Received: October 25, 2015; Accepted: April 06, 2016. Iran J Med Phys., Vol. 13, No. ... business applications, and Internet access for the users. Most of the ...
Iranian Journal of Medical Physics Vol. 13, No. 1, March 2016, 8-16 Received: October 25, 2015; Accepted: April 06, 2016
Original Article
The Correlation between Cell Phone Use and Sleep Quality in Medical Students Mohamad Reza Bayatiani1, Fatemeh Seif1*, Akram Bayati2
Abstract Introduction The negative health effects of electromagnetic radiation and psychological dependence are among the major consequences of widespread cell phone use in the general population, especially among adolescents. In this study, the relationship between cell phone use and sleep quality parameters was evaluated. Materials and Methods The study sample consisted of 820 students (305 males and 515 females), recruited from Arak University of Medical Sciences, Arak, Iran. The participants completed Pittsburgh Sleep Quality Index (PSQI) and Cellphone Overuse Scale (COS); the validity of these questionnaires had been previously confirmed in the Iranian population. Information on demographic characteristics and variables associated with cell phone exposure, such as the frequency and duration of phone calls and number of messages was collected in a separate questionnaire. Results Data analysis showed that cell phone overuse was significantly correlated with sleep quality and its components. Moreover, the results indicated that the global PSQI score and some sleep components were significantly correlated with several variables related to cell phone use. Based on the findings, the mean PSQI score was significantly different among heavy and light cell phone users (P 5). PSQI score > 5 was reported in 56.7% of males versus 62.5% of females; the difference was statistically significant (P=0.001). As presented in Table 2, history of cell phone possession was not significantly correlated with the global PSQI score or some components of the scale. Although there was a significant correlation between the frequency of phone calls (made and received) and some components of PSQI, the global PSQI score was not significantly correlated with this variable. According to the findings, the global PSQI score showed a positive significant correlation with the duration of each phone call and PSQI components, except for daytime dysfunction. With the exemption of sleep disturbance, other components of PSQI and the global PSQI score had a positive significant correlation with the frequency of text messaging (including text messages exchanged by cell phone operators, while excluding social network messaging). Based on the results, distance of the cell phone from the head had a negative correlation with the global PSQI score and some of the scale components during night sleep. Moreover, among cell phone-related variables, spending time on the Internet via cell phone had a more significant positive correlation with global PSQI score, based on Spearman's correlation test (r=0.262; P60 Distance of cell phone from the head in the bed (cm) 5-10 10-20 20-30 >30 Off
11
Male N=305 Freq. %
Female N=515 Freq. %
13 34 133 87 38
4.3 11.1 43.6 28.5 12.5
27 145 228 115 0
5.2 28.2 44.3 22.3 0
87 131 41 46
28.5 43 13.4 15.1
107 352 26 30
20.8 68.3 5 5.8
208 41 15 16 25
68.2 13.4 4.9 5.2 8.2
273 127 44 45 26
53 24.7 8.5 8.7 5
44 72 56 133
14.4 23.6 18.4 43.6
103 122 52 238
20 23.7 10.1 46.2
47 7 26 18 21 187
15.4 2.3 8.5 5.9 6.6 61.3
52 40 27 30 19 347
10.1 7.8 5.2 5.8 3.7 67.4
44 102 76 38 45
14.4 33.4 24.9 12.5 14.8
99 157 153 42 64
19.2 30.4 29.7 8.1 12.4
Iran J Med Phys., Vol. 13, No. 1, March 2016
Mohamad Reza Bayatiani et al.
Table 2. Correlation between PSQI scores and cell phone-related variables
Mean duration of each call
Number of text messages (made and received)
Distance of cell phone from the head in the bed
Spending time on the Internet via cell phone
COS
History of cell phone possession
Frequency of phone calls (made and received)
Male
Female
Total
PSQI
-0.053
0.058
0.176**
0.218**
-0.232**
0.262**
0.25**
0.428**
0.354**
Sleep quality
0.049
0.113**
0.126**
0.22**
-0.052
0.159**
0.039
0.418**
0.284**
0.003
-0.075*
0.21**
0.169**
-0.205**
0.088*
0.144*
0.276**
0.214**
-0.052
0.103**
0.141**
0.125**
-0.177**
0.029**
0.262**
0.203**
0.217**
0.031
0.061
0.070*
0.139**
-0.018
0.198**
-.036
0.286**
0.168**
-0.063
-0.137**
0.124**
0.047
-0.125**
0.007
0.201**
0.217**
0.204**
-0.023
0.052
0.087*
0.123**
-0.051
0.051
0.189**
0.284**
0.250**
0.025
0.087*
-0.016
0.11**
0.132*
0.323**
0.246**
Sleep latency Sleep duration Sleep efficiency Sleep disturbance Use of sleep medication
Daytime -0.046 -0.007 dysfunction *Significant correlation at 0.05 **Significant correlation at 0.01
Table 3. Comparison between light and heavy cell phone users in terms of the global PSQI score and its components
PSQI
Sleep quality
Sleep latency
Sleep duration
Sleep efficiency
Sleep disturbance Use
of
sleep
medication Daytime dysfunction
Type of use
Mean
SD
Light cell phone users
5.28
0.188
Heavy cell phone users
8.53
2.77
Light cell phone users
0.99
0.70
Heavy cell phone users
1.41
0.67
Light cell phone users
0.95
0.99
Heavy cell phone users
1.51
0.96
Light cell phone users
1.21
0.76
Heavy cell phone users
1.76
1.28
Light cell phone users
0.57
0.45
Heavy cell phone users
0.18
0.92
Light cell phone users
0.96
0.44
Heavy cell phone users
1.33
0.67
Light cell phone users
0.00
0.00
Heavy cell phone users
0.38
0.72
Light cell phone users
1.00
0.69
Heavy cell phone users
1.54
0.94
Iran J Med Phys., Vol. 13, No. 1, March 2016
P-value
0.05
7.5±3.2
9.4±3.9
