Journal of Pediatric Psychology, Vol. 21, No. 5, 1996, pp. 659-670
Additive Benefits of Laxative, Toilet Training, and
Biofeedback Therapies in the Treatment of Pediatric
Encopresis1
Daniel J. Cox,2 James Sutphen, William Ling, Warren Quillian, and Steve
Borowitz
University of Virginia Health Sciences Center
Received May 12, 1995; accepted February 20. 1996
Compared the additive benefits of laxative, behavior, and biofeedback treatments
for encopresis, while attempting to identify treatment mechanisms and predictors
of treatment outcome. 44 encopretic children, ages 6-15 years, were randomly
assigned to either laxative therapy (LAX), LAX plus enhanced toilet training
(ETT), or LAX + ETT + anal sphincter biofeedback (BF). Daily symptom
diaries were completed 14 days before, upon initiation of, and 3 months following treatment initiation. ETT and BF were superior to LAX in reducing encopresis. Outcome was significantly predicted by improvement during the initial
14 days of treatment. Reduction of soiling was associated with an increase in
bowel movement frequency, and reductions in defecation pain and parental
prompting to use the toilet. Because of its efficacy and minimal reliance on
technology, ETT should be the initial treatment of choice.
KEY WORDS: encopresis; laxatives; behavior therapy; biofeedback; prediction.
The DSM-IV (American Psychiatric Association, 1994) defines encopresis as
involuntary bowel movements, in inappropriate places, at a frequency of at least
once a month for at least 3 months, for children ages 4 and older. With this
'We thank the National Institutes of Health for supporting this grant (ROl HD 28160), Dr. LoeningBaucke for the useful consultation, and those who agreed to participate in the study.
2
A11 correspondence should be addressed to Daniel J. Cox, Behavioral Medicine Center, Box 223,
University of Virginia Health Sciences Center, Charlottesville, Virginia 22908.
659
OI«6-8693/96/IOOO-0659S09 50/0 C 19% Plenum PoNiihinj Coponlion
660
Cox, Sutpben, Ling, Qufllian, & BorowiU
criteria, the DSM-IV reports that 1% of all 5-year-old children have encopresis.
Sonnenberg and Koch (1989) have observed a steady rise in the frequency of
physician visits for encopresis in children. Encopresis accounts for 25% of all
visits to pediatric gastroenterology clinics (Levine, 1975) and 3% of all visits to
general pediatric clinics (Loening-Baucke, 1993).
Encopresis is hypothesized to result from constipation that produces fecal
impaction. Liquid stool above the impaction gradually develops sufficient pressure to leak around the impaction, thereby producing overflow incontinence.
Routine medical care of encopresis focuses on initial disimpaction of the rectum
with a series of three to six enemas, followed by a prolonged course of laxative
therapy (Loening-Baucke, 1989) to keep the stools soft, frequent, and painless.
This treatment mode has typically resulted in a 5-33% success rate (LoeningBaucke, 1990; Wald, Chandra, Gabel, & Chiponis, 1987).
The reason for this partial response may be due to the fact that standard
laxative therapy does not address potential behavioral mechanisms. For example,
the passage of large and hard impacted stools is frequently painful and frightening. This can encourage encopretic children to ignore early rectal distention cues
(urge to defecate) and/or avoid going to the toilet to have a bowel movement. In
addition to contributing to the constipation, this can set the stage for child-parent
conflict over when to use the toilet.
Davis, Mitchell, and Marks (1976), Lowery, Srour, Whitehead, and Schuster (1985), and others (Wright, 1975) attempted to address these potential behavioral mechanisms. They devised a behavioral toilet training program that encourages detection of and response to rectal distention cues, reinforcing trips to the
toilet and clean pants, and employs scheduled toilet times after meals. In single
group outcome studies, toilet training alone resulted in 60% (Lowery et al.,
1985) to 64% (Davis et al., 1976) success rates. There have been two studies
(Berg, Forsythe, Holt, & Watts, 1982; Nolan, Debelle, Oberklaid, & Coffey,
1991) that have directly compared toilet training to toilet training plus laxative
therapy. Neither study found that the addition of laxative therapy significantly
enhanced the efficacy of toilet training at long-term follow-up. However, Nolan
et al. (1991) did report that the addition of laxative therapy hastened treatment
responsiveness during the initial 6 months of treatment.
The passage of painful stools can trigger reflexive bracing, involving constriction of the external anal sphincter during attempted defecation. This can
lead to a functional obstruction of the anal canal, impairing the passage of stool
and exacerbating defecation pain. Manometric examination has demonstrated
(Meunier, Merechal, & Jaubert de Beaujeu, 1979) that encopretic children paradoxically contract their external anal sphincter when attempting to defecate a
balloon. Neither laxatives nor toilet training directly addresses paradoxical constriction of the external anal sphincter. Consequently, various biofeedback procedures have been additionally employed to train the child how to relax the external
anal sphincter during attempted defecation.
Differential Treatment of Encopresis
661
The first biofeedback reports employed manometric devices that simulated
fecal distention of the rectum through balloon dilatation, while providing children with visual feedback of the mechanical and canal closing. These studies
have reported success rates of 63% (Olness, McParland, & Piper, 1980) to 100%
(Keren, Wagner, Heldenburg, & Golan, 1988). However, there are only two
experimental randomized treatment outcome studies evaluating biofeedback's
efficacy compared to laxative therapy. Wald et al. (1987) reported 67% of their
children responded to biofeedback, compared to 33% who received mineral oil.
Loening-Baucke (1990) found 5% of her children receiving laxative therapy
responded compared to 55% of the biofeedback plus laxative-treated children.
A potentially more convenient and accessible biofeedback procedure involves electromyographic (EMG) biofeedback of the external anal sphincter.
Anal plug EMG biofeedback has been directly compared to balloon manometric
biofeedback (Bleijenberg & Kuipers, 1994) in the treatment of encopretic children. EMG biofeedback was found to be more effective, resulting in a 73%
success rate, compared to a 22% success rate for manometric biofeedback.
Disposable surface EMG electrodes, attached to the anal opening, have also been
used, and found superior to routine medical care (Cox, Sutphen, Dickerson,
Singles, & Whitehead, 1994).
However, no studies have directly compared laxative therapy alone to toilet
training plus laxative therapy. Additionally, no studies have directly compared
toilet training to biofeedback plus toilet training. From a clinical perspective, it is
important to know whether laxative therapy is sufficient, or whether the addition
of biofeedback and/or behavioral techniques makes significant contributions.
Theoretically, it is important to determine whether treatment modalities aimed at
addressing specific hypothetical mechanisms are differentially efficacious.
This study evaluated the relative efficacy of laxatives (LAX) to enhanced
toilet training (ETT) and to anal sphincter biofeedback (BF). This additive treatment approach was taken for two reasons: (a) It goes from least to most complicated, allowing us to determine whether "more is better." (b) It assumes that in
clinical practice therapists routinely use laxative therapy whether they are using
toilet training or biofeedback, and treatment programs employing biofeedback
technologies routinely use toilet training concurrently. Relative efficacy was
evaluated both in terms of traditional across-subject group comparisons, as well
as by assessing the number of children per group that demonstrated significant
improvement in soiling. To assess the theoretical mechanisms for improvement
in soiling, potential mechanisms (e.g., increasing frequency of bowel movement
and self-initiated trips to the toilet, and reducing defecation pain and parental
prompting) were regressed on reduction in soiling.
Since it is assumed that some children only require LAX, or ETT, it is
important to identify factors that predict outcome. Behavioral studies of adults
with agoraphobia, obesity, and sexual dysfunctions have demonstrated that response during early stages of treatment predicts eventual treatment outcome (Cox
662
Cox, Sutphen, Ling, Quillian, & BorowiU
et al., 1988). Similarly, the effects of psychotherapies with children have been
found to be very stable over time (Weisz, Han, Granger, Weiss, & Morton,
1995). Therefore, we evaluated improvement in encopresis during the first 2
weeks of treatment as a predictor of eventual treatment outcome.
Consequently, the hypotheses tested were: (a) Does the addition of toilet
training enhance the efficacy of laxative therapy? (b) Does the addition of biofeedback add to the efficacy of combined laxative therapy and toilet training?
(c) Is the improvement in soiling accounted for by less constipation, less defecation pain, less parentally prompted toileting, or more self-toileting? (d) Does
early response to treatment predict eventual treatment response?
METHOD
Participants
Participants were recruited by physician referral, following direct mailing to
primary care physicians in the University of Virginia catchment area. Inclusion
criteria were child between the ages of 6—15 years, encopresis for at least 1 year,
no documented mental retardation, and no neuromuscular or gastrointestinal
dysfunctions as evidenced by history and physical examination. All participants
were physician-referred and all had previously failed various types of therapy.
Table I displays demographics for all 44 participants, and for the three treatment
groups. There were no differences between these groups. Table II lists baseline
bowel behaviors.
Procedure
Baseline assessment involved 14 days of recording toilet behavior by a
computerized voice mail system. When the computer called the child's home
Table I. Means of Overall and Group-Specific Subject Characteristics
Age \M(SD)]
Gender (M/F)
Duration of symptoms (months)
[M(SD)\
Single-parent families (n)
Family income (thousand $)
IM(SD))
All
LAX
ETT
BF
9.0 (2.0)
34/10
65 (39)
8.8 (2.3)
10/6
51 (36)
9.0(1.6)
12/2
76(46)
9.1 (1.9)
12/2
70 (32)
2
33(16)
0
37(15)
1
26 (16)
1
35 (15)
"LAX = laxative therapy, ETT = enhanced toilet training, BF = anal sphincter biofeedback.
Differential Treatment of Encopresis
663
each evening, a parent identified himself or herself by entering their social
security number and then answered questions by pressing their telephone's number pad. Parents reported the number of their child's self-initiated and parentinitiated trips to the toilet, number of voluntary bowel movements in the toilet,
pain with defecation, number of soilings, number of teaspoons of laxatives, and
number of enemas or suppositories used, during the previous 24 hours. Parents
rated defecation pain based on either observation or inquiry, depending on child's
age and availability. Pain was rated on a 5-point Likert scale: no pain to extreme
pain. The major advantages to this voice mail data collection system were that no
more than 24 hours elapsed between relevant events and data recording, data
were directly added to an ASCII file and were immediately analyzed for tabulation and graphing. This voice mail system yielded robust split-half reliability,
with correlations ranging from .86 to .97 (ps < .001), and differentiated symptomatic from nonsymptomatic siblings (p < .0002) (Ling, Borowitz, Sutphen,
Marshall, & Cox, 19%).
Participants then came to the Behavioral Medicine Center and completed a
series of psychological tests, and underwent physical and manometric exams.
The children drew from a hat for block randomization for group assignment,
where 2 of every 6 successive children were randomized to one of the three
treatments. On the same day of, and immediately following the physical exam,
the children had their first treatment session. To assess cost-effectiveness, number of treatment sessions was open-ended and were scheduled every 1 to 2 weeks
on an "as needed" basis.
During the initial 2 weeks of treatment, and 3 months after the initiation of
treatment, parents repeated the 14-day voice mail symptom diary.
Laxative Therapy. LAX involved an initial series of Fleet's phosphate enemas. Parents were instructed to administer enemas at home at 12-hour intervals
for 3 to 4 days to remove impacted stool. This occurred immediately before the
physical exam. Following disimpaction, children were treated with Milk of
Magnesia and/or Senna syrup at a frequency and volume sufficient to produce at
least one soft bowel movement per day. If the stools were liquid, the laxative
dose was reduced. If the child went for more than 2 days without a bowel
movement, either an enema or a rectal suppository was administered, and the
laxative dosage was increased. This therapy was continued for 5 months. During
month 6, parents were instructed to taper off laxative use and introduce more
fluids and foods containing fiber. No specific dietary instructions were given
beyond increasing fiber and fluid intake.
Enhanced Toilet Training. Children in the ETT group received similar enema and laxative therapy, with a clinical psychologist (D.J.C., W.L.) adjusting
the laxative dose. The only difference to LAX was that laxatives were reduced
gradually once the child demonstrated a stable bowel movement frequency with
no soiling episodes. Parents and child were instructed on the psychophysiology
664
Coi, Sutphen, Ling, Quillian, & Horowitz
of constipation/encopresis, and how responding to early rectal distention cues
and regular toileting was critical to avoid reimpaction and establish regular bowel
habits. Various incentive programs were established, depending on the developmental age and the motivation of the child. Target behaviors were spontaneous
trips to the toilet and clean pants. Our toilet training was "enhanced" because
instructions were given on the role of paradoxical constriction of the external
anal sphincter and because appropriate defecation straining was modeled. The
therapist sat on a portable toilet, demonstrating how to relax legs and feet, how to
take in a deep breath and hold it while sitting up straight, and how to push down
with the held breath and push in with the rectus abdominous muscle in order to
propel a stool out. The child then replicated this while sitting on a portable toilet.
Parents were instructed to prompt this behavior at home. Additionally, "toilet
time" was scheduled daily, when the child would sit on the toilet for 12 minutes,
beginning 15 to 30 minutes after the same two meals. During these times,
children were instructed to practice tensing and relaxing their external and sphincter for the first 4 minutes, with the objective to localize control of and fatigue
the sphincter, as well as mechanically stimulate the rectum. To desensitize the
child to toilet sitting, the second 4 minutes were spent "having fun" while being
read to or playing games. During the final 4 minutes the child was to strain and
attempt to have a bowel movement. This routine toilet sitting was discontinued
2 weeks following the last scheduled treatment session.
Biofeedback. Children receiving BF had the same LAX and ETT instructions, and simultaneously received biofeedback training. Surface EMG biofeedback was employed because it is generally more available, less invasive, and less
expensive than manometric procedures (Cox et al., 1994). After receiving the
general educational overview, children undressed up to their waist, put on a
gown, and laid on their stomach on an examining table. One silver/silver chloride electrode (Tender-Trace Neonatal #01-7130D, NDM, Dayton, OH) was
attached to the coccyx and two bilaterally to the anal opening. Underpants were
then replaced and the child sat on a portable toilet. The J&J 1-330 system was
used and its standard "Egg Drop" game was initially employed. This required the
child to learn to tighten and relax his/her external anal sphincter in order to
control a "basket" that moved horizontally across the bottom of the screen,
depending on muscle contraction, to catch the "falling egg." Typically, initial
control was spastic and paradoxical (tightening when intending to relax). After
15 to 20 minutes, children typically learned to control their external anal sphincter. The criteria for successful control was "catching" 25 eggs in 10 minutes,
which was achieved by all biofeedback participants by the end of the first
session. The video display was then changed to a circle that constricted when the
sphincter tightened and opened when the muscle relaxed. While viewing this
biofeedback display, children were then asked to strain while keeping their anal
canal (circle) open. Typically, children were able to achieve this within 5 to 10
minutes. Consequently, BF differed from ETT in its direct exercising of the
Differential Treatment of Encopresis
665
external anal sphincter and viewing its action on a computer screen during these
exercises.
All Treatments. Child and parents were given specific written instructions
concerning the mechanisms of bowel movements and "homework" assignments,
such as when and how much laxative to consume, and when to sit on the
toilet.(Written instructions are available upon request from Daniel J. Cox.) The
voice mail computer printout from the first 2 weeks of treatment was made
available to the clinicians for the next patient contact. The mean (standard deviation) number of treatment sessions per child for LAX, ETT, and BF groups were
4.1 (1.9), 3.0 (1.2), and 3.4 (1.4), respectively, F(2, 41) = 0.57, p = .57,
indicating that the addition of treatments components did not increase the number
Table II. Means of Dependent Variables per Day Across Groups at Baseline, Two Weeks,
and Three Months After Treatment Initiation
Self-toileting
LAX
ETT
BF
Prompted toileting
LAX
ETT
BF
Bowel movements in toilet
LAX
ETT
BF
Pain rating of bowel movements
LAX
ETT
BF
Soiling/day
LAX
ETT
BF
Teaspoons of laxatives/day
LAX
ETT
BF
Enemas/week
LAX
ETT
BF
8-ounce glasses fluids/day
LAX
ETT
BF
Baseline
2 weeks
3 months
M
SD
M
M
1.1
1.3
1.1
0.5
1.1
0.7
1.6
1.5
1.7
0.8
0.9
0.7
1.7
1.4
1.4
0.7
0.9
0.6
0.5
1.2
1.2
0.7
1.0
1.3
0.6
1.0
0.9
0.9
0.4
0.7
0.5
0.7
0.7
0.7
0.6
0.5
1.0
0.6
0.8
0.6
0.6
1.0
1.7
1.3
1.5
0.7
0.5
0.7
1.5
1.1
1.2
0.5
0.4
0.7
0.4
0.3
0.3
0.5
0.5
0.5
0.2
0.2
0.2
0.3
0.3
0.3
0.1
0.1
0.2
0.1
0.1
0.4
1.2
1.3
1.3
0.7
1.0
0.9
0.7
0.3
0.3
0.6
0.3
0.3
0.7
0.2
0.3
0.8
0.2
0.4
1.0
3.1
2.9
1.6
6.5
4.8
4.8
4.0
63
2.2
3.5
2.8
4.7
1.1
3.1
5.0
1.8
2.8
0.05
0.05
0.04
0.1
0.1
0.1
0.04
0.03
0.06
0.08
0.05
0.09
0.02
0.04
0.08
0.05
0.08
0.1
4.1
4.5
4.7
0.9
2.1
1.2
4.5
4.8
5.0
0.8
2.2
1.3
4.5
5.4
5.4
1.2
1.6
1.8
SD
SD
666
Cox, Sntpben, Ling, QuUlian, & Borowitz
of treatment sessions. Additionally, as illustrated in Table II, all three groups
complied with the laxative regimen, similarly increasing their laxative dose
during the first 2 weeks of treatment.
RESULTS
Relative Treatment Efficacy. The primary dependent variable was number of
soilings per day for the 14 days before and 3 months following initiation of
therapy, as defined by voice mail data. While random assignment did result in
equivalent frequency of all dependent variables (all ps > .05), there were nonsignificant mean differences with large standard deviations (see Table II). Consequently, percentage change was calculated for each variable for each child.
Percentage change was compared across groups using a one-way ANOVA, with
a Bonferroni correction of p < .01. ANOVA indicated that there was a significant between-group difference for reduction in soiling from baseline to three
months, F(2, 41) = 7.99, p = .001, with contrasts indicating that ETT, t(4l) =
3.70, p < .001, and BF, /(41) = 3.08, p = .004, were superior to LAX, and
equivalent to one another, <(41) = 0.67, p = .50. There were no other group
differences in terms of the dependent variables appearing in Table II.
Impact on Individual Children. Individual /-tests were performed on each
child's 14 days of baseline and 3-month data to determine which children were
significantly benefited by the various treatments. Because there were multiple ttests, a Bonferroni correction was applied that required a significance level of/?
< .002. Analysis of individual children's data paralleled group findings. T-test
comparisons of number of soilings during the 14 days at baseline to 3 months
were performed, patient by patient. This indicated that 19, 71, and 64%, respectively, of LAX, ETT, and BF children significantly (p < .002) reduced their
soiling. The Kruskal-Wallis test indicated this distribution was significantly different in the three groups, \H2) = 11.42, p = .003. LAX differed from ETT (p
= .001) and BF (p = .03), while ETT and BF did not differ from one another.
For those children who experienced significant improvement, this represented a
mean reduction of soiling from 1.4 per day to 0.2 per day, with percentage
reduction in soiling ranging from 50 to 100%. In LAX, ETT, and BF, 1, 2, and 2
children were marginally improved (ps = .01 to .002). These marginally successful children had a mean reduction from baseline to 3 month in soiling from
1.1 per day to 0.3 per day.
Predicting Treatment Outcome. When collapsing across groups, reduction
in soiling from baseline through the first 2 weeks of treatment correlated with
improvement from baseline to 3 months (r = .92, p < .001, r 2 = 85%). Overall
group reduction in soiling was 81% and 81% by 2 weeks and 3 months, respectively. Failure to respond in the first 2 weeks predicted eventual treatment nonre-
Differential Treatment of Encopresis
667
sponders. This was very sensitive. Of the 13 children who demonstrated <40%
reduction in soiling at 2 weeks, all were eventually classified treatment failures.
However, it was not extremely specific. Of all treatment failures, 40% demonstrated an initial reduction in soiling of >40% during the first 2 weeks of
treatment. All children who eventually achieved >60% improvement had demonstrated >50% reduction in soiling during the initial 2 weeks of treatment, and
only 2 children who had achieved >50% improvement at 2 weeks were eventual
treatment failures.
Mechanisms of Therapeutic Improvement. Since change in children's soiling frequency from baseline to the first 2 weeks of treatment accounted for 85%
of the eventual treatment benefits, assessment of treatment mechanisms involved
predicting reduction of soiling during the first 2 weeks of treatment with regression analyses, using as predictors percentage change in bowel movements frequency, defecation pain, and both self- and parental-prompted toileting. When
collapsing across groups, regression analyses indicated that improvement in
soiling was significantly related to increase in bowel movements (p < .0001, r2
= 37%), reduction in parental-prompted toileting (p < .002, r2 = 9%), reduction of defecation pain (p = .02, r2 = 5%), and reduction in self-toileting (p =
.03, r2 = 5%). Post hoc analyses revealed that the relationship between selftoileting and improvement in soiling was curvilinear, where too little self-toileting was associated with both increased soiling and fewer bowel movements,
while high frequency self-toileting was associated with more soiling. An optimal
range of self-toileting appeared to be between 1.5 and 2.5 per day.
DISCUSSION
When considering either group mean change or number of individual children who significantly benefited from treatment, the current study demonstrates
encopresis is significantly more improved by ETT and BF, relative to LAX
alone. Even though encopretic children have been shown to suffer from paradoxical constriction of their external anal sphincter, the addition of EMG biofeedback to directly address this mechanism did not enhance group treatment outcome. This may be due to a ceiling effect, where only 2 (14%) of the ETT
children were clearly classified as treatment failures. It should also be pointed
out that our ETT group included all aspects of BF, except electrode placement
and visual feedback. Therefore, while direct visual feedback of the external anal
sphincter may not be critical in general, addressing paradoxical constriction and
appropriate straining may be important.
It may not be surprising that most LAX children did not respond, since all
children had previously been tried on laxative therapy, initiated either by parents
or primary care physicians. However, our LAX was relatively intensive. These
668
Cox, Sutpben, Ling, Quillian, & Borowiti
children were followed daily by the voice mail symptom diaries and were seen an
average of 4.1 times by pediatric gastroenterologists (J.S. and S.B.)- However,
this is consistent with the idea that initial treatment failure predicts eventual
treatment failure.
Overall, reduction in encopresis was associated with increasing bowel
movements, and reducing both defecation pain and reliance on parental prompting to use the toilet. The most important of these was increasing the frequency of
bowel movements. This is consistent with the assumption that encopresis is a
function of constipation, resulting in overflow incontinence.
However, while t i l and BF reduced encopresis more than LAX, they
achieved this without differentially improving bowel movement frequency, painful defecation, toilet avoidance, or parental reliance. The question to be asked is,
why are the behaviorally based treatments more effective? Analysis of number of
treatment sessions indicated that LAX, ETT, and BF children were seen an
equivalent number of sessions (4.1, 3.0, and 3.4 visits, respectively). Additionally, the differential efficacy cannot be explained by a nonspecific variable,
since the differential treatment efficacy was specific to soiling and not to the
other dependent variables, such as bowel movement frequency. It may be that the
anal sphincter exercises common to both ETT and BF were beneficial training
children in fecal retention.
Initial treatment failure predicted eventual treatment failure, regardless of
treatment group. This is consistent with behavioral treatment of agoraphobia,
sexual dysfunction, weight loss, and hypercholesteremia, as well as responsiveness to psychoanalytic psychotherapy (see Cox et al., 1988, for summary). From
a clinical perspective, this suggests that children with encopresis who do not
respond after 2 weeks of treatment should be tried on an alternative strategy. It is
not clear from the present data whether these early treatment nonresponders
would have benefited from a different approach or whether these children would
have been treatment failures regardless of the intervention. The latter speculation
is unlikely, however, given that there were significantly fewer responders in the
LAX group. Additionally, subsequent treatment of the LAX nonresponders with
BF was generally successful.
Contrary to our speculations, at baseline these children with encopresis did
not report excessive defecation pain nor avoidance of the toilet. On a 0 (none) to
4 (extreme) Likert pain rating these children gave a mean rating of approximately
0.4 (SD = 0.5). While it is possible that this low pain rating is a reflection of the
insensitivity of our measure, this is unlikely for two reasons. First, this prospective minimal pain report paralleled parents' retrospective reports on our screening
questionnaire. Second, there was minimal avoidance behavior reported, with an
average of one or more voluntary trips to the toilet daily. However, a near
universal phenomenon was the report of pain with defecation and subsequent
avoidance of the toilet at some time in the past. It may be that pain functions in
Differential Treatment of Encopresis
669
more of an anticipatory nature, and the avoidance is more subtle, in terms of
more muscular bracing (paradoxical constriction) and less vigorous straining and
less time spent on the toilet per visit.
Although this study does not demonstrate that anal sphincter biofeedback
significantly added to ETT, the present design does not quantify the specific
benefits of biofeedback. It may be that ETT is not necessary at all, and that all is
required is anal sphincter biofeedback. This study does not address the relevance
of diet. Although reduced fiber has frequently been implicated in constipation,
this has not been scientifically verified. In part, the absence of such confirmatory
data is due to the difficulty documenting food intake of children between the ages
of 6 and 15 years, who have various food sources outside the control and
awareness of parents. Though it is important to know that early response to
treatment predicts eventual treatment outcome, it is essential that we document
what accounts for early treatment failure. Future research addressing such limiting factors will help in the development of even more effective treatments.
Given these limitations, the implications these data have for pediatric psychology are that ETT, including instructions in appropriate straining and aggressive laxative therapy, should be the treatment of choice for pediatric encopresis.
If the child does not demonstrate a significant reduction in soiling (>50%) by the
end of the second week of treatment, then an alternative therapy should be
pursued. Alternative approaches may involve anal sphincter biofeedback, family
therapy, or more extensive psychological and medical evaluations.
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