Parent awareness of young children's physical activity
, Noe C. Crespo
, Esther M.F. van Sluijs
, Nanette V. Lopez
, John P. Elder
UKCRC Centre for Diet and Activity Research (CEDAR), Institute of Public Health, University of Cambridge, United Kingdom
Arizona State University, School of Nutrition and Health Promotion, Exercise and Wellness Program, USA
Institute for Behavioral and Community Health, San Diego State University, USA
MRC Epidemiology Unit, Cambridge, United Kingdom
Available online 2 July 2012
Objective. Parents who overestimate their child's physical activity (PA) level may not encourage their chil-
dren to increase their PA. We assessed parental awareness of child PA, and investigated potential correlates of
Method. ChildPA (accelerometer) and parent-classiﬁed child PA [‘active’ ≥ 60 min/day vs. ‘inactive’ b 60 min/
day moderate and vigorous PA (MVPA)] were measured over 7 days [n=329, 44% male, 39% Latino; mean (SD)
9.1 (0.7)years] in an obesity prevention study in San Diego (Project MOVE). Agreement between date-matched
objective MVPA and parent-classiﬁed child PA was assessed; % days parental overestimation was the outcome
variable. Associations between parental overestimation and potential correlates were investigated using
three-level mixed‐effects linear regression.
Results. Children met the PA guidelines on 43% of days. Parents overestimated their children's PA on 75% of
days when children were inactive. Most parents (80%) overestimated their child's PA on ≥1measurement
day. Parental support for child PA (transport, encouragement and participation with child) (pb 0.01) was posi-
tively associated with higher overestimation. Parents of girls showed more overestimation than parents of
Conclusion. Most parents incorrectly classiﬁed their child as active when their child was inactive. Strategies
addressing parental overestimation may be important in PA promotion.
© 2012 Elsevier Inc.
Insufﬁcient physical activity (PA) is a risk factor for obesity in chil-
dren (Steele et al., 2008; Wareham et al., 2005). Only 42% of US children
aged 6–11 years meet PA guidelines which are ≥60 min of moderate
and vigorous PA (MVPA) every day (Troiano et al., 2008). Literature re-
views highlight the limited success of PA interventions in children
(Dobbins et al., 2009; Salmon et al., 2007; van Sluijs et al., 2007b); how-
ever the reasons for this are largely unknown.
One possible explanation for the limited effectiveness of PA interven-
tions is that individuals overestimate their PA level, believing themselves
to be more active than they really are. This misperception is common for
PA (Corder et al., 2010, 2011b; Lechner et al., 2006; Ronda et al., 2001;
van Sluijs et al., 2007a, 2007b; Watkinson et al., 2010), due to unclear
thresholds between healthy and unhealthy PA levels (Ronda et al.,
2001). Someone overestimating their PA level may not be aware that
they are not optimally active and may see no need to increase their PA
level (Ronda et al., 2001). Improving PA awareness by reducing over-
estimation of PA levels may be an important component of PA promo-
tion. Few interventions address this as a key strategy (Ronda et al.,
2001; van Sluijs et al., 2007a, 2007b) although it has been considered
in recent interventions in adults (van Stralen et al., 2010).
Parents strongly inﬂuence the PA of their children, and usually have
primary responsibility for their participation in PA promotion (Giles-
Corti et al., 2009). Investigation of parental awareness of child PA levels
is important as parents may need to be aware that their children are in-
sufﬁcie ntly active in order to facilitate their participation in PA promo-
tion (Corder et al., 2010).
To our knowledge, parental awareness of child PA has not been in-
vestigated among US or ethnically diverse children and parents. Previ-
ous studies have used one habitual PA awareness question to deﬁne
overestimation (Corder et al., 2010, 2011b; Lechner et al., 2006;
Ronda et al., 2001; van Sluijs et al., 2007a, 2007b; Watkinson et al.,
2010). This is the ﬁrst study to derive parental overestimation using
daily awareness data, allowing for daily variation in children's PA.
We investigated parental awareness of child PA levels among parents
of 7–10‐year-old children, and explored correlates of parental over-
Preventive Medicine 55 (2012) 201–205
Abbreviations: PA, physical activity; MVPA, moderate and vigorous physical activity.
⁎ Corresponding author at: Centre for Diet and Activity Research (CEDAR), Box 296,
Institute of Public Health, University of Cambridge, Forvie Site, Robinson Way, Cambridge,
CB2 0SR, United Kingdom. Fax: +44 1223 330316.
E-mail address: email@example.com (K. Corder).
0091-7435 © 2012 Elsevier Inc.
Contents lists available at SciVerse ScienceDirect
journal homepage: www.elsevier.com/locate/ypmed
Open access under CC BY-NC-ND license.
Open access under CC BY-NC-ND license.
Study design and setting
Children (5–8 years old) and their primary caregivers (n=541 dyads) liv-
ing in San Diego County were recruited between November 2006 and May
2008 to participate in Project MOVE, a 2-year obesity prevention study involving
recreation centers. Families were contacted through phone calls, ﬂiers and com-
munity information booths. Parent–child dyads lived within 1.75 miles from 1
of 30 participating recreation centers and parents could speak and read English
or Spanish. Parents provided written informed consent and children provided
oral assent. Ethical approval from San Diego State University Institutional Re-
view Board was obtained. Post-intervention data were used here (children
7–10 years old) as accelerometer data were available for the majority of partic-
At baseline and post-interventionmeasurement sessions,parents completed
a questionnaire,and child and parent anthropometricmeasures were taken. Par-
ents reported demographics for themselves and their child including: age,
gender, Latino ethnicity, family monthly income (b $500–$2000, $2001–$3500,
$3501–$5000 and≥ $5001)and parent education (middle school or lessthrough
post-graduate). Height (Shorr Measuring Height Board) and weight (SECA 880
and876) were assessed using standardproceduresby trained staffto the nearest
0.1 cm and 0.1 kg, respectively. Body mass index (BMI) z‐scores were calculated
(Center for Disease Control and Prevention, 2000).
At post-intervent ion, PA was assessed using Actigraph accelerometers
(Ekelund et al., 2001, 2003). All children agreeing to wear a monitor (n=370)
were ﬁtted with a GT3X or GT1M (recording in 5-s epochs), and asked to wear
the monitors for 7 days while awake and to remove them for water-based activ-
ities. Accelerometry d ata were analyzed using a program available at http://
Programme%205_Disclaimer.html to remove: data recorded between 11 pm
and 6 am, periods of ≥ 30 min with continuous zero counts and days with
b 540 min of recording (valid day cut-off).
Time (min/day) spent in MVPA was derived using age‐speciﬁccut-points
(Trost et al., 2005). Accelerometer data were used to derive a dichotomous
MVPA variable; 60 min/day of MVPA was used to classify children as active or in-
active, according to current PA guidelines (US Department of Health and Human
Services, 2008). “Classiﬁcation error” was calculated as daily child MVPA (min)
minus 60 min (current guidelines). Seven categories of time in MVPA were cal-
culated in 15‐min blocks (from zero to ≥ 90 min) to examine the distribution
of PA levels with regard to parental overestimation.
Parental awareness of child PA
Parental awareness of child PA level was assessed through a daily diary, con-
current with accelerometer measurement, asking the parent: “was your child
physically active for a total of at least 60 minutes on this day” with answer cate-
gories as “yes” and “no”.
For each day with valid PA and awareness data, parent–
child dyads were categorized into one of four groups using objective and
parent-classiﬁed PA (Fig. 1). The outcome variable for this analysis was “parental
overestimation”, expressed as the percentage of measured days on which par-
ents overestimated their child's PA level (number of days of parental PA over-
estimation divided by the number of days with valid matched data). Only one
child per parent was enrolled in the study and parents were asked to respond
to all surveys for that child only. A sensitivity analysis was done using 45 min
as the threshold between active and inactive.
Potential correlates of overestimation were parentally reported at follow-up
(except baseline values for sex, ethnicity, income and parental education).
Cronbach's alpha was compute d to determine the internal consistency of items
Two questions asked parents how many days/week their child plays team
and non-team sports with eight responses options (0–7 days/week): a sum of
both questions was used to represent sessions/week that the child does sport.
Parents reported the presence of eight PA-related rules, including “do not go
places alone” (ICC=0.42–0.74) (Kerr et al., 2008). Responses were “yes”, “no”
and “sometimes” with “no” and “sometimes” combined given that if a rule is
only ‘sometimes’ present it is unlikely to be enforced.
Parents reported how often they provide encouragement and transport for
their child to do PA, and how often they do PA with their child. Response op-
tions were “never”, “b once/week”, “1–2 times/week”, “3–4 times/week” and
“5–7 times/week” recoded as 0, 1.5, 3.5 and 6 days/week. Parent support for
less sedentary time was derived from two questions “to help children think of
ways to be less inactive” an
d “encouraging less inactive time” with responses
as above (α=0.79).
Parents reported electronic media items in the child's bedroom using an
adapted published scale (Rosenberg et al., 2010) (previously reported ICC=
0.90). Parents reported the number of types of PA equipment at home (range
0–8) using an adapted scale (original reliability ICC=0.80) (Rosenberg et al.,
Parents selected the frequency of their child's PA participation at 11 loca-
tions (including recreation centers and parks), response categories were
never, b once/week, 1–2times/week,3–4 times/week and 5–7 times/week
(recoded as 0, 1.5, 3.5 and 6 days/week). These have been reported previously
Accelerometer assessed PA level
≥ 60 min/d MVPA
< 60 min/d MVPA
• Yes Realistic Active
37.9 % ( n= 622 )
Mean (SD) MVPA:
42.6 % ( n= 700 )
Mean (SD) MVPA:
Parent classified child PA
level: “Was your child
physically active for a total
of at least 60 minutes on
this day? ”
• No Underestimation
5.3 % ( n= 87 )
Mean (SD ) MVPA:
14.2 % ( n= 233 )
Mean (SD) MVPA:
Fig. 1. Derivation of parental overestimation (n=1642 measurement days) by comparison of parent rated child PA levels and accelerometer assessed PA levels among 329 children
and parents from San Diego County, CA. MVPA, moderate and vigorous PA; min/d, minutes per day.
202 K. Corder et al. / Preventive Medicine 55 (2012) 201–205
(original reliability ICC=0.60–0.89) (Kerr et al., 2008). Two composite vari-
ables were derived: locations used frequently (sum of locations used ≥ 1–2
times/week) and total weekly visits to any location (times/week) (Corder et
Characteristics of those included and excluded from the analyses
were tested using t-tests or chi-squared tests.
Simple associations between parental overestimation and potential
correlates were assessed using three-level mixed‐effects linear regres-
sion with levels as days, children and recreation center recruitment
area. Analyses were additionally adjusted for sex, study condition and
classiﬁcation error. Classiﬁcation error was included as a covariate so re-
sults are independent of child MVPA and proximity to the guideline
threshold. This also takes into account that overestimation depends on
PA levels. Study condition was adjusted for but intervention effects
were not assessed. Variables that reached p≤ 0.10inthesimplemodels
were included in a multiple model and subsequently removed if
p≥ 0.05, variables were removed stepwise, starting with the highest
p-value. Stata 12.0 (Statacorp, College Station, TX) was used for analyses.
Of the 541 Project MOVE parent–child dyads, 329 had at least one
matched day of objective and parent-classiﬁed PA data (mean (SD)
5.0 (1.9)days); descriptive data are presented in Table 1.Therewere
no signiﬁcant differences by sex, parent education, ethnicity, age or
BMI z‐score between Project MOVE children excluded and included
from these analyses (all p>0.05).
Fig. 1 shows the grouping of measurement days into four PA aware-
ness categories by objective and parent-classiﬁed PA level. In total, 1642
valid measurement days were included. Results primarily focus on over-
estimation as those children did not meet PA guidelines on some mea-
surement days and their parents may therefore not encourage them to
participate in PA promotion.
Parents wrongly classiﬁed their child's PA level on 48% of measured
days and overestimated their child's PA on 43% of all measured days. Chil-
dren were not meeting PA guidelines (determined using accelerometry)
on 57% of valid measurement days and parents overestimated their
children's PA level on 75% of these inactive days. Parents overestimated
their child's PA level on mean (SD) 2.1 (1.8)days/week, with 80% over-
estimating on ≥ 1 measurement day. Parents who overestimated their
child's PA level did so by a mean (SD) of 22.0 (13.3)min/day.
Table 1 shows a summary of the simple associations between individ-
ual factors and parental overestimation. Table 2 shows the distribution of
parental classiﬁcation error by categorical objective PA level. Classiﬁca -
tion error is similar across the four PA categories of b 60 min/day.
Table 3 shows descriptive data on home and family factors and sim-
ple associations with parental overestimation. Parent encouragement,
transport provision for PA and parents doing PA with their child were
positively associated with parental overestimation. The only variable
remaining in the ﬁnal model was parents providing transport for PA
(β (95% CI) 2.3 (0.9, 3.7) pb 0.01).
Sensitivity analyses using 45 min of MVPA as the guideline thresh-
old showed parents overestimating their child's PA on 27% versus 43%
of all days. Sex was no longer signi
ntly associated with % days over-
estimation (B (95% CI) p value as 4.3 (− 0.3, 0.8) p=0.07) but all other
associations were similar.
Most parents incorrectly classiﬁed their child as meeting PA guide-
lines on days when children were actually inactive (not meeting the
PA guideline). Most parents overestimated their child's PA level at
some point during the measurement period. As this is the ﬁrst study ad-
dressing parental awareness in an ethnically diverse population and
using a daily measure, these ﬁndings emphasize the relevance of paren-
tal overestimation in PA promotion.
The parents in the present study had similar levels of overestimation
as a previous British study (Corder et al., 2010). The high prevalence of
overesti mation identiﬁed in both studies supports the potential impor-
tance of further research regarding parental awareness. As shown previ-
ously, parental overestimation was higher for parents of girls (Corder et
al., 2010) and may be partly due to the lower PA level of girls versus boys.
The lack of association with BMI contrasts previous results suggesting
that parents who overestimate their child's PA level have children with
lower fat mass (Corder et al., 2010).
Parent overestimation of child PA was higher among parents who
reported more parent support for child PA. Apart from sex, these paren-
tal support variables were the only factors associated with parental
overestimation and providing transport was the only variable to remain
in the ﬁnal model. The parental burden of providing support including
transport to PA locations may lead parents to assume that their child
is sufﬁciently active even if the child is not meeting guidelines. Although
parental PA support is positivelyassociated with child PA (vander Horst
et al., 2007), providing more support appears to be associated with
Descriptive data for 329 parent–child dyads from San Diego County, CA with data on
parental estimation of child PA and results of simple three-level linear regression for
associations with parental overestimation (% days parental overestimation).
Variable Mean (SD) or % B (95% CI) P value
Sex (% boys) 44.1 Reference category
Sex (% girls) 55.9 6.0 (0.3, 11.8) 0.04
Age (years) 9.1 (0.7) 3.8 (−0.1, 7.7) 0.06
BMI z‐score 0.6 (−2.6, 2.8) 1.7 (− 1.2, 4.7) 0.25
Ethnicity (% non-Latino)
61.4 Reference category
Ethnicity (% Latino)
38.6 − 2.7 (−8.5, 3.2) 0.38
Monthly income (% parents)
$0–$2000 22.1 Reference category
$2001–$3500 20.1 − 1.7 (−10.8, 7.4) 0.72
$3501–$5000 22.5 − 3.8 (−12.6, 5.0) 0.39
$5001+ 35.3 − 0.2 (−8.1, 7.8) 0.97
Middle school or less 15.5 Reference category
High school 13.7 − 0.1 (−10.6, 10.6) 0.99
Some college but
26.1 − 0.3 (−9.4, 8.8) 0.95
College graduate 26.8 − 3.4 (−12.4, 5.7) 0.47
Post-graduate work 17.9 − 4.2 (−14.1, 5.7) 0.41
MVPA (min/day) 59.4 (25.8)
− 0.6 (25.8) − 0.4 (− 0.4, − 0.3) b 0.01
B; beta estimated regression coefﬁcient from three-level mixed‐effects linear regres-
sion and adjusted for study condition, classiﬁcation error (MVPA min) and sex with
outcome variable as % days of parental overestimation; 95% CI, 95% conﬁdence interval;
MVPA, moderate and vigorous physical activity; PA, physical activity.
Association with % days of parental overestimation.
Descriptive data for 329 parent–child dyads from San Diego County, CA on percentage
days of parental overestimation (n=1642 days) and classiﬁcation error by category of
moderate and vigorous activity.
Mean (SD), %
Mean (SD) classi ﬁcation error
0–14.9 73 44.3 (42.6) − 44.8 (5.4)
15–29.9 227 50.7 (38.6) − 29.5 (9.2)
30–44.9 308 51.7 (34.4) − 16.1 (11.4)
45–59.9 325 45.6 (32.2) − 5.3 (10.5)
60–74.9 239 0 6.1 (9.6)
75–89.9 181 0 14.6 (10.9)
≥ 90 289 0 38.7 (22.9)
PA, physical activity; MVPA, moderate and vigorous activity.
Classiﬁcation error calculated as difference from 60-min guideline.
203K. Corder et al. / Preventive Medicine 55 (2012) 201–205
higher overestimation. Even if parents support their children to engage
in PA, this may still not be sufﬁcient to meet guidelines. A potential strat-
egy might be to encourage parents to consider whether their child's activ-
ities are sufﬁciently ‘active’ to meet guidelines. This ﬁnding also supports
promotion of active travel perhaps as an alternative to parents providing
motorized transport for children to do PA. Findings may be due to reverse
causality as parents who have identiﬁed their child as insufﬁcien tly active
may have started providing support. Higher overestimation was positive-
ly associated with parental support which questions our initial hypothe-
sis that parents who wrongly consider their child as active will not
encourage their child to do PA. However, it is possible that inactive chil-
dren still need additional parental support in order to meet guidelines.
A trial is necessary to establish whether parental overestimation can be
reduced, whether this increases parental encouragement and whether
this also increases child PA.
Parental monitoring of child PA in addition to parental education
about adequate PA levels for children may target parental overestimation
of child PA, but this needs investigation in a trial. Other complementary
intervention strategies including goal setting and personalized feedback
to parents about their children may improve parental awareness and in-
crease children's PA (Michie et al., 2009). Self-monitoring step counts
using pedometers has potential in PA promotion among children but
more research is necessary to establish how self-monitoring can be used
most effectively (Lubans et al., 2009) and how best to involve parents.
We are unable to determine causation from this cross-sectional
analysis. Results are from post-intervention measurements from an
obesity prevention intervention. Analyses were adjusted for study con-
dition and the intervention did not speciﬁcally target PA awareness but
results could still be inﬂuenced by the intervention, possibly due to al-
terations of parental attitudes towards PA or heightened expectations
of children's PA levels. Accelerometry‐assessed PA is more accurate
than most self-report measures but has limitations including no infor-
mation about activity type (Corder et al., 2007). We could not assess
‘overestimation’ continuously due to dichotomous parent-classiﬁed
PA. However, the discrepancy between child PA levels and the guideline
was included in analyses, so results are independent of child PA. In fu-
ture, parents could be asked to classify their child's PA in multiple cate-
gories directly comparable to categorized objective data. However,
these results are supported by sensitivity analyses showing similar re-
sults when using 45 min to deﬁne active/inactive. The amount of over-
estimation was also similar across MVPA categories irrespective of PA
Mostparents incorrectly classify their child as meeting PA guidelines
on days when they are actually inactive. Parent support was associated
with greater parental overestimation. Strategies addressing parental
awareness of child PA may be important when designing PA promotion
interventions for children.
Conﬂict of interest statement
The authors declare that there are no conﬂicts of interest.
Data used for this study were obtained from Project MOVE/me Muevo
funded by the National Institute of Diabetes and Digestive and Kidney
Diseases (R01 DK072994). Noe C. Crespo was supported by grants
T32HL079891 and F31KD079345 and John P. Elder was supported by
NIDDK grant R01 DK072994 and partially by PRC grant U48 DP000036.
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Descriptive data for potential home and family corre lates and results of simple
three-level mixed‐ effects linear regression with potential home and family correlates
and % days of parental overestimation of child PA among 329 children and parents
from San Diego County, CA.
Potential correlate Mean (SD) or % B (95% CI) P value
3.2 (2.7) 0.8 (−0.3, 1.9) 0.14
Parental encouragement for PA
4.6 (2.2) 1.5 (0.2, 2.8) 0.02
Parent transport provision for PA
3.7 (2.3) 1.9 (0.7, 3.1) b 0.01
Parental PA with child
2.9 (2.0) 1.8 (0.4, 3.3) 0.01
Parental encouragement for
less inactivity (days/week)
4.3 (2.8) −0.8 (− 1.8, 0.2) 0.12
Total PA equipment at home
4.2 (2.0) 1.2 (−0.3, 2.6) 0.11
in bedroom (n available)
0.7 (0.4) 5.5 (−0.9, 11.9) 0.09
Child visits to PA locations
12.1 (6.0) 0.3 (−0.1, 0.8) 0.17
Number of PA locations
used≥once a week
4.0 (2.0) 0.3 (−1.1, 1.8) 0.66
Rules for PA
Do homework before going
out (% have rule)
70.4 2.8 (− 0.5, 9.1) 0.38
Stay close or within sight
of home (% have rule)
92.7 8.2 (− 2.8, 19.2) 0.14
Do not go into the street
(% have rule)
76.9 −0.2 (− 6.9, 6.6) 0.95
Do not go places alone
(% have rule)
92.4 −3.4 (− 14.1, 7.4) 0.54
Stay within neighborhood
(% have rule)
93.9 4.1 (− 7.9, 16.2) 0.50
Wear a helmet
(when biking etc.)
(% have rule)
87.8 −4.0 (− 12.7, 4.7) 0.37
Wear protective clothing
(e.g., knee pads) (% have rule)
61.6 −1.9 (− 7.7, 4.0) 0.53
Avoid strangers (% have rule) 92.4 0.9 (− 9.7, 11.6) 0.86
B, beta estimated regression coefﬁcient from three-level mixed‐effects
sion and adjusted for study condition, classiﬁcation (MVPA min) and sex with outcome
variable as % days of parental overestimation; 95% CI, 95% conﬁdence interval; PA,
Association with % days of parental overestimation.
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