The Use of a Weighted
Vest To Increase On-Task
Behavior in Children
Nancy L. VandenBerg, MS, OTR, is Occupational Therapist,
Plainwell Community Schools, Plainwell, Michigan. At the
time of this study, she was Student, Master of Science in
Occupational Therapy, Western Michigan University,
Kalamazoo, Michigan. (Mailing address: 707 S. Woodhams,
Plainwell, Michigan 49080; firstname.lastname@example.org)
This article was accepted for publication January 17, 2001.
Nancy L. VandenBerg
Key Words: attention deficit disorder with
hyperactivity • pressure • school based
The American Journal of Occupational Therapy 621
Objective. Children described as having attention deficit
hyperactivity disorder often demonstrate inability to sustain
visual attention during classroom fine motor activities. This
study investigated the effect of wearing a weighted vest
(deep-pressure sensory input) on children’s on-task behavior
in the classroom.
Method. Four students with documented attention
difficulties and hyperactivity were timed with a stopwatch
to measure their on-task behavior during fine motor activi-
ties in the classroom. All 4 students were timed for six 15-
min observations without wearing a weighted vest and for
six 15-min observations while wearing a weighted vest.
Results. On-task behavior increased by 18% to 25%
in all 4 students while wearing the weighted vest.
Additionally, 3 of the 4 students frequently asked to wear
the vest other than during the observation times.
Conclusion. These preliminary findings support the
hypothesis that wearing a weighted vest to apply deep pres-
sure increases on-task behavior during fine motor activities.
VandenBerg, N. L. (2001). The use of a weighted vest to increase
on-task behavior in children with attention difficulties. American
Journal of Occupational Therapy, 55, 621–628.
Children described as having attention deficit hyper-
activity disorder (ADHD) show “a persistent pat-
tern of inattention and/or hyperactivity-impulsivity
that is more frequent and severe than is typically observed in
individuals at a comparable level of development”
(American Psychiatric Association, 1994, p. 78). These chil-
dren often exhibit sensory processing problems such as
being easily distracted by irrelevant stimuli that is ignored
by others, frequently shifting from one uncompleted activi-
ty to another, having difficulty remaining seated when
expected to do so, performing messy written work, making
noises or talking excessively, and grabbing objects or touch-
ing things excessively.
Children with ADHD who exhibit sensory processing
problems usually cannot function effectively within the
regular classroom setting without accommodation and spe-
cial education interventions (Ayres, 1979). Such children
may be in constant motion or fatigue easily and have an
activity level that is unusually high or unusually low.
Behaviorally, these children are often impulsive, easily dis-
tractible, and exhibit a lack of planning ability. They often
cannot participate in seated activities, particularly fine
motor activities, long enough to complete tasks.
Theoretically, these children have sensory systems that are
immature and work improperly, so abnormal neural signals
are being sent to the brain cortex that interfere with “nor-
mal,” organizing brain activity (Kranowitz, 1998). The
brain, in turn, becomes overstimulated, making it difficult
for the child to organize his or her behavior and to con-
centrate (Hatch-Rasmussen, 1995). This neural sequence
often results in negative emotional responses or outbursts,
so the child with ADHD is seen as a behavior problem
(Hallowell & Ratey, 1994; Kranowitz, 1998).
Traditionally, the treatment of choice for children with
ADHD has often been medication. Medications used to
treat ADHD symptoms are believed to act on the ascend-
ing reticular activating system to help dampen some of the
activating stimuli that cause hyperactivity; medications
accomplish this by increasing the neurotransmitters
(dopamine, norepinephrine) that are suspected of being
deficient (Silver, 1993; Taylor, 1994). Serotonin levels also
have been found to be abnormally low in children with
hyperactivity and attention deficits (Gainetdinov et al.,
1999). Medication most likely affects the symptomology of
ADHD by restoring balance among the brain chemicals.
Children with attention problems are often referred to
occupational therapists for concerns regarding poor fine
motor skills as well as other adaptive problems such as con-
centration difficulties, increased levels of purposeless activi-
ty, and inability to interact successfully within the classroom
environment (Royeen & Lane, 1991). Sensory modulation
disorder is a descriptive term that occupational therapists use
to describe a person who “over responds, under responds, or
fluctuates in response to sensory input in a manner dispro-
portional to that input” (Koomar & Bundy, 1991, p. 268).
A therapeutic activity program geared toward helping chil-
dren learn to modulate their arousal levels effectively,
referred to as sensory integration treatment, is often used in
occupational therapy treatment for children with problems
resulting from ADHD (Fisher, Murray, & Bundy, 1991).
School-based therapists increasingly are using weight-
ed vests as an intervention strategy for children with con-
ditions that affect sensory modulation and attention span,
such as autism and ADHD (Joe, 1998; Maslow & Olson,
1999). Weighted vests are used as a means of applying deep
pressure, which is believed to decrease purposeless hyperac-
tivity and increase functional attention to purposeful activ-
ity (Miller, Moncayo, Treadwell, & Olson, 1999).
Farber (1982) supported a beneficial response to the
application of deep pressure, suggesting that maintained
pressure is calming as it facilitates an increase in parasym-
pathetic or relaxed tone. In describing her own autism,
Temple Grandin related her experience of severe anxiety
and how deep pressure ultimately helped her reduce the
anxiety’s debilitating effects by reducing overall arousal and
facilitating attention and awareness (Grandin & Scariano,
1986). In studies done with children with autism, deep
pressure has been found to have a calming effect (Edelson,
Edelson, Kerr, & Grandin, 1999; Krauss, 1987; McClure
& Holtz-Yotz, 1991; Miller et al., 1999; Zissermann,
1992). No published studies on the effects of deep pressure
with children with ADHD were found.
Proprioception and deep touch-pressure are types of
sensory information that can produce a calming effect
(Ayres, 1972; Farber, 1982; Knickerbocker, 1980). Both
are carried by the dorsal column system to higher levels in
the thalamus and the reticular formation and then up to
sensory areas in the parietal lobe of the cerebral cortex.
According to Royeen and Lane (1991), “Since the reticular
formation mediates arousal, the reticular projections of the
dorsal column pathway may be related to the efficacy of
these inputs in decreasing arousal and producing calming”
(p. 115). The dorsal column system also has some connec-
tions with the limbic system via the hypothalamus and the
anterolateral system. This functional redundancy in the
nervous system may play a role in the efficacy of sensory
integration intervention (Fisher et al., 1991).
An example of the nervous system’s functional redun-
dancy is seen in the registration of deep pressure. Deep
pressure is registered in the limbic system, hippocampus,
and reticular activating system and may stimulate produc-
tion of neurotransmitters to modulate arousal levels, simi-
lar to the effects of medications. The action of the
neurotransmitters norepinephrine, epinephrine, and sero-
tonin is associated with the limbic structures and compo-
nents of the reticular system, hypothalamus, and cortex
(Ashton, 1987). Medications allow more of these neuro-
transmitters to be available to the brain, influencing the
level of arousal in the nervous system of a child and there-
by controlling hyperactivity and helping to increase the
child’s ability to attend (Cohen, 1998; Hallowell & Ratey,
1994). The reticular system is aroused to varying degrees of
alertness by sensory stimuli (Ayres, 1972), and touch-pres-
sure appears to be particularly effective in dampening over-
ly activating stimuli.
Deep pressure also sends sensory information into the
Purkinje cells in the cerebellum, which then work to damp-
en stimulation entering the reticular formation through
brain chemistry or neurotransmitters (Hanschu, 1998;
Reeves, 1998). Purkinje cells are rich in serotonin and are
responsible for inhibition of motor activity (Edelson, 1995).
Children with ADHD have been found to have high levels
of hyperactivity related to lower levels of serotonin in their
blood (Gainetdinov et al., 1999; Taylor, 1994). Deep pres-
sure may stimulate the increase in serotonin, as well as other
neurotransmitters, to create a natural calming on the central
nervous system in the child with ADHD.
Weighted vests can provide deep, sustained pressure.
Current school-based occupational therapy practice in the
United States often incorporates the use of weighted vests to
increase children’s attention to school-based tasks (Joe,
1998; Maslow & Olson, 1999). The vests can be construct-
ed inexpensively from materials that are attractive and do
not stand out as a “therapeutic garment” so that the child
does not look different from his or her peers. Vests can be
administered by teachers (under the guidance of an occupa-
622 November/December 2001, Volume 55, Number 6
tional therapist) without removing the child from the class-
room setting. They can be worn during purposeful activity
within the child’s learning environment, and children can
even don the vests themselves. According to Hanschu
(1998), “The right sensation, in the right amount, at the
right time, can profoundly influence arousal, alertness,
attention, and how ably a person makes adaptive responses
all day long” (p. 1). As Farber (1982) pointed out, however,
when using maintained pressure on any part of the body,
deciding how long and how often to apply the pressure is
difficult. A more rigorous analysis is needed to measure the
clinical effects of using a weighted vest to apply deep pres-
sure for the purpose of increasing on-task behavior. Such
analysis would help in determining the overall effectiveness
of using such a vest to increase attention to purposeful activ-
ity and contribute to evidence-based practice (Abreu,
Peloquin, & Ottenbacher, 1998). The purpose of this study
was to measure on-task behavior in children with attention
difficulties while wearing a weighted vest calibrated at 5% of
each child’s body weight for a 15-min period while engaged
in classroom fine motor activities.
A convenience sample of 4 children receiving school-based
occupational therapy services was selected for the study.
The children had been diagnosed as having ADHD by a
physician or scored in the high/problems range on the
hyperactivity and attention scales of the Conners’ Teacher
Rating Scales (CTRS-39; Conners, 1989). The CTRS-39
requires that the teacher rate a student on 39 behavioral
items from observations in multiple settings (playground,
classroom, lunch) from which standard methods are used
to derive Tscores for the student. A Tscore of 65 or more
indicates a high/problem area. The scales were scored by
the school social worker and made available for the parents
to share with their physician to help in making a determi-
nation of ADHD.
The 4 children selected for the study attended school
in a Midwestern rural school district. Their ages ranged
from 5 years, 9 months to 6 years, 10 months. During the
previous academic year, all these students had attended spe-
cial education or at-risk preschool programs in which
developing school-readiness skills had been the primary
goal. Students 1 and 2 were girls and eligible for special
education services as speech and language impaired.
Students 3 and 4 were boys and eligible for special educa-
tion services as physically or otherwise health impaired due
to ADHD as diagnosed by a physician. Before as well as
during the study, Student 3 received medication as pre-
scribed by his physician.
All 4 students received school occupational therapy
services. The occupational therapist described each child as
having a sensory modulation problem exhibited by exces-
sive movement (constant playing with hair or clothing,
picking at body parts such as nails, reaching or playing with
objects excessively, unnecessarily getting in and out of the
seat, rolling on the floor), overreaction to extraneous stim-
uli, and inability to complete an activity successfully.
According to the occupational therapy clinical evaluation
and as observed within the classroom, all 4 students had
considerable difficulty writing their first names within the
spaces of 1-in. ruled paper and had difficulty writing letters
so that they rested on a line. When coloring, all 4 students
did not stay within boundaries of simple shapes, and cut-
ting did not remain on the lines of simple shapes.
The children were timed for on-task behavior while
engaged in classroom fine motor activities, and data were
recorded in the baseline phase and intervention phase.
Varied activities such as coloring pictures, cutting shapes
and gluing them onto paper, writing letters of the alphabet
within squares on paper, counting out small objects accord-
ing to a designated number, and stringing beads were typ-
ical table-top activities performed during the timed
Weighted vests. Denim vests that buttoned down the front
were purchased inexpensively from a thrift shop. Pockets
from old jeans were removed and sewn into the inside of
the vests so that weights could be placed into the pockets
and would be evenly distributed. The pockets were posi-
tioned high enough on the chest anteriorly to prevent the
weights from resting on the child’s hips or legs when seat-
ed. A pocket was positioned posteriorly between the scapu-
lae just below the scapular borders to ensure that the weight
was supported from the shoulder girdle. The placement of
the weights higher up on the shoulder girdle rather than
predominately below chest level has been used successfully
by other therapists (Hanschu, 1999). Weights were pur-
chased in 1/2-lb, 3/4-lb, and 1-lb fabric pouches and
placed into the interior pockets so that they were evenly
distributed front and back, with a total weight as close to
5% of the child’s body weight as possible.
Stopwatches. Two dependable stopwatches and a timer
set at 15 min were used.
Recording sheets. The total time a child spent on task
during an activity was recorded to the hundredth of a sec-
ond. The student number, date, and activity the class was
instructed to perform for each observation were recorded.
Consent forms. Written permission to carry out the
study was obtained from the special education supervisor
of the school district. Parents signed consent forms autho-
rizing their children to participate in the study after the
purpose of the research was explained to them.
The study was a quasi-experimental, single-system, AB
The American Journal of Occupational Therapy 623
design (Bloom, Fischer, & Orme, 1995; Ottenbacher &
York, 1984). All prescribed medications and special edu-
cation services that the students were eligible to receive,
such as occupational therapy and speech–language ser-
vices, continued as normally scheduled during the baseline
and intervention phases. The study was initiated after the
beginning of the second school semester so that the chil-
dren would be familiar with classroom activities, proce-
dures, and expectations.
Two observers were used in the study. One observer
was the author who was also the occupational therapist for
the students at the study site. The other observer was an
occupational therapy fieldwork student. Before beginning
the study, the two observers randomly selected 11 nonpar-
ticipant students and practiced timing them performing
the same types of classroom fine motor tasks as those timed
in the baseline and intervention phases of the study. On-
task behavior was defined as engagement in those process-
es that were necessary to complete the activity assigned by
the teacher and were a part of the expected process. A child
was timed as being on task while visually focused on the
activity and engaging in the processes to complete the
activity, such as reaching for required materials (scissors,
crayons, etc.) as needed. Handling or reaching for materi-
als no longer needed was timed as off task. Dropping some-
thing on the floor was allowed once but was timed as off
task if more frequent. Talking to other children, unless con-
tinuing to work, was timed as off task. Interater agreement
was defined as the observers being within 10 sec of one
another in their timed observation of a child’s on-task
behavior. Practice timings with the 11 nonparticipant chil-
dren were completed, with the last 6 consecutive timings
being within 10 sec of one another.
The occupational therapist-observer showed the vests
to each child on a day before observations began. The ther-
apist fit the vest to each child, weighing the child so that
the weights could be calibrated to 5% of his or her weight
as closely as possible, and ensured no distress to the shoul-
der girdle or posture. The children were asked whether the
vest felt comfortable and whether they would wear it in the
classroom when the teacher asked them to wear it along
with some other children. They were not told the purpose
of the vest nor that they would be timed while wearing it.
Another volunteering child was given an unweighted vest
to wear at the same time in the classroom so that the chil-
dren in the study would not feel singled out. The children
were also given the vest to wear at times other than during
the observation periods so that they would not learn that
putting on the vest meant that they would be observed or
to “try” and be especially on task.
The observers spent time within the two study class-
rooms before beginning the baseline phase so that the chil-
dren would not be distracted by their presence. The
baseline phase spanned six different days within a 15-day
period during which on-task behavior (dependent variable)
was measured in seconds during a 15-min activity, totaling
six observations for each child. The children were observed
at different assigned times in accordance with their sched-
ule of attendance (morning or afternoon kindergarten,
preprimary). Each child’s scheduled observation time was
maintained throughout the study during the six baseline
and six intervention observations.
Timings began after the teacher had given instructions
to the class. Observations were recorded during a table-top
activity while the child was engaged in organizing materi-
als, drawing, coloring, writing, pasting, or cutting as the
teacher had instructed. One observer timed each child’s on-
task behavior during the baseline phase, and the other
observer timed each child’s on-task behavior during the
intervention phase without knowledge of the baseline out-
comes. The total time on task during each 15-min period
was recorded as well as the name of the activity assigned
that particular day.
The intervention phase followed in which observations
were also completed within 15 days. During the interven-
tion phase, the 4 students wore a weighted vest and was
timed by the other observer for six 15-min periods as
described in the baseline phase. Each child’s vest was put on
5 min before the beginning of the timing and removed
after the completion of the 20-min to 30-min activity in
which they were involved. Informal interviews with the
classroom teachers and aides also were conducted to pro-
vide additional qualitative information regarding the out-
comes of using the vest.
Two methods of data analysis were used in this study to
combine the strengths of several methods while avoiding
some of their limitations (Bloom et al., 1995). The 2–stan-
dard deviation band approach (Bloom et al., 1995;
Gottman & Leiblum, 1974; Ottenbacher & York, 1984)
was chosen as a good fit because it is most useful with a rel-
atively small number of baseline observations and the same
number of intervention observations with some fluctuation
in the baseline data but with no stable pattern present
(Bloom et al., 1995). Because the study involved fewer
than seven baseline observations, however, it was safer to
assume that the data were autocorrelated (Bloom et al.,
1995), as there could be some growth expected in attention
over time due to practice or maturity (in spite of design
precautions). Furthermore, transformation of data to
remove autocorrelation, if present, could result in loss of
data. Thus, to take into account the possibility that the data
might be autocorrelated and not independent as assumed
in the 2-standard deviation method, the celeration line
approach was used to determine statistical significance
because it is a better fit when autocorrelation of data is pre-
624 November/December 2001, Volume 55, Number 6
sent (Bloom et al., 1995). The celeration line also takes any
trends in the baseline into account.
Figure 1 represents the results of the data collected dur-
ing the baseline phase and the intervention phase when the
students were wearing the weighted vests while performing
fine motor activities within the classroom. A mean number
of minutes that each child was on task were computed for
the baseline. The values associated with 2 standard devia-
tions above the baseline mean were determined, with a hor-
izontal line drawn on the scatterplot of each child’s data
representing this value. The lines are extended into the
intervention phase to determine whether at least two con-
secutive observations (data points) during the intervention
phase fell above the 2-standard deviation line (+2SD)
(Gottman & Leiblum, 1974). Using the 2-standard devia-
tion band method of analysis, all students except Student 2
demonstrate 2 consecutive data points above +2SD, indi-
cating that a significant change (p< .05) occurred from the
baseline phase to the intervention phase for Students 1, 3,
Additionally, a celeration line was also computed
using median scores in the baseline (Gingerich &
Feyerherm, 1979) and extended into the intervention
phase; the extension predicts what course the students’ on-
task behavior would take in the absence of any interven-
tion. Statistically, a significant change has occurred in the
intervention phase if the required proportion of data points
above the celeration line in that phase is sufficiently differ-
ent from the number above the celeration line in the base-
line phase. To represent a significant increase at the .05
level (Bloom et al., 1995), Students 1 and 2 needed 6 data
points to be above the celeration line; Student 3 needed 5;
and Student 4 needed 4. As seen in Figure 1 for all 4 stu-
dents, the criteria of the necessary number of data points
falling above the celeration line to indicate a significant
change in the intervention phase at the .05 level was met.
Ottenbacher and York (1984) cautioned that statistical
analysis of data from single-system designs should be inter-
preted as an adjunct to visual analysis because the presence
of serial dependency or unusual trends may compromise
results. Although serial dependency and the presence of
trends have been taken into consideration by using both
the celeration line and 2-standard deviation band methods
of analysis, visual analysis further supports the results that
a significant change in on-task behavior occurred during
the intervention phase. All 4 students showed a regressing
trend line in Figure 1, but Students 2 and 3 appear to be
getting significantly worse over time as illustrated by the
steeper downward slope of the trend line. Only during the
intervention phase with the use of the vest did any on-task
behaviors measure more than 2 standard deviations above
the mean, showing an upward trend.
The change from the baseline phase to the interven-
tion phase with Student 1 indicates a 25% mean increase
in the amount of time that this student was on task while
wearing the vest (see Figure 2). The change from the base-
line phase to the intervention phase with Students 2, 3, and
4 indicates a mean increase of 17% to 18% in on-task
behavior while wearing the vests. Student 1’s (female, no
medication) mean time spent on task during the baseline
phase was only 54% and increased to a mean of 79% while
wearing the weighted vest. Student 2 (female, no medica-
tion) demonstrated a mean on-task behavior of 63% dur-
ing the baseline with an increase to 81% while wearing the
vest. Student 3 (male, and receiving medication at the same
scheduled time during both phases) demonstrated a mean
of 64% for on-task behavior during the baseline phase,
increasing to 82% while wearing the vest. Student 4 (male,
no medication) showed a baseline mean of 64% with an
increase to a mean of 81% for on-task behavior while wear-
ing the vest.
Perhaps the most revealing questions to raise are those that
are hard to answer with quantitative research methods.
However, these questions give us a view of the child’s reali-
ty and the meaning the intervention has for the child. Yerxa
(1987) suggested that “the research subject might be one of
the most important sources of information” (p. 417). The
teachers reported that 3 of the 4 students (1, 3, 4) asked to
wear the vest at times other than during the timed obser-
vations and wanted to put the vest on themselves. Student
3 asked to wear the vest during an occupational therapy
treatment session (after completion of the study). The vest
that was fitted to him for the study was not available in the
occupational therapy room, so the therapist gave him
another vest with less weight in it. He responded that this
vest “did not have the same amount of weight in it,”
appearing to be aware of the difference in a 1/2 lb of pres-
sure on his body. When asked why he wanted to wear the
vest, Student 3 responded, “I like to wear the vest. It’s com-
fortable.” Student 4 wanted to keep the vest on after one
observation was completed, and he had been wearing it for
20 min. He told the observer that the vest “made him feel
good.” Student 1 asked to wear the vest every day when she
came into the kindergarten class, and the teacher believed
that the student would have liked to have worn it all day.
This child was observed to be the most hyperactive of the
study group and demonstrated the greatest increase in on-
task behavior while wearing the vest.
Yerxa (1987) also suggested that we “need to ask ques-
tions about how children relate to their peers, the nature of
their play, and how satisfied they are with what they do” (p.
416). The classroom staff members for Students 1, 2, and 3
commented to the occupational therapist-observer that they
noticed a visible difference in all 3 students, especially in
Student 1. One support staff member commented that “the
The American Journal of Occupational Therapy 625
vests really help the kids during centers [seated, fine motor
activities]” and that “the vest especially kept [Student 1] in
her seat.” A staff member from the after-kindergarten
school program asked to use the vest with Student 3, com-
menting that it seemed to help him organize himself on the
playground and not run around so purposelessly; he seemed
to be “slowing down more and stopping to think” when
wearing the vest and to be interacting with other children
more appropriately. She observed that without the vest,
Student 3 “was just all over the room.”
Yerxa (1991) stressed that in occupational therapy, a need
exists “to emphasize the skills and capabilities of the whole
person and include the experience of engagement in occu-
pation” (p. 201). This study attempted to measure the level
of engagement in occupation of 4 students 5 to 6 years of
age with attention difficulties by measuring on-task behav-
ior while performing fine motor activities within their nat-
ural environment—the classroom. Weighted vests were
used to apply deep-pressure sensory input and measure
whether it changed on-task behavior.
Although a small sample size was used, the behavioral
results indicate a clinically significant increase in on-task
behavior in all 4 students while wearing a vest containing
weights totaling 5% of their individual body weight. All 4
students demonstrated significant changes at the .05 level in
on-task behavior while wearing the weighted vests according
to the celeration line method of analysis. Students 1, 3, and
4 showed a significant change at the .05 level according the
2-standard deviation band method of analysis.
These findings strongly suggest the need for further
inquiry. Videotaping, as suggested by Miller et al. (1999),
was not used so as not to distract the children or make
them feel self-conscious. It is very important to watch the
entire observation period than in intervals. Observing the
entire activity allows the observer to determine quickly
whether the child’s actions are on task as part of the activi-
ty or are purposeless, off-task behaviors that might be mis-
interpreted as on task if the sequence of the activity is not
carefully observed in its entirety.
The AB design was used instead of the ABA design
because of ethical concerns with discontinuing the vests,
which appeared to be an effective intervention. Hence, the
design limits this study’s generalizability. Use of an ABA or
alternating treatment design would further add to the
power of a follow-up study and strengthen the validity of
results by decreasing the effects of variables such as matu-
626 November/December 2001, Volume 55, Number 6
Figure 1. The 2-standard deviation band method is used to evaluate changes in minutes spent on task during a fine motor activ-
ity from the baseline phase to the intervention phase during which a weighted vest was worn. Two consecutive data points above
the +2SD band during the intervention phase indicates a change at the .05 level. The celeration line method requires (for
level change) 6 data points above the celeration line during the intervention phase for Students 1 and 2, 5 data points for Student
3, and 4 data points for Student 4.
ration or practice. Another limitation of this study is the
small sample size. Future research using a larger sample size
would increase generalizability, and an increase in age range
would increase the generalizability of the findings to other
age groups. Future studies can help to determine how dif-
ferent amounts of weight affect on-task behavior by using
the 2-standard deviation method.
The use of a weighted vest as a means of applying deep-
pressure sensory input is practical and convenient for class-
room use. It is low cost and easily transported to therapy
sessions with occupational therapists and speech–language
therapists and for use in other learning environments where
optimal on-task behavior is required for maximal learning.
This study supports the efficacy of using weighted
vests on children with attention difficulties to increase on-
task behavior. A significant increase (p< .05) in on-task
behavior was demonstrated in 4 students when the weight-
ed vests, calibrated at 5% of their individual body weight,
were used during the intervention phase. ▲
I thank Debra Lindstrom-Hazel, PhD, OTR, for her assistance through-
out the project and Richard G. Cooper, EdD, OTR, for his comments on
earlier drafts of this article. I also thank the students’ teachers MaryBeth
Ramm and Mary Warner, Plainwell Community Schools, for their
cooperation in the research and Sheryl Lee (former occupational thera-
py student at Western Michigan University) who participated as one of
the observers in this study. This research was completed as partial ful-
fillment of a master’s in occupational therapy at Western Michigan
Abreu, B., Peloquin, S. M., & Ottenbacher, K. (1998).
Competence in scientific inquiry and research. American Journal of
Occupational Therapy, 52, 751–759.
American Psychiatric Association. (1994). Diagnostic and statistical
manual of mental disorders (4th ed.). Washington, DC: Author.
Ashton, J. (1987). Brain disorders and psychotropic drugs. New York:
Oxford University Press.
Ayres, A. J. (1972). Sensory integration and learning disorders. Los
Angeles: Western Psychological Services.
Ayres, A. J. (1979). Sensory integration and the child. Los Angeles:
Western Psychological Services.
Bloom, M., Fischer, J., & Orme, J. (1995). Evaluating practice:
Guidelines for the accountable professional. Boston: Allyn & Bacon.
Cohen, C. W. (1998). The attention zone: A parent’s guide to atten-
tion deficit/hyperactivity disorder. Washington, DC: Taylor & Francis.
Conners, C. K. (1989). Conners’ Teacher Rating Scales. New York:
Edelson, S. M. (1995). Self-injurious behavior. Salem, OR: Center
for the Study of Autism. Retrieved July 10, 1998, from the World Wide
Edelson, S. M., Edelson, M. G., Kerr, D. C. R., & Grandin, T.
(1999). Behavioral and physiological effects of deep pressure on children
with autism: A pilot study evaluating the efficacy of Grandin’s hug
machine. American Journal of Occupational Therapy, 53, 145–152.
Farber, S. D. (1982). Neurorehabilitation: A multisensory approach.
Fisher, A. G., Murray, E. A., & Bundy, A. C. (Eds.). (1991).
Sensory integration: Theory and practice. Philadelphia: F. A. Davis.
Gainetdinov, R. R., Wetsel, W. C., Jones, S. R., Levin, E. D., Jaber,
M., & Caron, M. G. (1999, January 15). Role of serotonin in the para-
doxical calming effect of psychostimulants on hyperactivity. Science,
Gingerich, W., & Feyerherm, W. (1979). The celeration line tech-
nique for assessing client change. Journal of Social Service Research, 3(1),
Gottman, J. M., & Leiblum, S. R. (1974). How to do psychothera-
py and how to evaluate it. New York: Holt, Rinehart, & Winston.
Grandin, T., & Scariano, M. M. (1986). Emergence: Labeled autis-
tic. Novato, CA: Arena Press.
Hallowell, E. M., & Ratey, J. J. (1994). Driven to distraction. New
York: Random House.
Hanschu, B. (1998, March). Creating sensory diets. Course and
paper presented at the Spring Conference for the Michigan Alliance of
School Physical and Occupational Therapists, Lansing, Michigan.
Hanschu, B. (1999, April). Sensory issues in autism. Course pre-
sented at the Spring Conference for the Michigan Alliance of School
Physical and Occupational Therapists, East Lansing, Michigan.
Hatch-Rasmussen, C. (1995) Sensory integration. Salem, OR:
Center for the Study of Autism. Retrieved July 10, 1998, from the
World Wide Web: http://www.autism.org/si.html
Joe, B. E. (1998, May 21). Are weighted vests worth their weight?
OT Week, 12, 12–13.
Knickerbocker, B. M. (1980). A holistic approach to learning dis-
abilities. Thorofare, NJ: Slack.
Koomar, J. A., & Bundy, A. C. (1991). Tactile processing and sen-
sory defensiveness. In A. G. Fisher, E. A. Murray, & A. C. Bundy (Eds.),
Sensory Integration: Theory and practice (pp. 251–314). Philadelphia:
F. A. Davis.
Kranowitz, C. S. (1998). The out-of-sync child: Recognizing and cop-
ing with sensory integration dysfunction. New York: Skylight Press.
Krauss, K. E. (1987). The effects of deep pressure touch on anxi-
ety. American Journal of Occupational Therapy, 41, 366–373.
Maslow, B., & Olson, L, (1999, April). Findings of a nationwide
survey about occupational therapy practice with weighted vests. Paper pre-
sented at the American Occupational Therapy Association Annual
Conference and Exposition, Indianapolis, Indiana.
McClure, M. K., & Holtz-Yotz, M. (1991). Case Report—The
effects of sensory stimulatory treatment on an autistic child. American
Journal of Occupational Therapy, 45, 1138–1142.
Miller, A., Moncayo, Z., Treadwell, D., & Olson, L. (1999, April).
Children with autism using weighted vests: Two single-subject studies. Paper
presented at the American Occupational Therapy Association Annual
Conference and Exposition, Indianapolis, Indiana.
Ottenbacher, K., & York, J. (1984). Strategies for evaluating clini-
cal change: Implications for practice and research. American Journal of
The American Journal of Occupational Therapy 627
Figure 2. The mean percentage of time on task during the
baseline phase (without the weighted vest) and the interven-
tion phase (with the weighted vest).
Percentage of Time on task
Occupational Therapy, 38, 647–659.
Reeves, G. D. (1998, October). Brain gain: Prenatal and postnatal
neural development. Course presented at the Full Conference for the
Michigan Alliance of School Physical and Occupational Therapists,
Royeen, C. B., & Lane, S. J. (1991). Tactile processing and senso-
ry defensiveness. In A. G. Fisher, E. A. Murray, & A. C. Bundy (Eds.),
Sensory Integration: Theory and practice (pp. 108–136). Philadelphia: F.A.
Silver, L. B. (1993). Dr. Larry Silver’s advice to parents on attention-
deficit hyperactivity disorder. Washington, DC: American Psychiatric Press.
Taylor, J. F. (1994). Helping your hyperactive/attention deficit child.
Rocklin, CA: Prima Publishing.
Yerxa, E. J. (1987). Nationally Speaking—Research: The key to the
development of occupational therapy as an academic discipline.
American Journal of Occupational Therapy, 41, 415–419.
Yerxa, E. J. (1991). Nationally Speaking—Seeking a relevant, eth-
ical, and realistic way of knowing for occupational therapy. American
Journal of Occupational Therapy, 45, 199–204.
Zissermann, L. (1992). Case Report—The effects of deep pressure
on self-stimulating behaviors in a child with autism and other disabili-
ties. American Journal of Occupational Therapy, 46, 547–551.
628 November/December 2001, Volume 55, Number 6