Computer/Mobile Device Screen Time of Children and Their Eye Care Behavior: The Roles of Risk Perception and Parenting

Abstract

This study assessed the computer/mobile device screen time and eye care behavior of children and examined the roles of risk perception and parental practices. Data were obtained from a sample of 2,454 child-parent dyads recruited from 30 primary schools in Taipei city and New Taipei city, Taiwan, in 2016. Self-administered questionnaires were collected from students and parents. Fifth-grade students spend more time on new media (computer/smartphone/tablet: 16 hours a week) than on traditional media (television: 10 hours a week). The average daily screen time (3.5 hours) for these children exceeded the American Academy of Pediatrics recommendations (≤2 hours). Multivariate analysis results showed that after controlling for demographic factors, the parents with higher levels of risk perception and parental efficacy were more likely to mediate their child's eye care behavior. Children who reported lower academic performance, who were from non-intact families, reported lower levels of risk perception of mobile device use, had parents who spent more time using computers and mobile devices, and had lower levels of parental mediation were more likely to spend more time using computers and mobile devices; whereas children who reported higher academic performance, higher levels of risk perception, and higher levels of parental mediation were more likely to engage in higher levels of eye care behavior. Risk perception by children and parental practices are associated with the amount of screen time that children regularly engage in and their level of eye care behavior.

Introduction

In this digital age, children spend more time with new media (computers, tablets and smartphones) than with traditional media (television [TV], printed publications, and radio).¹ Studies conducted in several countries have indicated that more than two-thirds of children exceed the screen time recommendations (≤2 hours/day) issued by the American Academy of Pediatrics.^1–3 Studies show that longer screen times for children are associated with insufficient physical activity,⁴ warning signs that include overweight and obesity,⁵ unhealthy dietary habits,⁶ metabolic syndrome,⁷ lower levels of sleep quality,^8,9 mental illness (anxiety, depression),¹⁰ and behavior problems (conduct problems, peer problems).¹¹

In addition, studies show that increasing exposure to computers and mobile devices has a negative impact on ocular health.^12,13 Computer-vision syndrome has become more prevalent among both adolescents and adults.¹⁴ A study conducted in Malaysia indicated that 90 percent of the university students tested had symptoms of computer-vision syndrome,¹⁵ which include eyestrain, headache, fatigue, burning sensations, watering, and redness.¹⁶ Children are more susceptible than adults to developing eye and vision problems.¹⁷ Smartphone use by children has been associated with pediatric dry eye diseases.^18,19 About four-fifths of 12th-grade students in Taiwan develop myopia, whereas one-fifth of the myopic population have high myopia that may result in the causes of irreversible vision loss such as retinal detachment, choroidal neovascularization, cataracts, glaucoma, and macular atrophy.²⁰

The family can be an important influence with respect to a child's screen time and with the establishment of preventive behaviors. Study results indicate that clear rules and setting limits on screen time are negatively associated with a child's screen time, whereas having screen media in the bedroom is positively associated with screen time.^4,21–23 In addition, parental modeling is crucial in influencing a child's screen time.²⁴ Study results show that parental TV viewing and computer/game-use habits are related to a higher level of engagement in these screen activities by children.^25,26

Eye and vision health problems are crucial issues in Taiwan. One-third of second-grade students in Taipei suffer from myopia.²⁷ The risk factors for myopia include time spent on near-work activity every day, shorter visual distances during near-work activity, and participation in after-school tutorial programs. Protective factors include resting after 30 minutes of near-work activity and spending more time participating in outdoor activities.²⁷ As more people own and use mobile devices in Taiwan, children from disadvantaged families may be more vulnerable to cyber and health risks due to the digital divide in Internet literacy and parental mediation.²⁸ Very few studies have examined parental mediation and child eye care behavior. This study was focused on assessing the computer/mobile device screen time and eye care behavior of children. The Extended Parallel Process Model (EPPM)²⁹ concept was applied to examining the relationships of risk perception, parental efficacy, parental practices, the screen time of children, and eye care behaviors.

Materials and Methods

Participants and procedures

In 2015, a total of 118,471 students attended 151 primary schools in Taipei City, whereas 201,970 students attended 216 primary schools in New Taipei City, Taiwan. Based on the sampling frame, which was a list of schools and their student enrollments, a probability-proportionate-to-size sampling method was used to systematically draw a random sample of schools. A total of 47 schools were invited to join the survey, and 17 schools in Taipei city along with 13 schools in New Taipei City agreed to participate. Three to five classes were randomly selected from each sample school. Approval was obtained from the Institutional Review Board at National Taiwan Normal University.

After class selection, teachers gave students consent forms to take home to parents requesting consent for them and their children to participate in the survey. The children also filled out a consent form to indicate their willingness to participate in this study. After the consent forms were collected, researchers visited the schools to conduct a self-administered survey. Questionnaires for Parents were delivered to students in their classrooms to take home. A total of 1,087 and 1,534 fifth-grade students (aged 10–11 years old) in Taipei city and New Taipei City, respectively, completed the Child Questionnaire; whereas 1,088 and 1,380 parents in Taipei city and New Taipei city, respectively, returned a completed Parent Questionnaire. About one-seventh of children and one-fifth of parents declined to participate in this study. The response rate was 86 percent for children and 79 percent for parents. The codes for the Child and Parent Questionnaires were matched. This study excluded 31 and 44 Taipei city and New Taipei city parent questionnaires, respectively, because grandparents or other family relatives had completed them.

Instrument

The self-administered questionnaire was developed based on previous studies such as the Net Children Go mobile,³⁰ EU Kids online,³¹ and the U.S. Youth Internet Safety Surveys.^32,33 A group of eight experts were invited to assess the content validity of the questionnaire. Experts reviewed the draft questionnaire and provided comments and suggestions for improvement. In addition, a pilot survey was conducted at two schools that were not included in the sample schools to examine the students' responses to the survey and to evaluate the reliability of the data that the questionnaire would yield.

Screen time

Children and parents were asked the time per week spent viewing TV, computers, smartphones, and tablets. Each media weekly use time was calculated from two questions. (1) During the past week, how much time did you spend watching TV, using a computer, using a smartphone, or using a tablet per weekday (Monday to Friday)? The response options included the following: “0 min,” “1–29 min,” “30–59 min,” “1 hour/less than 2 hours,” “2 hours/less than 3 hours,” and “3 hours or more.” (2) During the past week, how much time did you spend watching TV, using a computer, using a smartphone, or using a tablet per weekend day (Saturday and Sunday)? The response options included the following: “less than 1 hour,” “1 hour/less than 2 hours,” “2 hours/less than 3 hours,” and “3 hours or more.” Computer/mobile device screen time refers to the sum of weekly use hours spent on computers, smartphones, and tablets.

Eye care behavior of children

Six items were used to measure the eye care behavior of children. Children were asked how often they had implemented the following behaviors when using computers, smartphones, or tablets during the past week. Sample statements were “I use computers, smartphones, or tablets for 30 minutes then take a break for 10 minutes”; “I use computers, smartphones, or tablets with good position without leaning on a table”; “I use computers, smartphones, or tablets at a distance of at least 35 cm”; and “I use computers, smartphones, or tablets in a room with good lighting.” Each item was evaluated by using a 5-point Likert-type scale from “always” (scoring 5) to “never” (scoring 1). A higher score indicated a higher level of eye care behavior. The Cronbach's alpha for eye care behavior by these children was 0.68.

Parental mediation of the eye care behavior of children

Parental mediation of the eye care behavior of children was measured with 7 items. Sample statements included “I ask my child to take a break of 10 minutes for every 30 minutes of computer, smartphone, or tablet use”; “I ask my child to have proper position and not lie on the table when using computers, smartphones, or tablets”; “I ask my child to maintain a distance of at least 35 cm when using computers, smartphones, or tablets”; and “I ask my child to make sure there is good lighting in their environment when they use computers, smartphones, or tablets.” Respondents also were asked the following question: “Do you limit the time your child spends on the Internet?” Each item was evaluated by using a 5-point Likert-type scale from “always” (scoring 5) to “never” (scoring 1). A higher score indicated a higher level of eye care parental mediation. The Cronbach's alpha for parental mediation was 0.88.

Parental mediation efficacy

Parental mediation efficacy of the eye care behavior of children was measured with four items. Sample statements included “I can ask my child to take a 10-minute break for every 30 minutes of computer, smartphone, or tablet use”; “I can ask my child to maintain a proper position and not lie on a bed or table when using computers, smartphones, or tablets”; and “I can limit the time my child spends on the Internet.” Each item was evaluated by using a 5-point Likert-type scale from “strongly confident” (scoring 5) to “strongly not confident” (scoring 1). A higher score indicated a higher level of parental mediation efficacy of eye care behavior. The Cronbach's alpha for parental mediation efficacy was 0.89.

Risk perception of mobile device use

Risk perception of mobile device use was measured by using nine items. Children and parents were asked as to whether they agreed or disagreed with statements such as “Posting personal information on smartphones or tablets has a risk of exposure”; “Frequently using smartphones or tablets decreases the time with family”; “Frequently using smartphones or tablets may be harmful to vision health”; and “Frequently using smartphones or tablets increases the risk of exposure to harmful content such as sexual and violent messages.” Each item was evaluated on a 4-point Likert-type scale ranging from “strongly agree” (scoring 4) to “strongly disagree” (scoring 1). A higher score indicated a higher level of risk perception of mobile device use. The Cronbach's alpha values for risk perception for the parent and child samples were 0.88 and 0.89, respectively.

Parental characteristics

The characteristics of the parents who participated in this study included gender (male or female), age, educational attainment, household income (lower-income class, lower-middle-income class, median-income class, and upper class), and marital status (married or divorced/separated).

Characteristics of the children

The characteristics of the children who participated in this study included gender (male or female), academic performance (good, average, or below average), household income (lower-income class, lower-middle-income class, median-income class, and upper class), and marital status of parent(s) (married or divorced/separated).

Statistical analysis

SAS software was used to perform the statistical analysis. Percentages and means were calculated for all variables. t Tests were conducted to examine the computer/mobile device screen time and the eye care behavior of children, as well as the computer/mobile device screen time of parents and parental mediation of eye care behavior with respect to socio-demographic characteristics. In addition, analysis was conducted to assess the correlation between a parent's practices, and the computer/mobile device screen time and eye care behavior of their children. Multiple regression analyses were also performed to identify factors related to parental mediation, computer/mobile device screen time of children, and the eye care behavior of children.

Findings

Computer/mobile device screen time and eye care behavior of children

Participant children included 1,367 boys (52.2 percent) and 1,254 girls (47.8 percent). Approximately 15 percent of the children reported that their parents were divorced or separated, whereas 25 percent of the children reported that their household income was of the lower or lower-middle class. One-fifth of children reported that their academic performance was below average. Overall, children spent about 16 hours a week using computers, smartphones, and tablets. Children spent more time on new media ([per week] smartphones, 7 hours; computers, 5 hours; and tablets, 4 hours) than on traditional media (television, 10 hours per week). Children reported an average daily screen time of 3.5 hours, which exceeds the American Academy of Pediatrics recommendations of 2 hours or less of daily screen time. Most (67 percent) children exceeded the American Academy of pediatrics guidelines, with boys accounting for 68.6 percent and girls slightly lower at 65.3 percent. Boys reported higher averages for weekly computer/mobile device screen time than girls, and children with lower academic performance, single parents, and a lower household income reported higher averages for computer/mobile device screen time (Table 1).

Table 1.

Computer/Mobile Devices Screen Time and Eye Care Behavior of Children by Socio-Demographic Variables

	Child's computer/mobile screen time (hours/week)			Child's eye care behavior
Child report	Mean	SD	t	Mean	SD	t
Total	14.96	16.00		3.73	0.77
Child's gender			−4.79^***			0.59
Girl	13.36	12.99		3.74	0.75
Boy	16.45	18.27		3.72	0.79
Academic performance			7.59^***			−10.22^***
Below average	20.09	18.00		3.41	0.80
Average	13.83	13.22		3.81	0.75
Parent marital status			5.84^***			−5.80^***
Divorced/separated	19.42	17.10		3.52	0.82
Married	14.15	3.53		3.77	0.74
Household income			2.29^*			−4.15^***
Low	16.34	19.39		3.62	0.77
Middle/high	14.60	14.80		3.77	0.77

Note: Children N = 2,621.

p < 0.05; ^***p < 0.001.

About one-fourth of children reported that they seldom or never took 10-minute breaks after every 30 minutes of using computers, smartphones, or tablets, and one-third of children reported that they often or always used smartphones or tablets before bedtime. Children with average/good academic performance implemented higher levels of eye care behavior, whereas children without household poverty also implemented higher levels of eye care behavior (Table 1).

Parental computer/mobile device screen time and mediation

Participating parents were made up of 1,687 mothers (69 percent) and 773 fathers (31 percent). Parents mainly were more than 45 years of age (80.8 percent), with college or higher education (58.1 percent) and middle/high household incomes (80.8 percent). Overall, parents spent about 25 hours a week using computers, smartphones, and tablets. Parents spent more time on new media ([per week] smartphones, 13 hours; computers, 8 hours; and tablets, 4 hours) than traditional media (TV, 11 hours per week). Compared with parents who were married, parents who were divorced or separated spent more time on computers and mobile devices (Table 2).

Table 2.

Computer/Mobile Screen Time of Parents and Parental Mediation of the Computer/Mobile Device Eye Care Behavior of Children by Socio-Demographic Variables

	Parent's computer/mobile screen time (hours/week)			Parental mediation of child's eye care behavior
Parent report	Mean	SD	t test	Mean	SD	t test
Total	24.40	24.28		4.04	0.74
Gender			−1.49			9.00^***
Female	24.85	22.85		4.13	0.68
Male	26.65	27.21		3.83	0.83
Age			1.09			3.69^***
Under 45 y/o	25.83	22.47		4.08	0.74
45 y/o and over	24.64	27.20		3.97	0.75
Education			−0.84			−6.39^***
High school and lower	24.88	26.07		3.93	0.81
College and higher	25.80	22.99		4.13	0.67
Marital status			2.36^*			−5.46^***
Divorced/separated	28.34	25.07		3.81	0.90
Married	24.84	24.04		4.08	0.70
Household income			−0.58			−5.78^***
Low	24.72	22.42		3.83	0.89
Middle/high	25.50	24.37		4.09	0.70

Note: Parent N = 2,460.

p < 0.05; ^***p < 0.001.

y/o, years old.

In general, parents reported high levels of parental mediation of the eye care behavior of their children (mean = 4.04, SD = 0.74). Mothers and younger parents more frequently imposed parental mediation of the eye care behavior of their children. In contrast, parents who reported lower educational levels, were separated or divorced, or reported a low household income were less inclined to impose parental mediation of the eye care behavior of their children (Table 2).

Correlation between parental practices and the eye care behavior of children

The computer/mobile device screen time of children was positively correlated with the computer/mobile device screen time of their parents (r = 0.120). The computer/mobile device screen time of children was negatively correlated, however, with their risk perception (r = −0.120), the level of parental mediation (r = −0.162), and the level of parental mediation efficacy (r = −0.200). In contrast, the eye care behavior of children was positively correlated with their risk perception (r = 0.193), and the level of mediation by their parents (r = 0.245), whereas the eye care behavior of children was negatively correlated with their computer/mobile device screen time (r = −0.421) (Table 3).

Table 3.

Correlation Coefficient Values Between Parental Practices, Child's Computer/Mobile Screen Time, and Eye Care Behavior

	1	2	3	4	5	6	7
1. Child's eye care behavior	1
2. Child's computer/mobile screen time	−0.421^***	1
3. Child's risk perception	0.193^***	−0.120^***	1
4. Parental mediation of eye care behavior	0.205^***	−0.162^***	0.063^**	1
5. Parental mediation efficacy	0.245^***	−0.200^***	0.072^***	0.510^***	1
6. Parent's computer/mobile screen time	−0.051^*	0.120^***	0.003	−0.066^**	−0.044^*	1
7. Parent's risk perception	0.098^***	−0.093^***	0.090^***	0.201^***	0.124^***	−0.030	1

p < 0.05; ^**p < 0.01; ^***p < 0.001.

Factors related to parental mediation of a child's eye care behavior

Multiple regression results showed that parents who were female, without household poverty, reported higher levels of mobile device risk perception, and reported a higher level of parental mediation efficacy were more likely to implement higher levels of parental mediation of the eye care behavior of their child (Table 4).

Table 4.

Factors Related to Parental Mediation of Child's Eye Care Behavior

	Parental mediation of child's eye care behavior
Parent report	β	SE	p
Intercept	1.89	0.11	<0.0001
Parent gender (female = 0, male = 1)	−0.22	0.03	<0.0001
Parent age (under 45 y/o = 0, 45 y/o, and over = 1)	−0.04	0.03	0.3253
Parent education (high school and lower = 0, college and higher = 1)	0.03	0.03	0.3253
Parent marital status (divorced/separated = 0, married = 1)	0.03	0.04	0.4140
Household income (low = 0, middle/high = 1)	0.10	0.04	0.0136
Parent risk perception	0.21	0.03	<0.0001
Parent computer and mobile devices use time	−0.001	0.001	0.0678
Parental mediation efficacy	0.40	0.02	<0.0001

Note: Multiple regression used. Parental mediation model N = 2,079.

Factors related to the computer/mobile device screen time of children and their eye care behavior

Multiple regression analysis revealed that boys who reported lower academic performance, were from a single-parent family, reported lower levels of mobile device risk perception, reported parents who spent more time using computers and mobile devices, and reported lower levels of parental mediation were more likely to spend more time using computers and mobile devices. In contrast, children who reported better academic performance, married parents, higher levels of risk perception, spent less time using computers and mobile devices, and had higher levels of parental mediation were more likely to have higher levels of eye care behavior (Table 5).

Table 5.

Factors Related to a Child's Computer/Mobile Device Screen Time and Their Eye Care Behavior

	Child's computer and mobile device use time			Child's eye care behavior
	β	SE	p	β	SE	p
Child report
Intercept	36.64	2.40	<0.0001	2.24	0.11	<0.0001
Child gender (female = 0, male = 1)	2.77	0.67	<0.0001	−0.01	0.03	0.7540
Child academic performance (below average = 0, average = 1)	−3.80	0.91	<0.0001	0.31	0.04	<0.0001
Parent marital status (divorced/separated = 0, married = 1)	−3.95	0.98	<0.0001	0.18	0.04	0.0001
Household income (low = 0, middle/high = 1)	−0.73	0.81	0.3685	0.02	0.04	0.5815
Child risk perception	−1.78	0.45	<0.0001	0.15	0.02	<0.0001
Parent report
Parent computer and mobile device use time	0.07	0.01	<0.0001	−0.01	0.01	0.0821
Parental mediation of eye care behavior	−3.16	0.46	<0.0001	0.17	0.02	<0.0001

Note: Multiple regression used. Child's computer/mobile screen time model N = 2,068. Child's eye care behavior model N = 2,077.

Discussion

The results of this study showed an average daily screen time of 3.5 hours for the children of Taiwan, whereas two-thirds of children exceeded the American Academy of Pediatrics recommendations of 2 hours or less for daily screen time. Boys who reported lower academic performance, were from a single-parent family, reported lower levels of mobile device risk perception, had parents who spent more time using computers and mobile devices, and had lower levels of parental mediation were more likely to spend more time using computers and mobile devices. Prior studies also found that family media-use rules could lower the amount of screen time for children.^4,22,23 At least one review study suggested that a reduction in the screen time of parents could lead to a decrease in the screen time of children. That study suggested improving parental practices, self-efficacy, and parenting style to decrease the amount of screen time for children.³⁴ Other studies have also suggested that intervention programs aiming at reducing the screen time of children should target both children and parents.^26,35,36 The United States Community Preventive Services Task Force also recommends family-based social support and behavioral interventions to reduce recreational sedentary screen time among children.³⁷

In this study, one-fourth of children reported that they seldom or never take a 10-minute break after every 30 minutes of computer, smartphone, or tablet use. In addition, children who reported better academic performance, married parents, higher risk perception, spent less time using computer and mobile devices, and had higher levels of parental mediation were more likely to have higher levels of eye care behavior. These results imply that school health programs should strengthen the levels of risk perception of children with respect to the use of computer/mobile devices, and these programs should also stress the importance of eye care behavior. Studies have indicated that increasing outdoor activities prevented children from myopia onset and development.^38,39 Schools and teachers could design more outside activities and teaching situations to encourage more outdoor play and learning opportunities for children.

The framework established by the World Health Organization Health Promoting Schools (HPS) program was effective in improving students' health outcomes.⁴⁰ During the past decade, the Taiwan government funded the HPS program to support school collaboration with communities, parent teacher associations (PTA), and experts in a concerted effort to promote the health of children. HPS programs collaborate with community eye physicians to conduct eye screening for children and to empower teachers and parents to provide supportive environments that will promote the vision health of children. For example, schools encouraged children to take part in outside activities during break times and to join sports clubs. In addition, schools asked children to take the eye-screening results and eye care information sheets home for parents to sign, whereas parents were requested to take their children to community eye clinics for further screening, treatment, and follow-up. Schools also collaborated with PTA to encourage parents to join children eye care activities, whereas teachers also implemented parent-child eye care co-learning activities to enhance parenting efficacy and to practice eye care behaviors such as increasing family participation in outside sports and limiting screen times. A study showed that the HPS program could improve the vision-health knowledge, attitudes, and behaviors of children,⁴¹ and that the vision health of children is crucial for academic achievement.⁴²

This study found that parents who were female, reported higher levels of risk perception and higher levels of parental mediation efficacy were more likely to implement higher levels of parental mediation of the eye care behavior of their children. These results were consistent with those of the EPPM²⁹ and a prior study that showed that parental mediation of smartphone use by children could be predicted by a perception of the severity of the problem, the response efficacy, and reports of self-efficacy.⁴³ Another study also showed that parents with a greater level of self-efficacy in restricting the screen time of their children and who perceived the importance of restricting child screen use tended to act on those convictions and to more often restrict the screen use of children.⁴⁴ Another study found that, compared with men, women tended to impose higher screen-time restrictions for their children, whereas adults with lower levels of screen use were more likely to restrict the screen time of their children.²⁵ These results implied that parental support programs should include parenting efficacy and modeling to empower parents with the skills that are necessary to help their children implement eye care behavior.

This study found that members of families with a low socioeconomic status (SES) spent more time on computers or mobile devices, and that parents with low SES tended to impose less parental mediation of the eye care behavior of their children. A prior study also found that children from low SES families were more likely to engage in longer screen times.⁴⁵ Child health inequalities might increase due to SES gaps in Internet literacy and parental mediation of Internet use.²⁸ The Taiwan government should continuously provide resources for schools and communities to implement effective programs that will enhance parental efficacy and reduce health inequalities, particularly for disadvantaged families.

Limitations

This study had some limitations. First, about one-seventh of children and one-fifth of parents refused to participate. However, the gender distribution in our sample of fifth-grade students was not significantly different from the total fifth-grade student population in Taipei city and New Taipei city. Second, social desirability bias may have had an influence on the truthfulness of reports of parental mediation, screen time, and eye care behavior. However, confidentiality was emphasized, and trained investigators collected the questionnaires immediately. Third, there were discrepancies between children and their parents regarding household income and parental marital status. The correspondence between the responses of parents and those of children with respect to parental marital status was 93 percent, but the correspondence between the two groups on household income was only 81 percent. To decrease the discrepancy, we categorized these variables to binary data and reported whether the data source was from a parent or a child. Finally, we excluded 31 and 44 Taipei City and New Taipei City parent questionnaires, respectively, because grandparents or other family relatives had completed them. Our results showed that, compared with parents, grandparents or other family relatives tended to report lower levels of mediation in child eye care behavior.

Conclusions

In conclusion, this study showed that the family unit is crucial in determining a child's screen time and eye care behavior. Children who were male, reported lower academic performance, were from a single-parent family, reported lower levels of mobile device risk perception, and reported parents who spent more time using computers and mobile devices, and reported lower levels of parental mediation were more likely to spend more time using computers and mobile devices. In contrast, children who reported better academic performance, were from an intact family, reported higher levels of risk perception, and reported higher levels of parental mediation were also more likely to report higher levels of eye care behavior.

Footnotes

Acknowledgments

This work was supported by a research grant from the Taiwan Ministry of Science and Technology. Many thanks go to the participant schools, students, and parents.

Author Disclosure Statement

No competing financial interests exist.

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