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Time for a view on screen time
Aric Sigman
INTRODUCTION
In Britain today, children by
the age of 10 years have
regular access to an average of
five different screens at home.
In addition to the main family
television, for example, many very young
children have their own bedroom TV
along with portable handheld computer
game consoles (eg, Nintendo, Playstation,
Xbox), smartphone with games, internet
and video, a family computer and a
laptop and/or a tablet computer (eg,
iPad). Children routinely engage in two
or more forms of screen viewing at the
same time, such as TV and laptop.
1
Viewing is starting earlier in life. Nearly
one in three American infants has a TV
in their bedroom, and almost half of all
infants watch TV or DVDs for nearly
2 h/day.
2
Across the industrialised world, watch-
ing screen media is the main pastime of
children. Over the course of childhood,
children spend more time watching TV
than they spend in school.
3
When includ-
ing computer games, internet and DVDs,
by the age of seven years, a child born
today will have spent one full year of
24 h days watching screen media. By the
age of 18 years, the average European
child will have spent 3 years of 24 h days
watching screen media; at this rate, by
the age of 80 years, they will have spent
17.6 years
4
glued to media screens.
Yet, irrespective of the content or edu-
cational value of what is being viewed,
the sheer amount of average daily screen
time (ST) during discretionary hours
after school is increasingly being consid-
ered an independent risk factor for
disease, and is recognised as such by
other governments and medical bodies
but not, however, in Britain or in most of
the EU. To date, views of the British and
European medical establishments on
increasingly high levels of child ST
remain conspicuous by their absence.
This paper will highlight the dramatic
increase in the time children today spend
watching screen media. It will provide a
brief overview of some specific health
and well-being concerns of current
viewing levels, explain why screen
viewing is distinct from other forms of
sedentary behaviour, and point to the
potential public health benefits of a
reduction in ST. It is proposed that
Britain and Europe’s medical establish-
ments now offer guidance on the average
number of hours per day children spend
viewing screen media, and the age at
which they start.
LEVEL OF CONSUMPTION: DOSE
Children of all ages today, are watching
more screen media than ever before.
5
Excluding any viewing time outside the
home, such as hand-held screen activities,
the average ST in the home for young
British adolescents is 6.1 h/day, and this
is rising significantly.
6
Canadian children
spend 7.8 h/day, and American children
7.5 h: 55% of their waking lives.
78
The
ongoing EU ToyBox study group has just
reported, ‘In general, parents had no
formal rules about TV viewing…
Remarkably, in most countries, parents of
a low SES had almost no rules regarding
watching TV. Children can watch TV all
day long or whenever they want.’
9
However, ST is no longer merely a cul-
tural issue about how children spend
their leisure time, nor is it confined to
concern over the appropriate/inappropri-
ate content of what is on the screen. It
has become a medical issue, often exhi-
biting a dose-response relationship with
disease risk.
SCREEN TIME GUIDELINES
The US Department of Health and
Human Services now cites reducing STas
one of its key ‘health improvement prior-
ities’in achieving its ‘national 10-year
health promotion and disease prevention
objective’:‘to increase the proportion of chil-
dren aged 0 to 2 years who view no television
or videos on an average weekday, and increase
the proportion of children and adolescents
aged 2 years through 12th grade [18 years]
who view television, videos, or play video
games for no more than 2 hours a day.’
10
The
Australian Department of Health and
Ageing has issued similar guidelines, as
has the American Academy of Pediatrics
(AAP), adding: ‘media—both foreground
and background—have potentially nega-
tive effects and no known positive effects
for children younger than 2 years.’
11 12
The Canadian Paediatric Society has gone
further, ‘No child should be allowed to
have a television, computer or video game
equipment in his or her bedroom.’
13
The
French Government prohibits French
channels from airing all TV programmes
—educational and otherwise—aimed at
children under 3 years of age.
14
What is the basis for this concern?
MORTALITY AND MORBIDITY
Numerous well designed prospective
cohort studies continue to find a highly
significant dose-response association
between ST and risk of type 2 diabetes,
cardiovascular disease (CVD) and all-
cause mortality among adults, with ST
identified as an independent risk factor
with biological plausibility.
15–17
Wijndaele et al
16
recently reported
that every 1 h/day increase in television
viewing was associated with a 6%
increased hazard for total fatal or non-
fatal CVD, and an 8% increased hazard
for coronary heart disease, independent
of gender, age, education, smoking,
alcohol, medication, diabetes status, CVD
family history, sleep duration and phys-
ical activity energy expenditure.
At the same time, others report that
for participants engaging in 4 h/day of
recreational ST (eg, TV, computers) rela-
tive to <2 h/day, there was a 48%
increased hazard for all-cause mortality,
and a 125% increased hazard for CVD
events of which 25% was explained by
cardiometabolic biomarkers.
18
In children and adults, ST has also
been found to have an unfavourable
dose-response association with a range of
biomarkers for CVD, type 2 diabetes and
metabolic syndrome (MetS) including
LDL/HDL/total cholesterol, triglyceride,
fibrinogen, systolic/diastolic blood pres-
sure (BP) and C-reactive protein.
16 19
Examining television/DVD/video and
computer use and metabolic risk, Hardy
et al
20
found that adolescent boys who
exceed 2 h/day of STwere more than twice
as likely to have abnormal levels of insulin
and homeostatic model assessment of
insulin resistance (HOMA-IR), suggesting
an increased risk of insulin resistance.
Another study involving 13–18.5-year-olds
in five Spanish cities found those watching
more than 3 h of TV per day had ‘signifi-
cantly less favourable levels’of HDL-
cholesterol, glucose, apolipoprotein A1 and
overall CVD risk scores.
21
VIEWING IS NOT MERELY
‘SEDENTARY BEHAVIOUR’
Nevertheless, the association between ST
and health risk appears not as simple as
ST merely being a sedentary behaviour.
First, sedentary behaviour as a risk factor
Correspondence to Dr A Sigman, Office 444, 91
Western Road, Brighton BN1 2NW, UK; aric@
aricsigman.com
Arch Dis Child Month 2012 Vol 0 No 0 1
Leading article
is distinct from too little moderate-to-
vigorous physical activity (MVPA) in all
age groups, with the two possibly being
separate constructs involving different
metabolic pathways contributing to
disease.
19 20 22 23
Prolonged ST elevates
health risk independent of the level of
MVPA people routinely engage in.
22
A
recent analysis of the ongoing US
National Institutes of Health Diet and
Health Study observed that even among
people with high levels of MVPA, high
amounts of television viewing remain
associated with a 47% increased risk for
all-cause, and a 100% increased risk for
cardiovascular mortality.
17
Another study
of body composition and abdominal
obesity in children across 10 European
cities has recently concluded that phys-
ical activity does not attenuate the
obesity risk associated with ST.
24
Moreover, children’s ST may be some-
what distinct from other forms of seden-
tary behaviour in its influence on
biological risk factors for disease.
23 25 26
For example, examining a range of seden-
tary behaviours, screen activities and BP
in young adolescents, Gopinath et al
25
reported a dose-response relationship,
‘each hour per day spent in screen time,
watching TV and playing video games
was associated with a significant increase
in diastolic BP of 0.44 ( p=0.0001), 0.99
(p<0.0001) and 0.64 mm Hg ( p=0.04),
respectively. By contrast, each hour per
day spent reading was associated with a
decrease…’ In prepubertal children, TV
viewing and total ST, but not computer
use, have been found to be positively
associated with both systolic and dia-
stolic BP, while painting or sitting were
not.
26
Additionally, different screen activ-
ities may have differing independent
associations with biomarkers and chronic
disease risk in youth.
23 26 27
A cross-sectional study of a large
sample of overweight and obese adoles-
cents concluded that time spent playing
seated video games was the only type of
ST associated with increased BP and total
cholesterol/HDL ratio.
27
Carson and
Janssen found in a representative popula-
tion of 6–19-year-olds that time spent
watching TV was predictive of a higher
score of an aggregated or clustered
measure of cardio-metabolic risk, but rec-
reational computer time was not.
23
While
in prepubertal children, Martinez-Gomez
et al
26
found that TV viewing but not
computer time was associated with
increased BP.
Studies of HPA stress-regulation and ST
shed further light on underlying mechan-
isms. Wallenius et al
28
found school-aged
children who had used Information and
Communication Technology (ICT) equip-
ment for an average of 3 h the preceding
day (only half the UK child norm)
showed a significantly reduced cortisol
increase 1 h after waking compared with
children who had not used ICT at all, or
for less than 1 h. ‘The results suggest a stress
response as a consequence of a long period of
ICTuse…[which] can persist over night and
have an impact on the regulation of
HPA-activity even the next morning.’They
suggest that child ST day after day may
‘predispose some adolescents to the devel-
opment of allostatic load.’There is
already concern that even HPA changes
within the normal range may be subtle
early indicators of, and contributors to,
unfavourable physical health outcomes in
adolescence and adulthood.
The educational value of screen mater-
ial being viewed does not preclude the
significant associations reported above
between ST and morbidity, mortality and
associated biomarkers.
OBESOGENIC MECHANISMS
Increased TV viewing has been consist-
ently shown to be linked to increased
body mass index (BMI) in both children
and adults independent of physical activ-
ity.
22 29
The association appears stronger
in young children. A cross-sectional study
assessing fat mass by Jackson et al
30
found a dose-response relationship: ‘Each
extra hour of watching TV was asso-
ciated with an extra 1 kg of body fat…
Preschool children who watch more TV
are fatter and are less active …the rela-
tion between TV viewing and fatness is
not mediated by physical activity…’.
ST is clearly associated with unhealthy
dietary behaviours in children, adoles-
cents and adults.
31
However, in addition
to the influence of food advertising,
studies of children’s ingestive behaviour
in direct response to screen viewing
suggest it can act as a distraction away
from vital satiation food cues toward
non-food cues (screen), thereby disrupt-
ing the development of habituation to
food and, therefore, increasing energy
intake while children are viewing.
32
Eating a meal while viewing screens is
also thought to disrupt the encoding and
memory formation of the meal. Impaired
memory for recent eating may increase
food intake hours after viewing stops. A
study in the journal Appetite found that
the ‘effects of television watching on
food intake extend beyond the time of
television watching to affect subsequent
consumption’.
33
In a randomised crossover study, video
game playing was found to significantly
increase food intake in adolescents imme-
diately after playing ‘and was not com-
pensated for during the rest of the day.’
34
One hour of playing a video game
resulted in a daily energy surplus of
163 kcal, a rate of 60 000 kcal/year, which
could help manufacture almost 8 kg of
body fat per year.
All these effects are taking place at a
time in our history when 68% of dinners
in the UK are eaten while watching
television.
5
Interestingly, a randomised controlled
clinical intervention trial divided 4–
7-year-olds into two groups: one had its
TV and computer viewing reduced by
half; the other did not. After 3 years,
there had been a significant reduction in
the BMI of those who had halved their
screen viewing, and relatively little in
those who had not.
35
The above findings may have signifi-
cant public health implications. Children
9–12 years with a high BMI are more
likely to have high BP, cholesterol and
blood insulin levels by adolescence.
36
Even marginally elevated BMI in adoles-
cence constitutes a substantial risk factor
for early occurrence of angiography-
proven coronary heart disease.
37
The EU
ToyBox study has in its ‘Evidence-based
recommendations for the development of
obesity prevention programs targeted
at preschool children’just called for
‘Limitation of leisure screen time to
<1 h/d (or the amount of time recom-
mended by appropriate national guide-
lines, if less than 1 h/d)’.
29
BRAIN AND COGNITION
ST is associated in a dose-response
manner with subsequent attention pro-
blems in a variety of age groups. A longi-
tudinal study of 2623 children reported
that children who watched television at
ages 1 and 3 years had a significantly
increased risk of developing attentional
problems by the time they were 7 years
old. For every hour of television a child
watched per day, there was a 9% increase
in subsequent attentional problems con-
sistent with a diagnosis of ADHD.
38
A longer-term dose-response association
has been found between television
viewing at the ages of 5 and 11 years,
and subsequent attention problems in
adolescence independent of early atten-
tion problems and other confounders.
39
Similar associations have been reported
in 14–22-year-olds, and in a study of
8–24-year-olds, Swing et al concluded,
‘Viewing television and playing video
2Arch Dis Child Month 2012 Vol 0 No 0
Leading article
games each are associated with increased
subsequent attention problems in child-
hood…late adolescence and early
adulthood…’.
40 41
In addition to ST, screen ‘speed’—the
pace of editing and degree of novelty
within screen material—is increasingly
thought to be an important factor in the
above findings. Lillard and Peterson
‘found that 9 minutes of viewing a
popular fast-paced fantastical television
show immediately impaired 4-year-olds’
EF [executive function], a result about
which parents of young children should
be aware.’
42
Dopamine is central to the ability to
pay attention and implicated in attention
problems. It is produced in response to
screen novelty. Significant dopamine
release within the striatum is found to
occur quickly in young adult brains while
playing computer games.
43 44
Dopamine
is also a key component of the brain’s
reward system, and is heavily implicated
in the formation and maintenance of
addictions. There are growing concerns
that extensive computer game playing
may lead to long-term changes in the
reward circuitry that resemble the effects
of substance dependence.
44
In addition to
computer games, screen viewing by
youngsters begets more viewing and,
unlike other sedentary behaviours, most
of the criteria of substance dependence
apply to people with higher levels of
ST.
45
Screen ‘addiction’, once a populist
catch phrase, is increasingly being used
by physicians to describe the growing
number of children engaging in screen
activities in a dependent manner.
46
PSYCHOSOCIAL HEALTH
ST is strongly associated with measures
of child mental well-being.
47–50
The AAP
has recently published a report on The
Impact of Social Media on Children,
Adolescents and Families, which contains
a section entitled ‘Facebook Depression’,
which is ‘defined as depression that devel-
ops when preteens and teens spend a
great deal of time on social media sites,
such as Facebook, and then begin to
exhibit classic symptoms of depression.’
51
A British study found that children who
spent more than 2 h/day watching televi-
sion or using a computer ‘were at [60%]
increased risk of high levels of psycho-
logical difficulties and this risk increased
if the children also failed to meet physical
activity guidelines. …Both television
viewing and computer use are important
independent targets for intervention for
optimal well-being for children, irrespect-
ive of levels of moderate/vigorous
physical activity (MVPA) or overall sed-
entary time.’
50
A cross-sectional analysis
of 9–10-year-old girls found ST to be
‘negatively associated with self-esteem’.
49
A survey of 3461 North American girls
aged 8–12 years found a significant asso-
ciation between STas well as measures of
media multitasking, and negative psycho-
social well-being.
Conversely, face-to-face communica-
tion was strongly associated with posi-
tive psychosocial well-being.
48
A study of
Japanese children aged 5–14 years reports
ST had a strong association with negative
feeling upon awakening and recommends
guidelines for child ST as a preventive
measure.
47
Adjusting for pre-existing individual
and family factors, a prospective longitu-
dinal study of 1314 Canadian children
found significant negative associations
between ST at 29 and 53 months of age,
and psychosocial well-being at age
10 years. Each 1 h increase in early child-
hood exposure corresponded to a 7% unit
decrease in classroom engagement and
10% unit increase in victimisation in
middle childhood. Researchers reported
‘Higher levels of early childhood televi-
sion exposure predicted greater chances of
peer rejection experiences such as being
teased, assaulted, or insulted by other
students …our results suggest that
reduced time for critical social interac-
tions in early childhood owing to dis-
placed time spent watching television
may present later specific risks of devel-
oping inadequate social skills.’
52
In understanding the above associa-
tions, several mechanisms have been pro-
posed. Humans require a certain amount
of ‘co-presence’—regular eye-to-eye
contact for optimal physical and mental
health.
53
Moreover, the fundamental
ability to relate to others is dependent on
social and emotional skills that are learnt
through regular social interaction.
Face-to-face conversations confer linguis-
tic skills, along with the ability to have
conversations—to know when and how
to listen and contribute. This learning
process is highly technical and time con-
suming.
54
For example, during
face-to-face interaction, in addition to
hearing a voice and accompanying facial
expressions of the speaker’s face, the
speech sounds produce tiny bursts of
aspiration—air pressure which hit the
child’s skin—tactile information contrib-
uting to auditory perception.
55
Neurobiology of socialisation
The development of empathy and com-
passion requiring subtle skills of reading
the nonverbal nuances of others’emo-
tions involve similar learning processes
which appear to have a neural basis. For
example, the insular cortex has been iden-
tified as a key brain mechanism involved
in experiencing the emotional states of
others and is thought to underlie egalitar-
ian behaviour in humans.
56
Feeling
empathy for a friend’s emotional suffer-
ing activates affective pain regions (dorsal
anterior cingulate cortex (dACC) and
insula) associated with having firsthand
experience of the same suffering.
57
The
learning effects of routinely experiencing
such social emotions are reflected neuro-
logically. The ‘deliberate cultivation of
compassion’through ‘compassion train-
ing’for empathic responses are associated
with changes in functional
neuroplasticity.
58
At the same time, researchers conduct-
ing functional magnetic resonance
imaging (fMRI) research have expressed
concern that when using the internet, for
example, the areas of the brain associated
with empathy showed virtually no
increase in stimulation, concluding
‘Young people are growing up immersed
in this technology and their brains are
more malleable, more plastic and chan-
ging than with older brains …As the
brain evolves and shifts its focus towards
new technological skills, it drifts away
from fundamental social skills.’
59 60
Mirror neurons
A child’s brain is also believed to have
multiple mirror neuron systems that spe-
cialise in carrying out and understanding
not just the actions of others, but their
intentions—the social meaning of their
behaviour and their emotions.
People who rank high on a scale meas-
uring empathy have particularly active
mirror neuron systems. A study of the
brain activity of 10-year-olds who
observed and imitated emotional expres-
sions and social skills found a direct rela-
tionship between the level of activity in
the children’s mirror neuron systems and
‘two distinct indicators of social func-
tioning in typically developing children’:
empathy and social skills. The authors
concluded that the importance of observ-
ing and copying everyday social beha-
viours and the mirror neuron system
‘may indeed be relevant to social func-
tioning in everyday life during typical
human development’.
61
It may be that children must exercise
specific brain areas and systems regularly
and extensively in situ, in order to
develop crucial social and emotional skills
or deficits will emerge later.
Arch Dis Child Month 2012 Vol 0 No 0 3
Leading article
A meta-analysis of 72 studies on
empathy conducted between 1979 and
2009 among almost 14 000 university
students ‘found the biggest drop in
empathy after the year 2000. College kids
today are about 40 per cent lower in
empathy than their counterparts of 20 or
thirty years ago, as measured by standard
tests of this personality trait.’The
authors believe that the sheer increase in
child and adolescent ST during this time
could be one very important factor, and
concluded that the rise of social media
may also play a role in the decline in
empathy: ‘The ease of having ‘friends’
online might make people more likely to
just tune out when they don’t feel like
responding to others’problems, a behav-
iour that could carry over offline.’They
also believe electronic media has contrib-
uted to a social environment that works
against slowing down and listening to
someone who requires sympathy.
62
Returning to the potential role of ST
in psychosocial learning, it is known that
younger children experience considerable
difficulty when translating to real life
what they see on a screen. Children learn
tasks better from a live demonstration
than from an equivalent televised demon-
stration, a problem referred to as the video
deficit.
63
This effect becomes more pro-
nounced and may persist at older ages as
the task complexity increases—and psy-
chosocial tasks, such as perceiving and
interpreting other’s actions, emotions
and intentions are highly complex.
Regarding the daily time available for
children to learn psychosocial skills
through face-to-face interactions, studies
at Stanford University have led to a ‘dis-
placement’theory of internet use:
In short, no matter how time online is
measured and no matter which type of
social activity is considered, time spent
on the Internet reduces time spent in
face-to-face relationships…an hour on
the Internet reduces face-to-face time
with family by close to twenty-
four minutes.
64
Sigman reported that between 1987
and 2007 the number of hours per day of
face-to-face social interaction declined
markedly as the use of electronic media
has increased.
65
INTERVENTIONS
There is good evidence that children’sST
can be reduced through simple measures,
mainly raising parental awareness. A sys-
tematic review by researchers at Harvard
Medical School recently reported that 29
studies ‘achieved significant reductions in
TV viewing or screen-media use’.
66
Research by the Centers for Disease
Control and Prevention (CDC), along
with other studies, has found parental
rules and limits on ST effectively reduce
ST, as does not having screens in bed-
rooms.
67 68
The CDC study also found a
negative dose-response relationship
between weekly physical activity and the
risk of exceeding recommended ST limits,
recommending the promotion of physical
activity as an additional means of redu-
cing ST.
Role modelling is another important
factor. Parent and child levels of screen
viewing are strongly related: children
who live in a household that promotes
TV-watching (TV is on when the child
comes home from school, and meals are
eaten in front of the TV) are more likely
to watch excessive amounts of television
themselves. If parents watch television
for more than 4 h/day, their son and
daughter, respectively, will be 10.5 and
three times more likely to watch it for
more than 4 h/day too.
69
RECOMMENDATIONS
The associations between ST and health
risks are reported to occur generally
beyond exposure of 2 h/day. Yet the
average child is exposed to three times
this amount. Therefore, reducing total
daily ST for children, and delaying the
age at which they start, could provide sig-
nificant advantages for their health and
well-being. Although popular phrases
such as ‘striking a balance’or ‘everything
in moderation’may sound reassuringly
sensible, one of the main obstacles in
encouraging parents to reduce their chil-
dren’s ST is the vagueness of the terms
‘moderation’and ‘excessive’.
Paediatricians must now define these
terms by first considering ST as simply
another form of consumption measured
in units of hours/minutes consumed per
day: a simple public health concept to
grasp and act upon. Considering the
existing empirical research and position
of medical bodies and governments in
other countries, the following guidance
on recreational ST (eg, before and after
school) are only ideals for parents. Even
if they are not adhered to, it is important
to establish such ideals as a reference
point to work from.
▸Eighty per cent of adult brain size
growth occurs during a child’sfirst
3 years, when they may be most vul-
nerable to the effects of screen media.
There should be a buffer zone in the
early years, whereby this stage of child
development is ‘cordoned off’from
premature exposure to screen media.
Screen viewing should be delayed, or
minimised, until age 3 years.
▸Encourage no screens in children’s
bedrooms.
▸Parents of younger children should be
advised to choose screen material with
a slower pace, less novelty and more
of a single narrative quality.
▸Parents should be encouraged to
monitor and control the time their
children spend on hand-held computer
games/media.
▸Ideal discretionary ST limits are:
–3–7 years: 0.5–1 h/day
–7–12 years: 1 h
–12–15 years: 1.5 h
–16+ years: 2 h
Parents must take into consideration
how much time their children are spend-
ing doing homework on computers
before coming to a decision on discretion-
ary ST for their child.
▸Parents should be aware of the role-
modelling influence their own viewing
habits may have on their children
along with the potential influence of
background or ‘passive’media.
▸Information about infants and tod-
dlers watching screens should be
included within maternity ward ‘birth
packs’given to mothers.
▸Health visitors should be aware of
medical evidence and advise new
parents.
▸Nurseries and day care centres should
make parents aware of this issue, as is
the case in Belgium and France.
▸Schools should adopt a position on
the amount of time children spend in
front of a screen in and out of school
and communicate this to pupils and
parents.
DISCUSSION
The study of STas a public health subject
is relatively new, and the associations
between ST and health risk cited in the
observational studies above do not prove
direct causation. While it is not possible
within the confines of this paper to
describe and compare the design and inde-
pendent variables, including the demo-
graphic profile of each study, others are
beginning to do so. For example, a
meta-analysis of relevant studies, includ-
ing some of the above, involving
European, US and Australian populations
on ST and risk of Type 2 Diabetes, CVD
and all-cause mortality carried out at the
Harvard School of Public Health, included
large sample sizes, long durations of
follow-up, and well established prospect-
ive studies. In addition, their pooled
4Arch Dis Child Month 2012 Vol 0 No 0
Leading article
estimates were based on prospective ana-
lyses with detailed adjustment for a wide
range of confounding variables. After
adjusting for BMI or other obesity mea-
sures and dietary variables, the associa-
tions with health risk still remained
highly significant.
15
The various studies finding associations
between ST and subsequent attention
problems were predominantly prospective
and controlled for relevant confounding
variables including pre-existing attention
problems.
38–41
Several of the above
studies on STand psychosocial well-being
used cross-sectional designs, making it
more difficult to determine whether
higher levels of ST were associated with
the development of negative well-being,
or negative well-being preceded higher
levels of ST.
47–50
For example, whether
children with psychological difficulties,
such as extreme shyness, are more likely
to gravitate towards ST over more soci-
able activities.
However, the prospective longitudinal
Canadian study controlling for pre-
existing psychosocial problems found sig-
nificant associations with ST.
52
There are additional concerns not
addressed above, regarding safeguarding
children from online exploitation and
exposure to inappropriate material. There
are also emerging concerns about the
potential effect of 3D screens on the
development of the child’s stereoscopic
vision and depth perception through pos-
sible alterations in the development of
the ‘fusion center’of the brain.
Interestingly, in their ‘Nintendo 3DS—
Parents’Information, 3D Concerns’,
Nintendo of America states, ‘children 6
and under should not use the 3D feature
of the Nintendo 3DS system.
70
The simple arithmetic of hours of
eye-to-screen contact versus eye-to-eye
contact are making clear the profound
implications of such extensive ST for
family and social relationships. In 2007,
when children had access to far fewer
screens, a large-scale study by Britain’s
Children’s Society found that television
alone was already displacing the parental
role, eclipsing ‘by a factor of five or ten
the time parents spend actively engaging
with children’.
An ongoing study of families in situ by
the University of California–Los Angeles
has found that social disengagement is
rapidly increasing, as side-by-side and
eye-to-eye human interactions in the
home are being displaced by the
eye-to-screen relationship. It was reported
that ‘family members seldom came
together as a group.’The number of
parents who were ignored or unacknow-
ledged on their return home because chil-
dren were ‘otherwise engaged in [screen]
activity…comprised a substantial percent-
age of observed behavior’. The high level
of being unacknowledged ‘encountered by
fathers when they reunited with their chil-
dren was particularly striking…These
latter results are particularly noteworthy.
Social scientists have long documented the
near universality of positive behavior in
the form of greetings when two or more
people reunite after being apart for a
period of time. Greetings recognize a
person’s arrival, status and display positive
intentions that universally facilitate the
transition into social interaction with
another.’ST has changed this.
71
Although this paper is concerned with
ST, when one includes screen content—
which may be very much at odds with
the values and desires of parents, but
which children may be absorbing for
many hours a day, the distorting effect
on the parental role in imparting their
own values and providing boundaries for
adolescence could be considerable. A
decade ago, in their ‘Analysis of
Children’s Programming Provision’, the
British Government’s Broadcasting
Standards Commission concluded ‘The
television is almost like a member of the
family in its own right’. With subsequent
birth of multiple screens, today extensive
ST appears to have created the three-
parent family.
Both within and outside the family,
children learn the rules of relationships
through extensive routine face-to-face
experience. Yet, as social media consumes
a larger portion of a child’s daily life, this
is likely to create difficulties in extrapolat-
ing on-line ‘un-boundaried’relationships
to those of the ‘real’world, thereby
affecting those relationships.
The family environment has been
described as an ecosystem of interruption
technologies. Background media that is
not being actively viewed by the child is
increasingly associated with developmen-
tal risks. A study of 5–6-year-olds found
that both active TV viewing and back-
ground ‘passive’TV exposure was related
to shorter sleep duration, sleeping disor-
ders and overall sleep disturbances.
Moreover, passive exposure to TV of more
than 3 h/day was strongly related to
sleep disturbances, therefore, ‘parents
should control the quantity of TV
viewing and …limit children’s exposure
to passive TV.’
72
A study of 1–3-year-olds
found that background TV significantly
reduced the amount of time they played
with their toys, and the amount of time
they spent in focused attention during
play. Researchers concluded, ‘These find-
ings have implications for subsequent
cognitive development.’
73
Researchers
have also found both the quantity and
the quality of interactions between
parents and children decline markedly
when background TV is on, which ‘may
have a negative impact on develop-
ment’.
74
Current US estimates for chil-
dren 8 months to 8 years of age are 3.9 h
of background TV per day.
75
The report
by AAP ‘recommends that parents and
caregivers …recognize that their own
[background] media use can have a nega-
tive effect on children’. The AAP consid-
ers claims by media industry executives
that educational media programmes are
meant to be watched by both the parent
and the child to facilitate social interac-
tions and the learning process as having
quite the opposite effect.
12
There are limitations in simply advis-
ing parents to reduce children’sST.As
with many preventative health initia-
tives, such advice may be least effective
in families where it matters most.
However, it is wrong to assume that it is
simply the underprivileged families being
referred to. The AAP recently reported
‘Parents who believe that educational
television is “very important for healthy
development”are twice as likely to keep
the television on all or most of the
time.’
12
Most parents want to reduce
health risks for their children, provided
they understand the rationale behind the
advisory, and a clear course of action is
offered. For example, between 1996 and
2007, children in England, exposed to
passive smoking, declined by nearly 70%.
Most interestingly, declines were greatest
in the 2 years immediately preceding legis-
lation as the result of, it is thought, the
media campaigns and greater publicity on
the impacts of passive smoking during
this period. Subsequent research has
found that ‘absolute declines in exposure
were greater in those most exposed at the
outset …including those living in lower
sociodemographic status households’.
76
At the moment, most parents and phy-
sicians are unaware of ST as a health
issue, and if they do harbour concerns,
they remain unaware of the rationale or a
clear rule of thumb as a course of action.
It is, therefore, an imperative to first
redress this knowledge void. Given that
many parents have grown to rely on ST
as a means of occupying their children—‘the
electronic babysitter’—any guidance on
ST would benefit from the inclusion of
suggestions for developing constructive
practical alternatives to ST.
Arch Dis Child Month 2012 Vol 0 No 0 5
Leading article
Although children may be regularly
involved in various screen activities and
using different screen devices, most ST is
recreational, that is, discretionary, and it
is this ST that should be the primary
public health target for reduction. There
may be scope for further reductions.
Preschool and infant schools, if made
aware of this issue, could easily reduce
ST, as much of it is predominantly discre-
tionary at that stage of education. Junior
and secondary schools could reconsider
the extent to which entertainment TV
programmes and films are used as lessons
and as ‘golden time’. There is a concern
that not to expose young children to
screen technology puts them at a devel-
opmental and educational disadvantage.
Furthermore, it is often assumed that if
children do not ‘get used to’screen tech-
nology early on, they will in some way
be intimidated by it, or be less competent
at using it later. However, research has
found that even Rhesus monkeys are
comfortable with, and capable of using,
the same screen technology that children
are exposed to.
77
The charity, Orangutan
Outreach, has been conducting trials
gauging iPad interaction with their apes.
The director has reported ‘It’s not really
toy-like because they are engaging with
them as devices …it’sdefinitely going in
the cognitive direction.’
78
Political implications
Perhaps because ST is not a dangerous
substance or a visibly risky activity, it has
eluded the scrutiny that other health
issues attract. Additionally, there is little
funding and public gratitude in looking
for the negative effects of the world’s
favourite pastime. In 2006, American
paediatric researchers writing in the
American Medical Association’sArchives
of Pediatric and Adolescent Medicine asked
rhetorically: ‘Why is it that something
that is widely recognised as being so
influential and potentially dangerous has
resulted in so little effective action?To b e
sure, there has been some lack of political
will to take on the enormously powerful
and influential entertainment industry …
[Screen] media need to be recognised as a
major public health issue’.
79
A problem of provenance
Rather than paediatricians, it has been
the academics in ICT, media literacy, edu-
cation, marketing and social and cogni-
tive psychology, whose research is often
funded by TV, software and technology
industries, who have dominated research,
public and professional understanding of,
and policy considerations on, ST and
child health. Few seem to have spotted
the most salient point: their focus is not
on child health, but as one leading insti-
tution advising successive British govern-
ments states, ‘research focuses on
children’s and young people’sinteractions
with [author’s italics] electronic media,
and on media education.’
Information hygiene
Moreover, while medical journals, such as
the BMJ group have instituted measures
to identify competing interests and
sources of funding, particularly regarding
the pharmaceutical industry, in order to
minimise such influence within their
publications, thereby maintaining a high
standard of information hygiene, the
culture and standard of hygiene with
respect to research on screen media and
children is very different in media, psych-
ology and education journals.
As the most valid impartial arbiter of
child health, British and European paedi-
atric medicine must in future be at the
centre of research, public understanding
and policy formation on ST.
In other areas of child health and
development, when considering the
potential effects of profound new devel-
opments, the paediatric health profes-
sion instinctively adopts a principle of
precaution. Yet, to date, the increasingly
excessive levels of child ST have been
met with relative silence. While many
questions remain regarding the precise
nature of the association between
ST and adverse outcomes, the advice
from a growing number of both research-
ers and other medical associations and
government health departments else-
where is becoming unequivocal: reduce
ST.
10–17 21 24 29 35 38 41 80–83
Irrespective
of whether this will endear paediatricians
to the public or not, Britain and Europe’s
medical establishments, including the
RCPCH, EAP and Department of Health,
should now formally express some
concern over ST.
A drop in viewing figures may be bad
for TV executives’blood pressure, but
may prove to be very good for child
health.
CONCLUSION
Children of all ages are spending more
time than ever before, watching screen
media. Viewing screen media is physiolo-
gically distinct from other forms of sed-
entary behaviour, with average daily ST
increasingly considered an independent
risk factor, often exhibiting a dose-
response relationship with disease and
unfavourable child development
outcomes. As health risks are reported to
occur beyond exposure of 2 h of ST per
day, although the average child is exposed
to three times this amount, a robust ini-
tiative to encourage a reduction in daily
recreational ST could lead to significant
improvements in child health and devel-
opment. Britain and European medical
establishments should consider ST as a
separate entity from sedentary behaviour,
and offer an advisory on the average
number of hours per day young children,
in particular, are viewing screen media,
and the age at which they start.
Contributors Author and guarantor: AS.
Funding None.
Competing interests The author declares: no support
from any organisation for the submitted work; no
financial relationships with any organisations that might
have an interest in the submitted work in the previous
3 years.
Provenance and peer review Not commissioned;
externally peer reviewed.
Accepted 11 July 2012
Arch Dis Child 2012;0:1–8
doi:10.1136/archdischild-2012-302196
REFERENCES
1. Jago R, Sebire SJ, Gorely T, et al.‘I’m on it 24/7 at
the moment’: a qualitative examination of
multi-screen viewing behaviours among UK 10–
11-year-olds. Int J Behav Nutr Phys Activ 2011;8:85.
2. Zero to Eight: Children’s Media Use in America.
Common Sense Media. 2011. http://www.
commonsensemedia.org/sites/default/files/research/
zerotoeightfinal2011.pdf
3. American Academy of Child and Adolescent
Psychiatry. Children & watching TV. Facts Fam
2001;54:1–2.
4. Sigman A. The impact of screen media on children:
a Eurovision for parliament. In: Clouder C, et al., eds.
Improving the quality of childhood in Europe 2012.
Vol 3. European Parliament Working Group on the
Quality of Childhood in the European Union,
2012:88–121.
5. TV Licencing. TeleScope: A focus on the nation’s
viewing habits from TV Licensing. UK, 2011. http://
www.tvlicensing.co.uk/resources/library/BBC/
MEDIA_CENTRE/TeleScope_report.pdf
6. OfCom. Children and parents: media use and
attitudes report. 2011. http://stakeholders.ofcom.org.
uk/binaries/research/media-literacy/oct2011/
Children_and_parents.pdf
7. Leatherdale ST, Ahmed R. Screen-based sedentary
behaviours among a nationally representative sample
of youth: are Canadian kids couch potatoes? Chron
Dis Injuries Canada 2011;31:141–6.
8. Centers for Disease Control and Prevention.
Obesity and Overweight for Professionals: Childhood:
A Growing Problem. 2011. p 3. http://www.cdc.gov/
obesity/childhood/problem.html
9. De Decker E, De Craemer M, De Bourdeaudhuij I,
et al., ToyBox-study group. Influencing factors of
screen time in preschool children: an exploration of
parents’perceptions through focus groups in six
European countries. Obes Rev 2012;13:75–84.
10. U.S. Department of Health and Human
Services. Healthy People 2020, Objective PA-8:
Increase the proportion of children and adolescents
who do not exceed recommended limits for screen
time. http://healthypeople.gov/2020/
6Arch Dis Child Month 2012 Vol 0 No 0
Leading article
topicsobjectives2020/objectiveslist.aspx?topicId=33
(accessed 10 Mar 2012).
11. Australian Department of Health and Ageing.
Education and Prevention: Non-productive sedentary
behaviour. Australian Government. http://www.health.
gov.au/internet/publications/publishing.nsf/Content/
gug-carer-toc~gug-carer-sedentary (accessed 24
Feb 2012).
12. American Academy of Pediatrics. Media use by
children younger than 2 years. Council on
communications and media. Pediatrics 2011;128.
doi: 10.1542/peds.2011-1753
13. Canadian Paediatric Society, Psychosocial
Paediatrics Committee.Impact of media use on
children and youth: Recommendations. http://www.
cps.ca/english/statements/CP/pp03-01.htm
(accessed 11 Mar 2012).
14. France bans marketing television programmes
targeted at under threes. The Telegraph.21
August 2008. http://www.telegraph.co.uk/news/
worldnews/europe/france/2595495/France-bans-
marketing-television-programmes-targeted-at-under-
threes.html (accessed 22 Feb 2012).
15. Grøntved A, Hu FB. Television viewing and risk of
type 2 diabetes, cardiovascular disease, and all-
cause mortality: a meta-analysis. JAMA
2011;305:2448–5.
16. Wijndaele K, Brage S, Besson H, et al. Television
viewing and incident cardiovascular disease:
prospective associations and mediation analysis in
the EPIC norfolk atudy. PLoS ONE 2011;6:e20058.
17. Mathews CE, George SM, Moore SC, et al.
Amount of time spent in sedentary behaviors and
cause-specific mortality in US adults. Am J Clin Nutr
2012;95:437–45.
18. Stamatakis E, Hamer M, Dunstan DW. Screen-
based entertainment time, all-cause mortality, and
car-diovascular events: population-based study with
on- going mortality and hospital events follow-up.
J Am Coll Cardiol 2011;57:292–9.
19. Pinto Pereira SM, Ki M, Power C. Sedentary
behaviour and biomarkers for cardiovascular disease
and diabetes in mid-life: the role of television-
viewing and sitting at work. PLoS ONE 2012;7:
e31132.
20. Hardy LL, Denney-Wilson E, Thrift AP, et al.
Screen time and metabolic risk factors among
adolescents. Arch Pediatr Adolesc Med
2010;164:643–9.
21. Martinez-Gomez D, Rey-López JP, Chillón P, et al.
Excessive TV viewing and cardiovascular disease risk
factors in adolescents. The AVENA cross-sectional
study. BMC Public Health 2010;10.
22. Inoue S, Sugiyama T, Takamiya T, et al. Television
viewing time is associated with overweight/obesity
among older adults, independent of meeting physical
activity and health guidelines. J Epidemiol
2012;22:50–6.
23. Carson V, Janssen I. Volume, patterns, and types of
sedentary behaviour and cardio-metabolic health in
children and adolescents: a cross-sectional study.
BMC Public Health 2011;11:274.
24. Rey-López J, Ruiz JR, Vicente-Rodríguez G, et al.
Physical activity does not attenuate the obesity risk
of TV viewing in youth. Pediatr Obes 2012;7:240–50
25. Gopinath B, Baur LA, Hardy LL, et al. Relationship
between a range of sedentary behaviors and blood
pressure during early adolescence. J Hum Hypertens
2011;26:350–6.
26. Martinez-Gomez D, Tucker J, Heelan KA, et al.
Associations between sedentary behavior and blood
pressure in young children. Arch Pediatr Adolesc Med
2009;163:724–30.
27. Goldfield GS, Baur LA, Hardy LL, et al. Video game
playing is independently associated with blood
pressure and lipids in overweight and obese
adolescents. PLoS ONE 2011;6:e26643.
28. Wallenius M, Hirvonen A, Lindholm H, et al.
Salivary cortisol in relation to the use of Information
and Communication Technology (ICT) in school-aged
children. Psychology 2010;1:88–95.
29. Summerbell CD, Moore HJ, Vögele C, et al.
Evidence-based recommendations for the
development of obesity prevention programs
targeted at preschool children. Obes Rev
2012;13:129–32.
30. Jackson DM, Djafarian K, Stewart J, et al.
Increased television viewing is associated with
elevated body fatness but not with lower total
energy expenditure in children. Am J Clin Nutr
2009;89:1031–6.
31. Pearson N, Biddle SJH. Sedentary behavior and
dietary intake in children, adolescents, and adults: a
systematic review. Am J Prev Med 2011;41:178–88.
32. Temple JL, Giacomelli AM, Kent KM, et al.
Television watching increases motivated responding
for food and energy intake in children. Am J Clin Nutr
2007;85:355–61.
33. Higgs S, Woodward M. Television watching during
lunch increases afternoon snack intake of young
women. Appetite 2009;52:39–4.
34. Chaput JP, Visby T, Nyby S, et al. Video game
playing increases food intake in adolescents: a
randomized crossover study. Am J Clin Nutr
2011;93:1196–203.
35. Epstein LH, Roemmich JN, Robinson JL, et al.A
randomized trial of the effects of reducing television
viewing and computer use on body mass index in
young children. Arch Pediatr Adolesc Med
2008;162:239–45.
36. Lawlor DA, Benfield L, Logue J, et al. Association
between general and central adiposity in childhood,
and change in these, with cardiovascular risk factors
in adolescence: prospective cohort study. BMJ
2010;341:c6224.
37. Tirosh A, Shai I, Afek A, et al. Adolescent BMI
trajectory and risk of diabetes versus coronary
disease. N Engl J Med 2011;364:1315–25.
38. Christakis DA, Zimmerman FJ, DiGiuseppe DL,
et al. Early television exposure and subsequent
attentional problems in children’.Pediatrics
2004;113:708–13.
39. Landhuis CE, Poulton R, Welch D, et al. Does
childhood television viewing lead to attention
problems in adolescence? Results from a prospective
longitudinal study. Pediatrics 2007;120:532–7.
40. Johnson JG, Cohen P, Kasen S, et al. Extensive
television viewing and the development of attention
and learning difficulties during adolescence. Arch
Pediatr Adolesc Med 2007;161:480–6.
41. Swing EL, Gentile DA, Anderson CA, et al.
Television and video game exposure and the
development of attention problems. Pediatrics
2010;126:213–21.
42. Lillard AS, Peterson J. The immediate impact of
different types of television on young children’s
executive function. Pediatrics 2011;128:644–9.
43. Koepp MJ, Gunn RN, Lawrence AD, et al. Evidence
for striatal dopamine release during a video game.
Nature 1998;393:266–8.
44. Weinstein AM. Computer and video game
addiction-a comparison between game users and
non-game users. Am J Drug Alcohol Abuse
2010;36:268–76.
45. Kubey R, Csikszentmihalyi M. ‘Television addiction is
no mere metaphor’.Sci Am Special Addition
2004;14:48–55.
46. Lin F, Zhou Y, Du Y, et al. Abnormal white matter
integrity in adolescents with internet addiction
disorder: a tract- based spatial statistics study. PLoS
ONE 2012;7:e30253.
47. Kondo Y, Tanabe T, Kobayashi-Miura M, et al.
Association between feeling upon awakening and
use of information technology devices in Japanese
children. J Epidemiol 2012;22:12–20.
48. Pea R, Nass C, Meheula L, et al. Media use,
face-to-face communication, media multitasking, and
social well-being among 8-to 12-year-old girls. Dev
Psychol 2012;48:327–36.
49. Racine EF, DeBate RD, Gabriel KP, et al. The
relationship between media use and psychological
and physical assets among third- to fifth-grade girls.
J Sch Health 2011;81:749–55.
50. Page AS, Cooper AR, Griew P, et al. Children’s
screen viewing is related to psychological difficulties
irrespective of physical activity. Pediatrics 2010;126:
e1011–17.
51. Schurgin O’Keeffe G, Clarke-Pearson K, Council On
Communications And Media. Clinical report—the
impact of social media on children, adolescents, and
families. Pediatrics 2011;127:799–804.
52. Pagani LS, Fitzpatrick CF, Barnett TA, et al.
Prospective associations between early childhood
television exposure and academic, psychosocial, and
physical well-being by middle childhood. Arch Pediatr
Adolesc Med 2010;164:425–31.
53. Holt-Lunstad J, Smith TB, Layton JB. Social
relationships and mortality risk: a meta-analytic
review. PLoS Med 2010;7:e1000316.
54. Abu-Akel A. The psychological and social dynamics
of topic performance in family dinnertime
conversation. J Pragmatics 2002;34:1787–806.
55. Gick B, Derrick D. Aero-tactile integration in speech
perception. Nature 2009;462:502–4.
56. Dawes CT, Loewen PJ, Schreiber D, et al. Neural
basis of egalitarian behavior. PNAS
2012;109:6479–83. doi: 10.1073/pnas.1118653109
57. Meyer ML, Masten CL, Ma Y, et al. Empathy for the
social suffering of friends and strangers recruits
distinct patterns of brain activation. Soc Cogn Affect
Neurosci Published Online First: 21 February 2012.
doi: 10.1093/scan/nss019
58. Klimecki OM, Leiberg S, Lamm C, et al. Functional
neural plasticity and associated changes in positive
affect after compassion training. Cereb Cortex
Published Online First: June 1 2012. doi: 10.1093/
cercor/bhs142
59. Immordino-Yang MH, McColla A, Damasioa H,
et al. Neural correlates of admiration and
compassion. Proc Nat Acad Sci 2009;106:8021–6.
60. Small G. Research shows that Internet is Rewiring
our Brains. UCLA Faculty and Staff News. 15
October 2008. http://www.today.ucla.edu/portal/ut/
081015_gary-small-ibrain.aspx
61. Pfeifer JH, Iacobonia M, Mazziottaa JC, et al.
Mirroring others’emotions relates to empathy and
interpersonal competence in children. NeuroImage
2008;39:2076–85.
62. Konrath S, O’Brien EH, Hsing C. Changes in
dispositional empathy in American college students
over time: a meta- analysis. Pers Soc Psychol Rev
2011;15:180–98.
63. Elizabeth Zack E, Barr R, Gerhardstein P, et al.
Infant imitation from television using novel
touch screen technology. Br J Dev Psychol
2009;27:13–26.
64. Nie NH, Stepanikova I, Pals H, et al.Ten years after
the birth of the internet: how do Americans use the
Internet in their daily lives? Report: Stanford Institute
for The Quantitative Study Of Society. Stanford
University; 2005.
65. Sigman A. Well connected? The biological
implications of social networking. The Biologist
2009;56:14–20.
66. Schmidt ME, Haines J, O’Brien A, et al. Systematic
review of effective strategies for reducing screen time
among young children. Obesity 2012;20:1338–54.
67. Carlson SA, Fulton JE, Lee SM, et al.Influence of
limit-setting and participation in physical activity on
youth screen time. Pediatrics 2010;126:e89–96.
68. Ramirez ER, Norman GJ, Rosenberg DE, et al.
Adolescent screen time and rules to limit screen time
in the home. J Adolesc Health 2011;48:379–85.
Arch Dis Child Month 2012 Vol 0 No 0 7
Leading article
69. Jago R, Fox KR, Page AS. Parent and child physical
activity and sedentary time: do active parents
foster active children? BMC Public Health
2010;10:194.
70. Nintendo of America. Nintendo 3DS—Parent s’
Information, 3D Concerns. 2012. http://www.nintendo.
com/consumer/systems/3ds/en_na/parents.jsp
71. Campos B, Graesch AP, Repetti R, et al. Opportunity
for interaction? A naturalistic observation study of
dual-earner families after work and school. JFam
Psychol 2009;23:798–807.
72. Paavonen EJ, Pennonen M, Roine M, et al.TV
exposure associated with sleep disturbances in
5-to 6-year-old children. J Sleep Res
2006;15:154–61.
73. Schmidt ME, Pempek TA, Kirkorian HL, et al. The
effects of background television on the toy play
behavior of very young children. Child Dev
2008;79:1137–51.
74. Kirkori an HL, Pempek TA, Murphy LA, et al.
The impact of background television on
parent–child interaction. Child Dev
2009;80:1350–9.
75. Lapierre M, Piotrowski M, Linebarger D. Background
television in the homes of American children. Paper
presented at the International Communication
Association’s Annual Conference; 24–28 May 2012,
Phoenix, AZ, USA.
76. Bauld L. The impact of smokefree legislation in
England: evidence review. University of Bath, 2011.
Central Office of Information. http://www.dh.gov.uk/
en/Publicationsandstatistics/Publications/
PublicationsPolicyAndGuidance/DH_124961
(accessed 2 Aug 2012).
77. The Tulane National Primate Research Center
How Smart are Monkeys? Tulane University. 2006.
http://www.tnprc.tulane.edu/public_faq.html#20
(accessed 8 Jul 2012).
78. Ape versus machine: Do primates enjoy computer
games? BBC Nature, 8 February 2012. http://www.
bbc.co.uk/nature/16832378 (accessed 8 Jul 2012).
79. Christakis DA, Zimmerman FJ. Media as a public
health sssue. Arch Pediatr Adolesc Med
2006;160:445–6.
80. Mark AE, Janssen I. Relationship between screen
time and metabolic syndrome in adolescents.
J Public Health 2008;30:153–60.
81. Dunstan DW, Barr ELM, Healy GN, et al. Television
view- ing time and mortality. The Australian Diabetes,
Obesity and Lifestyle Study (AusDiab). Circulation
2010;121:384–91.
82. Paavonen EJ, Roine M, Korhonen P, et al.Mediaand
children’swell-being.Duodecim 2011;127:1563–70.
83. Wijndaele K, Brage S, Besson H, et al. Television
viewing time independently predicts all-cause and
cardiovascular mortality: the EPIC Norfolk study. Int J
Epidemiol 2011;40:150–9.
8Arch Dis Child Month 2012 Vol 0 No 0
Leading article