sample (Arora et al., 2014; Bartel et al., 2015; Bruni
et al., 2015; Cain & Gradisar, 2010; Demirci et al., 2015;
Eyvazlou et al., 2016; Hale & Guan, 2015; Mohammadbeigi
et al., 2016; Sahin et al., 2013; Mak et al., 2014; Yogesh et
al., 2014).
Pittsburgh Sleep Quality Index (PSQI): The PSQI was
developed by Buysse et al. and adapted to Turkish by
Ağargün et al. (1996) The PSQI is a 19-item self-report
index that assesses sleep quality and disturbances over
the responder’s past month. It consists of 24 questions,
including 19 self-report questions and 5 questions to be
answered by spouse or roommate. The 24 questions of
the index that are scored consist of 7 components. Each
component is assigned a value of 0-3 points. The total score
of the 7 components gives the total score of the index, which
ranges from 0 to 21. A total score higher than 5 indicates
poor sleep quality. The spouse/roommate section was not
used in this study since it was conducted on adolescents.
2.3. Statistical Data
The data obtained from the study was evaluated using the
SPSS 15.0 program. Daily mobile phone usage times were
calculated as (weekday duration x5 + weekend duration
x2)/7. To analyze student demographics and telephone
usage habits, the bivariate Pearson correlation was used to
identify the relationships between frequency, percentage
retrieval techniques, frequency of cell phone use, and
some sleep variables with PSQI. An independent two-group
difference test (t-test) and a Chi-square test were applied to
test the relationship between the postponement of bedtime
and PSQI.
3. Results
The average age that the students received their rst mobile
phone was 12.29 ± 1.41. The students reported using their
mobile phones 3.03 ± 2.18 hours a day on average. Some
students (30.8%) reported many times daily phone usage,
and most (57.1%) used their mobile phone many times a
day. Most of the students (89.5%) used their mobile phones
for messaging (Table 1). Students usually had a 23.34 ±
1.08 bedtime and 7.27 ± 1.30 wake up time. The average
sleep duration was 7.35 ± 1.20 hours if there was no school
the next day, and 9.15 ±1.66 hours if there was school the
next day. The average score for total PSQI was 7.04 ± 3.36.
According to these PSQI scores, 65.5% of the adolescents
participating in the study had poor quality sleep.
1. Introduction
Sleep is a basic necessity that constitutes almost one-
third of the hours in a human’s lifetime. It is a state of
reversible unconsciousness, where the body and mind are
renewed, repaired, and developed (Karadağ, 2017). Sleep
is a cornerstone of adolescent development. Although
sleep duration varies, 8-10 hours per night is sufcient
for adolescents (Hirshkowitz et al., 2015). Electronic
media has a negative effect on the sleep of children and
adolescents (Cain & Gradisar, 2010; Hale & Guan, 2015).
Though the media has begun to form an important
part of the daily life of young people, the increasing
frequency of use of media such as television (TV),
computer games, Internet, mobile phone usage threatens
healthy sleep. Using the media can change the sleeping
time and shorten the sleeping period. Media content can
cause extreme excitement or cause recurring voyages
(Van den Bulck 2010). Research shows that there is a
relationship between mobile phone usage and sleep quality
(Bruni et al., 2015; Demirci et al., 2015; Eyvazlou et al.,
2016; Mohammadbeigi et al., 2016; Sahin et al., 2013;
Yogesh et al., 2014). In other studies on adolescents, it
has been found that the use of telephone delayed (Bartel
et al., 2015), the sleeping time, making sleeping difcult
(Arora et al., 2014), which affects the sleeping negatively
(shortening the duration of sleep) (Hale & Guan, 2015).
In another research conducted on the subject, it has been
determined that despite the frequent use of television
and computer, it is not related to sleep variables, whereas
mobile phone use is associated with all sleep variables
(Mak et al., 2014). Mobile phones are widely used among
young people, and the effect of this habit on their sleep
quality is not well-known. This study was conducted to
evaluate the effect of mobile phone usage on adolescents’
sleep quality.
2. Materials And Methods
2.1. Participants and Procedure
This descriptive study research was conducted January
13-15, 2016. The study population was 9th, 10th, and
11th grade students (n = 982) at Konya High School
during the 2015-2016 school year. Students who reported
that they had a mobile phone and did not have any
psychological, neurological, or respiratory sleep problems
were included in the survey. A total of 380 students (age
16.05±0.87) voluntarily participated in the study. A
questionnaire for data collection was developed to obtain
demographic information and mobile phone usage habits
of the students, and the Pittsburgh Sleep Quality Index
(PSQI) was used to measure the students’ sleep qualities.
Institutional approval was granted from the Konya
Provincial Directorate for National Education, and the
ethical approval, with the decision number of 2016/2
dated January 12, 2016, was obtained from the Konya
Selçuk University Ethics Committee. Informed consent
was obtained from all participants and their parents.
All procedures performed in this study involving human
participants were in accordance with the ethical standards
VOLUME-CİLT 5 NUMBER-SAYI 1 / 2018 THE JOURNAL OF NEUROBEHAVIORAL SCIENCES 15
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ORIGINAL ARTICLE-ARAŞTIRMA
Table 2. Relationship Between Mobile Phone Usage
Time and Some Sleep Variables and PSQI
The duration of mobile phone use was 2.48 ± 1.70 hours
for the students whose sleep time was sufcient, and 3.60
± 2.45 hours for those whose sleep time was insufcient
(p<0.001). The duration of mobile phone usage by
students who kept their phone near them while sleeping
was 3.52 ± 2.48 hours, and it was 2.68 ± 1.85 hours for
those who did not keep their phone nearby (p<0.001).
There was a positive correlation (r = .165, p <0.01)
between the duration of mobile phone use and the total
PSQI score of the students (Table 2).
Table 3. Sleep Routine Distribution of the Research
Group
The adolescents in the study group most often delayed
their bedtime due to studying (73.7%), reading (35%),
and using their mobile phone (19.2% ) (Table 3).
Table 4. Relationship Between Bedtime Delay and PSQI
in the Study Group
According to the PSQI scale, 20.5% of the students with
good sleep quality and 79.5% of students with poor sleep
quality delayed their bedtime due to mobile phone usage.
This difference was statistically signicant (p<0.05)
(Table 4). All of the reasons for delaying sleeping time in
Table 3 were compared with the PSQI scale and the only
statistically signicant difference was with “when busy
with mobile phone”.
Mobile Phone Usage Time
Significance*
n x ± sd
Sleep time
sufficiency
Sufficient 193 2.48 ± 1.70 0.000
p<0.001
Insufficient 187 3.60 ± 2.45
Mobile phone
available and
close by while
sleeping
Yes 159 3.52 ± 2.48 0.000
p<0.001
No 221 2.68 ± 1.85
Min/Max x ± sd r Significance**
Total PSQI 1/18 7.04 ±
3.36 0.165 0.001
p< 0.01
Sleep Routines*
Reasons For Delaying Bedtime
n %
Studying 280 73.7
Reading 133 35.0
Using a mobile phone (playing
games, speaking, messaging,
etc.)
73 19.2
Social networking 69 18.2
Internet use 67 17.6
Watching TV or DVDs 65 17.1
Playing games with computers,
game consoles, etc.
60 15.8
Studying with computers 47 12.4
Listening to music 41 10.8
Other (taking a bath, etc.) 28 7.4
Directly going to bed 16 4.2
Sleeping Time Delay Due to Mobile Phone Use
PSQI Yes No Significance*
n % n %
Good 15 20.5 116 37.8 0.005
p<0.05
Poor 58 79.5 191 62.2
Total 73 100 307 100
Table 1. Descriptive Characteristics of the Study Group
Gender n %
Female 196 51.6
Male 184 48.4
Family Income Status n %
Low 14 3.7
Middle 185 48.7
Good 168 44.2
High 13 3.4
Family Structure n %
Nuclear 334 87.9
Broad 37 9.7
Broken 9 2.4
Thinking About Using a Phone Too Much n %
Yes 117 30.8
No 263 69.2
Frequency of Mobile Phone Usage n %
Every hour 72 18.9
Many times in an hour 37 9.7
Once daily 54 14.2
Many times daily 217 57.1
Use of the Mobile Phone* n %
Messaging 340 89.5
Speaking to family 311 81.8
Speaking to friends 288 75.8
Reading news 279 73.4
Going online, researching, solving problems. 245 64.5
Entering social networking sites 245 64.5
Playing games 150 39.5
Listening to music 124 32.6
*Multiple choices were permitted.
*Independent Samples t Test
**Bivariate Pearson Correlation
*Chi-square Test
16 THE JOURNAL OF NEUROBEHAVIORAL SCIENCES VOLUME-CİLT 5 / NUMBER-SAYI 1 / 2018
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JNBS 2018 Published by Üsküdar University / 2018 Üsküdar Üniversitesi tarafından yayımlanmaktadır www.jnbs.org
4. Discussion
In this study, 57.1% of students with mobile phones
used them many times a day and their rst mobile phone
was bought for them at age 12.29 ± 1.41 on average.
They spent 3.03 ± 2.18 hours on them daily, on average.
In a study of adolescents in Japan, it was found that only
31.42% of the students had a mobile phone and they
used the mobile phone in speaking mode for an average
of 7.08 ± 21.42 minutes a day (Mortazavi et al., 2011).
Another study by Munezawa et al. (2011) found that
84.4% of students use a mobile phone, even if only
for a short time each day. In a survey conducted on
adolescents, the average daily phone use of participants
was 131.77 ± 119.9 minutes (Nikhita et al., 2015). In a
study conducted by Mak et al. (2014), participants used
mobile phones an average of 2.31 ± 3.74 hours a day. A
study of university students in Turkey found that 28.3%
of students acquired their rst mobile phone at age 13
or younger, and they used them for more than ve hours
a day (Sahin et al., 2013). These results show that the
mobile phone is one of the electronic media products
most frequently used by adolescents. Today, young
people socialize with their peers through technology,
especially mobile phones. Mobile phones bring the ability
to go online, transfer mobile data, playback music, record
video, take pictures, and keep a calendar, while being
portable. In this study, the increased frequency of mobile
phone usage may be due to developmental factors of the
adolescents or the increased social interaction. Young
people may be using mobile phones because they see
socialization and technological connection as a means of
liberation, fashion, and social status indication.
In this study, 89.5% of adolescents used mobile phones
for messaging and 81.8% used them to talk to their
families. A survey conducted in India found that 94.2% of
participants used their mobile phone to make calls (Stalin
et al., 2016). Another survey found that 33.5% of students
use mobile phones for messaging, and 28.5% use them
for speaking to their families (Sahin et al., 2013). A study
conducted by Charles Sturt University found that 55% of
students prefer text messaging (SMS), while prefer 30%
to speak (Carroll, 2005). Our study is similar to other study
ndings. Young people use mobile phones for purposes
other than communication, which is the main function of
the phone. Young people may prefer to communicate via
SMS because it enables them to communicate as they
are available and allows them to respond more quickly in
everyday life and social relationships.
The students usually had a 23.34 ± 1.08 bedtime and
7.27 ± 1.30 wake up time. The average sleep duration
was 7.35 ± 1.20 hours if there was no school next day,
and 9.15 ± 1.66 hours if there was school the next day.
In a study by Mak et al. (2014), the participants slept an
average of 7.74 ± 1.46 hours per night. In another study
conducted on adolescents, participants slept an average
of 8.06 hours on weekdays and 9.30 hours on weekends
(Gamble et al., 2016). Adolescents are not recommended
to sleep more than 11 or less than 7 hours per night
(Hirshkowitz et al., 2015). In the study group, although
better on school nights, the sleep duration was at the
lower end of the recommendation. The participants were
careful not to allow lack of sleep to affect their daytime
activities and performances by choosing to go to sleep
earlier on school nights.
Students who slept next to their mobile phones and
whose sleep period was considered inadequate had
increased mobile phone usage times. According to PSQI
scores, 65.5% of participants had poor quality sleep. The
sleep quality of the students decreased as the duration
of mobile phone usage increased. Mortazavi et al. (2011)
determined a statistically signicant relationship between
the number of sleeping problems and the amount of
time they used mobile phones for speaking. Another
study among adolescents in Sweden found that the
prevalence of sleep impairment is higher among people
who use the mobile phone frequently (Thomée et al.
2011). Surveys on university students have found that
sleep quality decreased as mobile phone dependency
increased (Demirci et al., 2015; Sahin et al., 2013). In
similar studies, there was a relationship between mobile
phone use and sleep quality (Bruni et al., 2015; Eyvazlou
et al., 2016; Mohammadbeigi et al., 2016; Yogesh et al.,
2014). It was not possible to correlate the deterioration
of the participants’ sleep quality solely to mobile phone
use. However, it was shown that excessive use of mobile
phones affects sleep quality. Keeping mobile phones
away from sleeping adolescents would be a method for
reducing mobile phone usage that would cause minimal
interference. It has been anticipated that it would be
useful to conduct training and intervention studies about
the arrangement of sleep pattern and media literacy in
the study group in the future term. Adolescents should be
directed to activities where they will spend quality time
(e.g., sports, creative and social games, etc.).
The relationship between the adolescents’ bedtime
delay and their rank on the PSQI scale was statistically
signicant. In a meta-analysis of forty studies, phone use
was found to delay bedtime in adolescents (Bartel et al.,
2015). In a large participatory study of adolescents in
Norway, 80% of females and 90% of males used their
mobile phone an hour before bedtime, and this reduced
sleep duration by two hours or more (Hysing et al.,
2015). Munezawa et al. (2011) reported in their survey
of Japanese adolescents, that every day, after turning off
the lights, the participants used their mobile phones 8.3%
to call and 17.6% to send messages. In the same study,
sleep disturbances (short sleep duration, subjective sleep
quality, daytime extreme sleepiness, and insomnia) were
found in people who use their mobile phones to talk
and send messages after the lights are turned off. In a
study by Zarghami et al. (2015), there was a signicant
relationship between sleeplessness and mobile phone use
late at night. In a study by Gamble et al. (2014), there
was a relationship between the long-term use of mobile
phones and delayed sleeping and waking. In a study by
Fobian et al. (2016), there was a negative correlation
between sleep efciency and both daytime messaging and
the number of nightly awakenings by mobile phone. The
current study is similar to other study ndings, in that the
use of the phones causes sleep quality to deteriorate as a
result of delaying bedtime in adolescents. Students that
had their mobile phones near them while sleeping saw an
ORIGINAL ARTICLE-ARAŞTIRMA
VOLUME-CİLT 5 NUMBER-SAYI 1 / 2018 THE JOURNAL OF NEUROBEHAVIORAL SCIENCES 17
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ORIGINAL ARTICLE-ARAŞTIRMA
increased duration of mobile phone usage. As a result,
adolescents are preoccupied with their phones before
bed and it is inevitable that both sleeping and waking
are delayed and sleep quality is affected. Sleep, which is
a basic element in physical growth and in strengthening
academic performance, must be adequate. Signicant
changes are needed in the habits of adolescents in the
study group.
Among the limitations of the research, the sample size
was small. However, as the number of research studies
conducted in this country are few, the results remain
important to raise awareness of this issue.
5. Conclusions
Sleep quality decreases as the duration of mobile phone
usage increases. Young people prefer mobile phones over
other media products because mobile phones are portable
and include almost all the features and capabilities of
other media products. The length of time adolescents
spend with their mobile phone is a matter of concern for
adolescents, and the use of mobile phones by children
can cause health bad effects. Adolescents should make
changes to regulate their sleep patterns. Mobile phones
should be removed from the bedrooms of adolescents.
Families should control their children’s intended use of
mobile phone and its content and should limit the time
spent with them.
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