September 2007, Vol 97, No. 9 | American Journal of Public Health Farley et al. | Peer Reviewed | Research and Practice | 1625
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RESEARCH AND PRACTICE
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Objectives. We evaluated the effect of providing a safe play space on the phys-
ical activity level of inner-city schoolchildren.
Methods. In 1 of 2 matched neighborhoods, we opened a schoolyard and pro-
vided attendants to ensure children’s safety. Over the next 2 years we directly
observed the number of children and their physical activity levels in the school-
yard, as well as in the surrounding intervention and comparison neighborhoods.
We also surveyed children in the schools in the intervention and comparison
neighborhoods regarding sedentary activities.
Results. After the schoolyard was opened, a mean of 71.4 children used it on
weekdays and 25.8 used it on weekends during the school year. When observed,
66% of these children were physically active. The number of children who were
outdoors and physically active was 84% higher in the intervention neighborhood
than the comparison neighborhood. Survey results showed that children in the
intervention school reported declines relative to the children in the comparison
school in watching television, watching movies and DVDs, and playing video
games on weekdays.
Conclusion. When children were provided with a safe play space, we observed
a relative increase in their physical activity. Provision of safe play spaces holds
promise as a simple replicable intervention. (Am J Public Health. 2007;97:
1625–1631. doi:10.2105/AJPH.2006.092692)
Safe Play Spaces To Promote Physical Activity in Inner-City Children:
Results from a Pilot Study of an Environmental Intervention
| Thomas A. Farley, MD, MPH, Rebecca A. Meriwether, MD, MPH, Erin T. Baker, MS, Liza T. Watkins, MA, Carolyn C. Johnson, PhD, and Larry S. Webber, PhD
Institute of Medicine recognizes that children
need more opportunities for physical activity
and has recommended that schools be used
as community centers for physical activity
during afterschool hours.
18
In spite of the recognition of environmental
effects, few interventions have been devel-
oped that increased physical activity or re-
duced obesity in children by changing their
environment. We implemented a pilot inter-
vention in which we provided a safe play
space in a low-income, inner-city neighbor-
hood and evaluated its effect on the physical
activity of local children.
METHODS
Setting
Our study took place in 2 low-income
neighborhoods in New Orleans that were ap-
proximately 1 mile apart but were separated
by a canal. According to the 2000 census,
the intervention and comparison neighbor-
hoods were similar for median household
income ($19185 and $21297 per year,
respectively), percentage of African Ameri-
cans (99% and 90%), and percentage of
households headed by women (both 37%);
the intervention neighborhood had a slightly
lower population density (10144 vs 14717
residents per square mile, respectively). Each
neighborhood had a district public elemen-
tary school with a schoolyard, which (before
the study) was locked when the school was
not in operation. The catchment districts for
the 2 schools were such that nearly all stu-
dents lived within 0.5 miles of their respec-
tive neighborhood school. The intervention
school taught children in prekindergarten
through sixth grades, and the comparison
school taught children in prekindergarten
through fifth grades. In both schools, more
than 99% of the children were African
American. The intervention school had a
higher “school performance score” than the
comparison school (69.6 vs 38.3, respec-
tively), a composite measure based on stan-
dardized test scores and attendance for
which the highest performing schools in the
city scored 130.
The prevalence of overweight is rising rap-
idly in children.
1
Among African Americans
the problem is severe: 21.8% of African
American children aged 12 to 19 years are
overweight.
1
The relation between inade-
quate physical activity and weight gain is
strong and consistent.
2,3
In spite of national
recommendations for greater physical activ-
ity, American children engage in low levels
of physical activity.
4,5
There is increasing evidence that features
of physical and social environments influence
levels of physical activity.
6–9
A sense of safety
in the neighborhood appears to be one im-
portant environmental determinant. Adults
who perceive their neighborhoods to be un-
safe are substantially more likely to be physi-
cally inactive than are adults who perceive
their neighborhoods as safe.
10
Outdoor safety
is especially important for children, because
time spent outdoors is strongly associated
with physical activity.
11 , 12
Parents rank safety
as the most important factor in deciding
whether to let their young children play in a
given location.
13
A recent study found that
children whose parents perceived their neigh-
borhoods to be particularly unsafe were more
than 4 times as likely to be obese than chil-
dren whose parents perceived their neighbor-
hoods to be safe.
14
Changes in family structure and work have
accentuated the effect of neighborhood
safety on physical activity. The proportion of
children whose mothers are employed out-
side the home has increased in recent dec-
ades. Although preschool children whose
mothers work often attend structured day-
care programs or are cared for by relatives,
23% of school-aged children whose mothers
are employed outside the home are left alone
during afterschool hours.
15
One multisite
study found that when children are in self-
care, their most frequent activity by far is
watching television,
16
a sedentary activity
that is strongly associated with obesity.
17
The

American Journal of Public Health | September 2007, Vol 97, No. 91626 | Research and Practice | Peer Reviewed | Farley et al.
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RESEARCH AND PRACTICE
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Intervention
The intervention took place between April
2003 and May 2005 and consisted of provid-
ing a safe, supervised schoolyard where chil-
dren could engage in nondirected play. On
days when school was in session, the school-
yard was open from school dismissal time,
usually 3:00 PM, until 5:30 PM or dark. It was
open on Saturdays from 10:00 AM until 3:00
PM and on Sundays from 12:00 PM until 3:00
PM. By April 2004, the Sunday session was
discontinued because of low attendance. Dur-
ing the summer of 2003, the schoolyard was
open on the same days and hours as during
the school year. During the summer of 2004,
the schoolyard was open on this same sched-
ule until it was closed on July 10 and then re-
opened at the beginning of the next school
year. The schoolyard at the comparison school
remained locked when school was not in ses-
sion until January 2005 when another pro-
gram began to use that location for a small
limited-enrollment afterschool program.
Any child who had written parental per-
mission and either was in second grade
through eighth grade or was in kindergarten
or first grade and was accompanied by an
older sibling or parent was allowed to use the
intervention schoolyard during its hours of
operation, regardless of whether he or she
attended the school. No fees were charged.
Children were required to check in with an
attendant when they entered the yard each
day to verify parental permission, but after-
ward they could enter and exit freely. Three
to 4 attendants (almost all of whom were
teachers) were paid to prevent fights or bully-
ing among children, prevent vandalism or
theft of recreational equipment, and prevent
adults or children outside of the designated
age range from entering the schoolyard. At-
tendants did not organize, require, or even
suggest specific activities to children. Parents
could accompany their children in the school-
yard, but almost none did. To address liability
concerns, the project purchased additional lia-
bility insurance for the school, at a cost of
$550 per year. The cost for 12 months of sal-
aries, for all of the attendants and a custodian
when school was not in session, was $49000,
which was paid by the research project.
The intervention schoolyard was approxi-
mately 5800 m
2
in size. It included an installed
play structure with impact-absorbent surfac-
ing, large paved areas in which basketball
hoops were stationed and a 4-square court
was painted, and an open grassy field. The re-
search project provided and maintained ample
sports equipment such as footballs, basket-
balls, playground balls, hula hoops, jump
ropes, Frisbees, and parachutes. A compact
disk player and radio was also provided to
supply music for dancing, and a sprinkler was
installed during the summer months.
Evaluation
Attendance. The number of children who
used the schoolyard was taken from atten-
dance records kept by schoolyard staff.
Physical activity. We measured by direct
observation the number of children and their
physical activity levels in the schoolyard and
in the neighborhoods surrounding each
school. Observations occurred after school on
5 randomly selected weekdays and 4 ran-
domly selected weekend days during a
4-week period before the intervention began
and during each quarter (every 3 months)
throughout most of the intervention period
(April 2003–October 2004). During the last
2 quarters (November 2004–January 2005
and February–April 2005) observations were
increased to 10 randomly selected weekdays
(2 for each weekday) and 2 randomly se-
lected Saturdays.
The physical activity of the children in the
schoolyard during the designated hours was
assessed using a modified version of the Sys-
tem of Observing Play and Leisure Activity in
Youth.
19 , 2 0
The system involves momentary
time-sampling in which periodic scans in a
target area are made according to an estab-
lished schedule. At each scan and in each
target area, counts are made of the number
of children who are engaged in each of 3
different levels of physical activity: sedentary
(lying, sitting, or standing), walking, or very
active (e.g., running, jumping rope, climbing
on play equipment). Two observers used me-
chanical counters mounted on boards and
independently counted boys and girls at each
activity level; their results were averaged.
We developed a modification of the System
of Observing Play and Leisure Activity in
Youth to measure physical activity of children
in the neighborhoods that surrounded the
schoolyards. For each neighborhood we de-
fined a “Neighborhood Measurement Area”
of 8 blocks by 8 blocks (approximately two
thirds of a mile by two thirds of a mile area)
that surrounded the school; the areas approxi-
mated 2 census tracts in the intervention area
and 3 census tracts in the control area. In
each Neighborhood Measurement Area, a
driver and an observer drove at 10 mph or
slower on standard routes that traversed
every street oriented north–south. An ob-
server in the passenger seat identified chil-
dren outdoors both on the streets that were
traveled and on the cross-street blocks to the
east of all intersections. Children playing in
backyards could not be observed and were
thus not included in the measurement. Each
identified child who appeared to be in the tar-
get age range (second through eighth grade)
was counted and coded according to the
child’s activity level. In the comparison neigh-
borhood, the areas observed included the
comparison schoolyard.
To control for the effect of weather on out-
door activity, we scheduled observations so
that they occurred simultaneously in the in-
tervention and comparison neighborhoods, as
well as in the intervention schoolyard. To con-
trol for interobserver bias, we rotated 3 ob-
server teams among the neighborhoods and
the intervention schoolyard. To assess the in-
terobserver reliability of the method, we con-
ducted 16 paired observations from the same
car driving through intervention and compari-
son neighborhoods. The intraclass correlation
coefficient of the observers’ counts of active
children was 0.962.
Sedentary activities. To assess the effect of
the intervention on sedentary activities, we
conducted annual self-report surveys of chil-
dren. For practical reasons, these surveys
were conducted with children in the second
through fifth grades who were enrolled in the
schools in the intervention and comparison
neighborhoods. All children in these grades
who had written parental consent and were
available in school were surveyed. Surveys
were administered simultaneously in inter-
vention and comparison schools on Tuesdays
in March or April. Students were asked about
activities during the previous afternoon and
evening, on the previous Saturday morning,
and on the previous Saturday afternoon and