What the Research Tells Us About The Impact of TV

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National Center for Infants, Toddlers and Families
What the Research Tells Us About
The Impact of TV/Video Viewing on Children Under Three
The need to understand the impact of TV viewing on children under age three is critical
at a time when TV is in 99% of homes in the US, and when a 2003 Kaiser Family
Foundation study revealed that millions of parents are allowing their children under two
to watch 2 or more hours of TV a day. This publication is a summary of the most robust
research on what is currently known and not known about the influence of television
viewing on very young children’s development.
Although this is not a comprehensive literature review of every published study regarding
media’s impact on young children, this publication describes the small body of research
studies which included children aged birth to three in their samples. The findings of these
studies, as well as their strengths and limitations, are presented. This summary concludes
with suggested media use guidelines for parents of babies and toddlers based on the
research.
This research summary is the result of a collaboration between ZERO TO THREE and
several researchers who have done considerable work exploring the impact of the media
on very young children—Rachel Barr, Ph.D., Assistant Professor at Georgetown
University, Dan Anderson, Ph.D., Professor of Psychology at University of
Massachusetts at Amherst, and Deborah L. Linebarger, Ph.D., Assistant Professor at the
University of Pennsylvania. This document has also been reviewed by several researchers
in the field of early childhood development, including ZERO TO THREE Board
members Ross Thompson, Ph.D., Professor of child Psychology at the University of
California and Hiro Yoshikawa, Ph.D., Associate Professor of Applied Psychology and
Public Policy at New York University. Rebecca Parlakian and Claire Lerner, ZERO TO
THREE staff members, were the lead writers and editors of this report.
ZERO TO THREE has collaborated with Sesame Workshop on the Sesame Beginnings
DVD series to provide parents with young children with a tool to encourage parent-child
interaction. In addition, both Drs. Barr and Anderson are paid consultants to Sesame
Workshop.
Babies begin attending to television programming early in life.
Research finds that infants begin to be regularly exposed to television at a relatively early
age—starting at 9 months.i Media use only increases from that point onward:
• 74 percent of children under age two have watched televisionii
• 59 percent of children under age two watch television for an average of
two hours per dayiii
• 30 percent of children aged zero to three years old have a television in
their bedroomiv
Notable is that very young children attend to television in different ways, based on their
ages:v
• Babies younger than 6 months attend to loud voices and sudden noises on
television.
• Babies 6-10 months old are attracted to specific sounds (e.g., drumming, a
character’s voice, laughter) on television.
• Babies aged 10-18 months old focus on music, content (simple stories),
and television characters.
Content that is not developmentally appropriate, or that is not understood by children,
does not seem to attract their attention.
•
One early study (Anderson & Levin, 1976) compared one- to four-year-old
children’s attention to Sesame Street and found that attention paid to the program
by four-year-olds was dramatically higher as compared to one-year-olds.vi
•
A similar study had two-, three-and-a-half, and five-year-old children exposed to
both comprehensible and incomprehensible (reordered scenes, foreign language,
or backwards speech) video clips of Sesame Street. Children’s attention to the
incomprehensible segments was significantly less than to the normal ones,
indicating that when television content is not understandable to children, they pay
less attention to it.vii
•
Most recently, a study of 12- to 18-month-olds viewing infant-directed
programming has shown that attention is high and sustained, averaging 60-80%.viii
Program content matters.
A growing body of research shows that any television outcome is heavily influenced by
the specific content viewed.
•
In one study by Linebarger and Walker, a series of statistical models were
calculated to analyze the growth of toddlers’ vocabulary rates as a function of
exposure to different television content. The analyses were designed to estimate
the association between specific televised content and vocabulary for children
watching a particular program by comparison with children who did not watch
that program. The researchers found that vocabulary rates grew most when
children were exposed to Dora the Explorer, Blue’s Clues, Dragontales, Arthur,
and Clifford between 6 and 30 months of age.ix Vocabulary rates grew least
when children were exposed to Sesame Street and the Teletubbies. Viewing
Barney and Friends was associated with reduced vocabulary but increased
expressive language.
•
The negative association with expressive language found for children viewing
Sesame Street may be accounted for by two important factors. First, Sesame
Street is not designed for children under 2, but for preschoolers. In addition, the
Sesame program that the children viewed was developed before Sesame Street’s
format was redesigned to make the story vignettes contiguous, rather than more
discrete or broken up. For children viewing the Teletubbies, researchers theorized
that aspects of this program, such as its loose narrative structure, intense auditory
and visual stimulation, and poor language models (characters mainly use
“babytalk”), may have inhibited expressive word use.x
•
Researchers believe that engagement strategies in programs like Blue’s Clues and
Dora the Explorer, in which characters speak directly to the child and actively
elicit their participation, encourage expressive language production and
vocabulary. In programs such as Arthur, Clifford, and Dragon Tales, their strong
narratives and story-book like structure may have supported language
development.
•
In a follow-up analysis of the data, the researcher found that repeated exposure to
Sesame Street videos was related to higher vocabulary growth (Linebarger,
2005).xi Repetition of the content and higher music content in the program may
be contributing factors.
Limitations
This study included a small, homogenous sample size (51 White middle to upper
middle class families), which may limit the ability to generalize these findings,
especially to a more socio-demographically diverse population.
Comment
While the sample size is small and homogenous, the results indicate that television
content affects children’s outcomes in different ways and perhaps at different times
across development.xii Some programs may have a positive impact on language
development while others may have a negative impact. This suggests that future
studies should examine the effects of specific content, not TV viewing time alone.
Currently, studies on young children and the media often do not distinguish among
programs according to their content.
Co-viewing may enrich children’s viewing experience.
There have been variable findings on the frequency of parent-child co-viewing.
•
In one study with older children, 3- and 5-year-olds and their families participated
in a two-year study of their television viewing patterns. Five, 1-week diaries for
all family members were collected at 6-month intervals. This study found that,
when parents co-view with their preschool children, it largely occurs around
adult-oriented programs (i.e., not developmentally appropriate for young
children), rather than child-oriented or educational programs.xiii
•
Another study found that, among 300 surveyed parents of children aged birth to
23 months, television and videotapes were reported to be co-viewed 47% of the
time.xiv
•
The Kaiser Foundation Zero to Six Study in 2003 found that 69% of parents
indicated that, for most of the time that their child aged birth to 6 was watching
television, he or she was watching with someone else.xv
•
The tendency to co-view is supported by research conducted by Schmitt (2001)
who found that, when 2- and 3-year-olds watch television in their homes, their top
two most frequent activities while viewing include (1) interacting with another
child or caregiver; and (2) playing with toys.xvi
•
In research by Lemish and Rice, when parents and their infants or toddlers
(sample ranged in age from 6 months to 2 years, 5 months) co-viewed television
in their homes, there tended to be multiple occurrences of language-related
behaviors that emerged from this shared experience.xvii For example, some
children labeled objects on the screen, asked questions about the program,
repeated television dialogue, and/or described the program content. Parents’
verbalizations included answering children’s questions, answering questions
posed by television characters on the screen, and repeating words from the
program.
•
A study of 120 12- 15- and 18-month-olds viewing infant-directed programming
showed that attention is dependent upon the frequency of parent questions, labels
and descriptions during the video, suggesting the important role that parent-child
interaction may play during television viewing.xviii
Limitations
•
The Lemish and Rice study’s limitations include a small sample size of 16 children
who ranged in age from 6 months to 2 years, 5 months.
•
Generalization from the data on the impact of co-viewing on children under age one
is discouraged. Given the rapid developmental changes in young children, it is
critical for there to be more age-specific studies on co-viewing with children under
age 2.
Comment
The study results suggest that television can facilitate children’s language development
from 6 months to 3 years of age, if parents are active participants who interpret the
television programs their children watch. In the Lemish and Rice study on co-viewing
mentioned above, it was observed that parents tended to use the television as a teaching
tool similar to the way they read books to their infants.
Children under 2 can learn from TV, but not as effectively as from real
life.
There have been several studies that reveal a “video-deficit”. The video deficit is the
phenomenon that children younger than age three have difficulty transferring what they
view on screen to real life and consistently learn less from television than from a live
demonstration.
•
Research has found that 14- and 24-month-olds can imitate specific manipulations
of toys performed by adults on video immediately after viewing the video and 24
hours later.xix Another, similar study found that when televised demonstrations
are repeated, even 6-month-olds can imitate simple actions from television.xx
•
A study by Lemish found that after children (ranging in age from younger than 6
months to 18 months old) repeatedly viewed programs that featured regularly
appearing characters, they became familiar with and attentive to those characters.
They were also able to recognize those characters in other contexts, such as in
books or stuffed animals.xxi
•
Research by Mumme and Fernald (2003) found that babies as young as 12 months
old were capable of responding to emotional cues shown on televisionxxii. Babies
aged 10- and 12-months old were given unfamiliar objects (e.g., plastic valve) to
explore, touch, etc. Next, babies watched a videotape in which an actor
responded in either a positive or negative manner to each of these objects. The
researchers then showed the babies the objects a second time. The 10-month-olds
were apparently uninfluenced by the video. The behavior of the 12-month-olds,
however, suggested they had been influenced by the video, but only by the
negative emotion. Note that the actual objects were in front of the baby during
the viewing activity, which may have helped the baby understand what the adult
was referring to. Having relevant props available for babies to look at may help
them interpret the information they are seeing on the screen.
•
Barr and Hayne found that the ability for children aged 12, 15 or 18 months to
imitate multi-step sequences, such as shaking a rattle, from televised images
lagged behind their ability to learn from live, observed events. Learning through
an interaction with another person was a more effective means of gaining new
information.xxiii
•
A follow-up study (Barr and colleagues, under revision) has shown that when the
actual demonstration on television was longer and babies saw the actions more
frequently, they were able to imitate the same amount from television as from a
real interaction.xxiv In addition, infants as young as 6 months were able to copy
actions from television.xxv This suggests that learning from television is a
complex process that may require more time (i.e., repetition) for the information
to be processed.
•
A study by Troseth and DeLoache asked 2 and 2 ½ -year-olds to watch a monitor
showing an experimenter hide a toy in a room. The children were then asked to
find the toy in the actual room shown on the monitor. When the hiding event was
presented on television, younger children completed the task with significantly
more errors than when they watched the hiding event through a window,
illustrating their difficulty in using information from a televised event to
understand a real-life situation.xxvi This suggests that children under 2 ½ are
developing symbolic thinking—the ability to understand that one thing can
represent another—a skill that young children generally master between ages 2
and 3. In this study, it is possible that the younger children don’t yet grasp that
the picture of the room on television is a symbolic representation of a real room.
As a result, they have difficulty transferring information viewed on the screen to
the actual setting it represents. Older children, who have grasped the concept of
symbols, can apply more readily what they see represented on the screen to real
life.
•
Additional research by Troseth (2003) showed that there are ways to help younger
(pre-symbolic thinking) children learn from the televised event.xxvii In this study,
every day for two weeks, parents were asked to hook up video cameras to the
family television and film their children as the children simultaneously watched
the TV screen. Researchers found that 2-year-olds who have experienced seeing
themselves on television perform better on the hiding task described above.
•
In their most recent study, Troseth, Saylor and Archer (2006) found that
interactivity helps children learn and apply information from TV.xxviii One group
of 2-year-olds watched a person—whom they did not know—on a closed-circuit
TV for 5 minutes. This televised person engaged in a variety of activities with the
children, such as playing Simon Says and telling children where to find a sticker
in the room. The televised person responded in a contingent way to the children's
actions, commenting on what children were doing while playing Simon Says or
when a child found the sticker. The person on TV also called the children by
name. The second group of children watched a five-minute video tape that was
made of the person on the closed-circuit TV during her interaction with the first
group of children. The televised person was not, of course, responding
contingently to the children in the second group. For example, she often
commented on their actions, such as the retrieval of the sticker, before the
children had actually found it.
After this 5 minute period, the two groups of toddlers participated in the hiding
game described above. They were told by a person on TV where to find a toy in
the adjacent room. The researchers found that 2-year-olds in the socially
contingent group could retrieve the hidden object but 2-year olds in the second,
non-contingent group failed to find the object. They concluded that 2-year-olds
expect socially contingent reactions from other people; when they detect the lack
of contingency in televised presentations, learning from television is disrupted.
Once again, this suggests that watching television with a parent who makes the
viewing experience interactive may play a role in helping toddlers understand this
medium.
Comment
In the studies above where live and televised learning were nearly the same, embedding
the learning or task within a familiar context for the baby may have had an influence on
the results. Learning occurs best when it is embedded in everyday, familiar, or routine
contexts. Utilizing more naturalistic or realistic contexts may reduce the cognitive “load”
associated with learning.
Amount of TV exposure matters.
Some studies found that as viewing time increased, so did the potential for negative
effects.
• One study showed a correlation between parental reports of television viewing at
1 and 3 years of age and subsequent parental reports of attentional problems at
age 7.xxix
• Another study established a correlation between early television viewing at 1 year
of age and irregular sleep schedules at 4 years of age.xxx
One study looking at TV and attention found no impact.
•
A recent study by Munslow and Stevens (2006) found that children’s attentional
processes were not impacted by early television exposure.xxxi
Limitations
In conducting the first 2 studies, parents were asked to report how much television their
young child watched on a typical day. However, researchers did not ask participants
what the children were watching. Of note, is that when these data were collected, there
were hardly any programs or videos designed for children under age 3, so while
programming content may have influenced the findings, content was not assessed. As a
result, the correlations that researchers established in these studies can tell us little about
the impact of viewing content developmentally appropriate for children aged birth to
three.
Background television matters.
Background television is programming that is simply on “in the background” and that is
not the primary focus of the child’s attention. The impact of background television raises
questions since it is frequently programming that is not created for children and is most
likely incomprehensible to very young children.
•
One recent study found that 39 percent of children between the ages of 0 and 4
live in households where the television is always on or is on most of the time,
even if no one is watching.xxxii
•
Research has found that having the TV on in the background interrupts the
duration of play bouts in 1-year-oldsxxxiii.
Comment
The concern about background television is that in addition to interfering in children’s
play, it may reduce interaction between parent and child, creating obstacles to learning on
two fronts. Also of note is that many studies of the impact of television on young
children, it is difficult to determine if researchers are measuring background television or
televised content that is actively watched by young children.
There is a negative correlation between television viewing and
interacting with parents and siblings.
Several studies have cited negative associations between television viewing and time
spent with parents engaging in other activities.
•
One recent study (Vandewater, Bickham, & Lee, 2006) established a correlation
between TV viewing and parent-child interactionsxxxiv. Participants included a
nationally representative sample of children aged 0 to 12 in 1997 (N = 1712).
Twenty-four-hour time-use diaries from 1 randomly chosen weekday and 1
randomly chosen weekend day were used to assess children's time spent watching
television, time spent with parents, time spent with siblings, time spent reading
(or being read to), time spent doing homework, time spent in creative play, and
time spent in active play.
Results indicated that time spent watching television both with and without
parents or siblings was negatively related to time spent with parents or siblings,
respectively, in other activities. Television viewing also was negatively related to
time spent doing homework for 7- to 12-year-olds and negatively related to
creative play, especially among very young children (younger than 5 years).
There was no relationship between time spent watching television and time spent
reading (or being read to) or to time spent in active play.
Limitations
This study’s primary limitation is that it is correlational in nature. It is not clear that
television viewing is the cause of children spending less time interacting with parents or
engaged in other activities. There are many other variables that may influence both
television viewing patterns and the amount of time parents and children spend engaged in
shared interactions or activities. For example, it has been suggested that the relation
between TV viewing and parent-child interactions may be an indicator of a broader
pattern of family relationships, such that even without television, parents and children
may not necessarily be spending more time together.xxxv Further research is needed,
therefore, to clarify the association between television viewing and family interaction
patterns.
There is an association between amount of television viewing and
obesity.
•
One recent study focusing on very young children found that the likelihood of
obesity among low-income multi-ethnic preschoolers (aged one to five years) was
higher for each hour per day of TV or video viewed.xxxvi
•
A study by Lumeng et al. found that 3-year-old children exposed to two or more
hours of television per day were nearly three times as likely to be overweight than
children who either watched or were in a room with a TV on for fewer than two
hours a day, regardless of the child’s environment at home.xxxvii
•
Work by Vandewater and Huang (2006) examined the relationship between
television viewing and children's weight status, taking into account parental
weight status.xxxviii In this study, a population-level survey with a representative
sample of 1483 children aged 6 to 19 years of age, the results indicate that when
parental obesity is taken into account, television viewing hours do not
significantly relate to increased odds of children being overweight. It may be that
parental body mass index serves to moderate the relationship between television
viewing and child weight status among adolescents, and that televised viewing
may not cause but be a complex correlate of family weight problems. Further
research is needed to examine these associations with a sample of families with
younger children.
There is no research concerning television viewing and young children’s
brain development.
There is currently no research on the impact of TV viewing on early brain development
that we could identify.
Conclusion
It is clear that further research is needed before definitive conclusions can be reached
concerning the developmental outcomes of television or video watching for young
children. While several of the studies reviewed above are experimental designs, the
majority are correlational. Correlational studies—in which naturally-occurring television
viewing patterns in families are statistically associated with developmental changes in
children’s conceptual and/or language development— cannot be used to infer causation.
That is: Correlation does not equal causation. Television-viewing and children’s early
conceptual growth may appear to be associated because they are each influenced by
common variables, including but not limited to, parenting style, values and practices,
number of siblings in the home, and socio-economic status.
For correlational studies to be useful in the context of young children and the media, it
would be important that they: (a) control systemically for potentially extraneous variables
(such as those listed above), and (b) systematically evaluate the kinds of variables that are
likely to moderate the impact of viewing on young children. Such variables include:
frequency of co-viewing with a sibling or adult, specific age of child, other activities
occurring while viewing, the content of the programming, its developmental
appropriateness, and other variables. Currently, there is no research of this kind. As a
result, any inferences concerning the impact of television viewing on early childhood
development must be tentative and qualified by existing studies’ limitations.
These limitations include:
• Small sample sizes;
• Lack of diversity within the sample; and/or
• The only variable examined was amount of television watched, with no regard
given to what children watched (programming content).
Additional research is needed to isolate and better understand what components (e.g.,
programming content, length of viewing, age and developmental stage of child) are most
significant in shaping a child’s experience with television programming. Specifically,
studies featuring large-scale, specific age cohorts, diverse populations and studies which
examine the implications of both length of time viewed and programming content would
be valuable additions to the literature. Of particular importance is the need for more
research on the impact of media on children under one year given the lack of studies with
this age group. In addition, great caution should be taken about generalizing any of the
findings reported in this document to children under one.
In the absence of conclusive findings, parents can use the current research to inform the
creation of “house rules” on television viewing that also reflect their own values and
beliefs. Some guidance is offered below.
i
Linebarger, D. L., & Walker, D. (2005 January). Infants’ and toddlers’ television viewing and language
outcomes. American Behavioral Scientist, 48(5), 624-645.
ii
Kaiser Family Foundation. (2003, October). Zero to six: Electronic media in the lives of infants,
toddlers and preschoolers. Menlo Park, CA: Author.
iii
Ibid.
iv
Ibid.
v
Lemish, D. (1987). Viewers in diapers: The early development of television viewing. In T. R. Lindlof
(Ed.), Natural audiences: Qualitative research of media uses and effects (pp. 33-57). Norwood, NJ:
Ablex.
vi
Anderson, D. R., & Levin, S. R. (1976). Young children’s attention to Sesame Street. Child
Development, 47, 806-811.
vii
Anderson, D.R., Lorch, E.P., Smith, R., Bradford, R., & Levin, S.R. (1981). Effects of peer presence on
preschool children's television-viewing behavior. DevelopmentalPsychology, 17, 446-453.
viii
Barr, R., Zack, E., Muentener, P., & Garcia, A. (in progress). Parent-infant interactions during exposure
to infant-directed programming in 6- to18-month-olds.
ix
Linebarger, D. L., & Walker, D. (2005 January). Infants’ and toddlers’ television viewing and language
outcomes. American Behavioral Scientist, 48(5), 624-645.
x
Ibid.
xi
Linebarger (2005, April). Infants’ and toddlers’ video and on-air viewing and language development.
Paper presented at the biennial meeting of the Society for Research on Child Development, Atlanta, GA.
xii
Linebarger, D. L., & Walker, D. (2005 January). Infants’ and toddlers’ television viewing and language
outcomes. American Behavioral Scientist, 48(5), 624-645..
xiii
St. Peters, M., Fitch, M., Huston, A. C. Wright, J. & Eakins D. (1991). Television and Families: What
Do Young Children Watch with Their Parents? Child Development, 62, 1409-1423.
xiv
Weber, D. S., & Singer, D. G. (2004 September). The media habits of infants and toddlers: Findings
from a parent survey. Zero to Three, 25(1), 30-36.
xv
Rideout, V. J., Vandewater, E. A., & Wartella, E. A. (2003 Fall). Zero to six: Electronic media in the
lives of infants, toddlers, and preschoolers. Menlo Park, CA: The Henry J. Kaiser Family Foundation.
xvi
Schmitt, K. M. (2001, October/November). Infants, toddlers, & television: The ecology of the home.
Zero to Three, 22(2), 17-23.
xvii
Lemish, D. (1987). Viewers in diapers: The early development of television viewing. In T. R. Lindlof
(Ed.), Natural audiences: Qualitative research of media uses and effects (pp. 33-57). Norwood, NJ:
Ablex.
xviii
Barr, R., Zack, E., Muentener, P., & Garcia, A. (in progress). Parent-infant interactions during
exposure to infant-directed programming in 6- to18-month-olds.
xix
Meltzoff, A. N. (1988). Imitation of televised models by infants. Child Development, 59, 1221-1229.
xx
Barr, R., Muentener, P., Garcia, A. (under revision). Age-related changes in deferred imitation from
television by 6- to 18-month-olds. Developmental Science.
xxi
Lemish, D. (1987). Viewers in diapers: The early development of television viewing. In T. R. Lindlof
(Ed.), Natural audiences: Qualitative research of media uses and effects (pp. 33-57). Norwood, NJ:
Ablex.
xxii
Mumme, D. L., & Fernald, A. (2003). The infant as onlooker: Learning from emotional reactions
observed in a television scenario. Child Development, 74(1), 221-237.
xxiii
Kaiser Family Foundation. (2003, October). Zero to six: Electronic media in the lives of infants,
toddlers and preschoolers. Menlo Park, CA: Author.
xxiv
Barr, R., Muentener, P., Garcia, A., Chavez, V. & Fujimoto (under revision). The effect of repetition
on imitation from television during infancy. Developmental Psychobiology.
xxv
Barr, R., Muentener, P., & Garcia, A. (under revision). Age-related changes in deferred imitation from
television by 6- to 18-month-olds. Developmental Science.
xxvi
Troseth, G. L., & DeLoache, J. (1998). The medium can obscure the message: Young children’s
understanding of video. Child Development, 69, 950-965.
xxvii
Troseth, G. L. (2003). TV guide: Two-year-old children learn to use video as a source of information.
Developmental Psychology, 39(1), 140-150.
xxviii
Troseth, G. L., Saylor, M. M., & Archer, A. H. (2006). Young children's use of video as a source of
socially relevant information. Child Development, 77, 786-799.
xxix
Christakis, D. A.., Zimmerman, F. J., DiGiuseppe, D. L., & McCarty, C. A. (2004 April). Early
television exposure and subsequent attentional problems in children. Pediatrics, 113(4), 708-713.
xxx
Thompson, D. A., & Christakis, D. A. (2005). The association between television viewing and
irregular sleep schedules among children less than 3 years of age. Pediatrics, 116(4), 851-856.
xxxi
Munslow, T. & Stevens, M. (2006). There is no meaningful relationship between exposure to television
and symptoms of Attention-Deficit Hyperactivity Disorder. Pediatrics, 117, 665-672.
xxxii
Vandewater, E. A., Bickham, D. S., Lee, J. H., Cummings, H. M., Wartella, E. A., & Rideout, V. J.
(2005 January). When the television is always on: Heavy television exposure and young children’s
development. American Behavioral Scientist, 48(5), 562-577.
xxxiii
Anderson, D. R. & Pempek, T. A. (2005). Television and very young children. American Behavioral
Scientist, 48, 505-522.
xxxiv
Vandewater, E. A., Bickham, D. S., & Lee, J. H. (2006). Time well spent? Relating television use to
children's free-time activities. Pediatrics,117, 181-91.
xxxv
Ibid.
xxxvi
Dennison, B. A., Erb, T. A., & Jenkins, P. L. (2002). Television viewing and television in bedroom
associated with overweight risk among low-income preschool children. Pediatrics, 109(6), 1028-1035.
xxxvii
Lumeng, J. C., Rahnama, S., Appugliese, D., Kaciroti, N., & Bradley, R. H. (2006). Television
exposure and overweight risk in preschoolers. Archives of Pediatrics & Adolescent Medicine, 160(4), 417422.
xxxviii
Vandewater, E. A., & Huang, X. (2006). Parental weight status as a moderator of the relationship
between television viewing and childhood overweight. Archives of Pediatric Adolescent Medicine,160,
425-31.
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