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The Standardization of Terminology of
Lower Urinary Tract Function in Children
and Adolescents: Report from the Standardisation
Committee of the International Children’s Continence Society
Tryggve Nevéus,* Alexander von Gontard, Piet Hoebeke, Kelm Hjälmås,†
Stuart Bauer, Wendy Bower, Troels Munch Jørgensen, Søren Rittig, Johan Vande Walle,
Chung-Kwong Yeung and Jens Christian Djurhuus
From the Section for Pediatric Nephrology, Uppsala University Children’s Hospital (TN), Uppsala, Sweden, Institution for Child and
Adolescent Psychiatry, University of Saarland (AvG), Homburg, Germany, Departments of Pediatric Urology and Urogenital
Reconstruction (PH) and Pediatric Nephrology (JVdW), Ghent University Hospital, Ghent, Belgium, Department of Urology, Children’s
Hospital and Harvard Medical School (SB), Boston, Massachusetts, Division of Pediatric Surgery, Chinese University of Hong Kong,
Prince of Wales Hospital (WB, CKY), Hong Kong Special Administrative Region, People’s Republic of China, and Departments of Pediatric
Urology (TMJ, JCD) and Pediatrics (Nephrology Section) (SR), Skejby University Hospital, Aarhus, Denmark
Purpose: We updated the terminology in the field of pediatric lower urinary tract function.
Materials and Methods: Discussions were held of the board of the International Children’s Continence Society and an
extensive reviewing process was done involving all members of the International Children’s Continence Society as well as
other experts in the field.
Results and Conclusions: New definitions and a standardized terminology are provided, taking into account changes in the
adult sphere and new research results.
PREFACE
Background
Lower urinary tract function and malfunction in chil-
dren is a field rife with semantic confusion. Different
groups use different definitions of commonly used
terms, such as enuresis, incontinence, OAB, treatment
response, etc. Sometimes names applied to specific condi-
tions are used interchangeably to denote general dysfunc-
tion and vice versa. This confusion partly reflects modern
research, which has radically changed our views of these
conditions during the last decades, and partly the fact that
children are growing individuals who differ from adults.
Many definitions that are adequate in adults are irrelevant
in childhood and vice versa. Thus, symptoms such as bed-
wetting and findings such as incomplete voiding may be
normal in the toddler and pathological in the school-age
child. Maturation of the central nervous system is an impor-
tant factor to consider when talking about incontinence in
children but it has no basis in adult disease, whereas central
nervous system alterations in the aging population are not
relevant in childhood.
The ICCS, which is the global multidisciplinary organi-
zation for professionals involved with the pediatric LUT, has
previously published guidelines to lessen this confusion
1
but
recent advances in enuresis and incontinence research re-
quire clarification and modification of the terminology. This
task is being fulfilled by the ICCS board.
We recognize and acknowledge the valuable contribu-
tions made by our late friend Dr. Kelm Hjälmås, who par-
ticipated in the preliminary preparation of this document,
and by the ICS, which created guidelines for LUT terminol-
ogy in adults.
2
We are also grateful for constructive criticism
provided by other experts (Appendix 1).
Scope and Use of the Document
The aim of this document is to provide firm, unequivocal
guidelines for the terminology of LUT function and malfunc-
tion in childhood. Although it is hopefully useful for the
clinician, its main use will be in the research setting, where
adherence to 1 terminology (ie this terminology) will make it
easier to compare studies and decrease confusion among
researchers. At future ICCS conferences submitted material
will be required to use this terminology and we propose that
groups publishing in this research field should include in
their text the phrase, “Definitions conform to the standards
recommended by the International Children’s Continence
Society except where specifically noted,” or words to that
effect.
Note that the current document in no way tells research-
ers or clinicians what to do, only which words to use. Rec-
ommendations regarding good investigational practice and
treatment are not within the scope of this article. It is the
intent of the ICCS in the near future to develop guidelines in
those fields aimed at specific abnormalities.
In this text symptoms are followed by investigational
tools, signs, conditions and treatment parameters. Through-
out the text the relevance of the entities in various age
* Correspondence: Uppsala University Children’s Hospital, S-751
85 Uppsala, Sweden (telephone: ⫹46 18 6110000; FAX: ⫹46 18
6115853; e-mail: tryggve.neveus@kbh.uu.se).
† Former address: Department of Pediatric Urology, Queen Sil-
via’s Hospital for Children, Gothenburg, Sweden.
0022-5347/06/1761-0314/0 Vol. 176, 314-324, July 2006
THE JOURNAL OF UROLOGY
®
Printed in U.S.A.
Copyright © 2006 by AMERICAN UROLOGICAL ASSOCIATION DOI:10.1016/S0022-5347(06)00305-3
314
groups is stated. Appendix 2 lists the terminology for ano-
rectal function since anorectal and LUT functions are inter-
related. One can scarcely speak about one without mention-
ing the other. However, we recognize that the ICCS does not
have the authority to prescribe changes in anorectal/gastro-
intestinal terminology and, thus, only existing definitions
and terminology are quoted in Appendix 2. Appendix 3 pro-
vides a short alphabetical list of the most commonly used
entities defined in this document.
Underlying Principles
Certain general principles were continuously applied during
the creation of this terminology. 1) The terms should be
descriptive and not express theories or suppositions, however
well grounded they may be, regarding underlying pathogene-
sis. 2) Terminology should be unambiguous. 3) Words should
be neutral and free of judgments. 4) Words that have been
used for many years have become the vernacular and cannot
be discarded without compelling reasons. 5) When possible
and reasonable, pediatric terminology should follow the ter-
minology for adults, as established by the ICS.
2
6) Defini-
tions must make it possible to assign the correct descriptive
term to the child without invasive or complicated investiga-
tions. A good case history and a bladder diary should usually
suffice. 7) The focus on the child as a growing, maturing
individual should always be kept in mind. 8) The division of
patients into subgroups, such as OAB or voiding postpone-
ment, is less important than the measurement and declara-
tion of relevant variables, such as daytime voiding fre-
quency. The subgrouping process makes sharp boundaries
out of biological continua and the choice of subgrouping
criteria makes us biased. Furthermore, these criteria may
prove irrelevant in the future.
SYMPTOMS
Symptoms are classified according to their relation to the
voiding and/or storage phase of bladder function. Symptom
duration is irrelevant to the use of these terms. Incontinence
is called incontinence even if it occurs just once.
Storage Symptoms
Increased or decreased voiding frequency. Estimates of
voiding frequency are relevant from age 5 years and there-
after or from the attainment of bladder control. The obser-
vation that the child consistently voids 8 or more times daily
denotes increased daytime frequency, whereas 3 or fewer
voidings daily are called decreased daytime frequency. The
rationale behind this choice of limits is 1) the observation
that the number of voidings in continent children is between
3 and 5, and 7 times daily,
3,4
and 2) the common experience
that children with incontinence or other bladder complaints
who void just 3 or 4 times daily are helped by going to the
toilet more often. Note that in this article the word daytime
is consistently used instead of diurnal. The latter term is
ambiguous, in that it is sometimes used to denote all 24
hours of the day and night, and sometimes just the daytime
hours.
Caregivers may be unable to report voiding frequency
until they have had a chance to observe the child at home
and complete a bladder diary, which is an important adjunc-
tive measure to objectively assess this and other parame-
ters. The relevance of these observations increases when
interpreted in conjunction with fluid intake.
Incontinence. Incontinence (urinary incontinence) means
uncontrollable leakage of urine. It can be continuous or
intermittent.
Continuous incontinence means constant urine leakage,
a phenomenon that is almost exclusively associated with
congenital malformations, ie ectopic ureter, or iatrogenic
damage to the external urethral sphincter. This term, which
replaces the term total incontinence, is applicable to chil-
dren of all ages since even infants normally have a degree of
cortical control over bladder emptying and they are dry
between voidings.
5
Intermittent incontinence is urine leak-
age in discrete amounts. It can occur during the day and/or
at night, and it is applicable to children who are at least 5
years old. Enuresis means intermittent incontinence while
sleeping. Note that in contrast with previous terminology,
the terms (intermittent) nocturnal incontinence and enure-
sis are now synonymous. Thus, any type of wetting episode
that occurs in discrete amounts during sleep is called enure-
sis. Furthermore, the symptom of bedwetting is called en-
uresis or (intermittent) nocturnal incontinence regardless of
the presence or absence of concomitant daytime symptoms.
Enuresis may be called nocturnal enuresis to add extra
clarity but the ambiguous term diurnal enuresis is obsolete
and should be avoided. Daytime incontinence is, of course,
incontinence during the day. Children with combined day-
time and nighttime wetting have dual diagnoses, namely
daytime incontinence and nocturnal incontinence or enure-
sis. If the word diurnal is used instead of daytime, it should
be made clear that only the waking portion of the 24 hours
is denoted. For subdivisions of enuresis and daytime incon-
tinence the reader is referred to the section on LUT condi-
tions. The figure shows the terminology graphically.
Urgency. Urgency means the sudden and unexpected expe-
rience of an immediate need to void. The term is not appli-
cable before the attainment of bladder control or age 5 years,
whichever occurs first. Other symptoms of bladder sensation
(sensation of bladder filling, etc) cannot reliably be elicited
from the history and they are relevant in the cystometric
setting only (see below).
Nocturia. Nocturia means that the child must awaken at
night to void. The definition is relevant from the age of 5
Subdivision of urinary incontinence in children
TERMINOLOGY FOR LOWER URINARY TRACT FUNCTION IN CHILDREN 315
years. Nocturia is common among school children
6
and it is
not necessarily indicative of LUT malfunction. Note that the
term nocturia does not apply to children who awaken for
reasons other than a need to void, for instance children who
awaken after an enuretic episode.
Voiding symptoms. The absence of voiding symptoms re-
ported by a child does not mean that there are no such
symptoms. They may not reliably have been observed by a
caregiver or reported by a child until about age 7 years.
Pain during voiding is considered under other symptoms
later in this document. The terms splitting or spraying, as
used in adult terminology,
2
refer to the appearance of the
urine stream and they are of little relevance in childhood,
except in instances of meatal stenosis in circumcised boys.
Hesitancy. Hesitancy denotes difficulty in the initiation of
voiding or that the child must wait a considerable period
before voiding starts. The term is relevant from the attain-
ment of bladder control or age 5 years.
Straining. Straining means that the child applies abdom-
inal pressure to initiate and maintain voiding. If observed,
straining is relevant in all age groups.
Weak stream. This term is used for the observed ejection of
urine with a weak force and it is relevant from infancy and
thereafter.
Intermittency. Intermittency is the term applied when
micturition occurs not in a continuous stream, but rather in
several discrete spurts. This may be described in all age
groups but it is regarded as physiological up to age 3 years
if not accompanied by straining.
Other Symptoms
Holding maneuvers. These are observable strategies used
to postpone voiding or suppress urgency. The child may or
may not be fully aware of the purpose of the maneuvers but
it is usually obvious to caregivers. Common maneuvers are
standing on tiptoe, forcefully crossing the legs or squatting
with the heel pressed into the perineum.
7
The term is rele-
vant from the attainment of bladder control or age 5 years.
Feeling of incomplete emptying. This term is self-explan-
atory. It is not relevant before adolescence since younger
children usually do not recognize and describe this
symptom.
Post-Micturition dribble. This term is used when the
child describes involuntary urine leakage immediately after
voiding has finished. It is applicable after the attainment of
bladder control or age 5 years. Vaginal reflux (see below)
may produce this symptom.
Genital and LUT pain. Most kinds of genital and LUT
pain that occur in adults may theoretically occur in child-
hood. However, in practice pediatric pain in this area is
usually nonspecific and difficult to localize. Thus, it is not
defined more specifically here.
TOOLS OF INVESTIGATION
The first and foremost tools for assessment of the LUT in
childhood, namely history taking, observation and physical
examination, need not be more closely defined here since
they are central to the craft of the physician regardless of
which organ system is in focus. However, bladder diaries,
voiding observations and urodynamic techniques require the
specific terminology defined in this section. Appendix 4 lists
these techniques. Questionnaires are also used, especially in
the fields of child psychiatry and psychology.
For descriptions of urodynamic observations in children
the ICS standardization is strictly followed.
8
Only the para-
graphs that are relevant in children are included in this
report.
The Bladder Diary
The recording of voiding and bladder related symptoms at
home under normal conditions is crucial for the assessment
of LUT function in childhood and it is relevant after attain-
ment of bladder control or age 5 years. Various protocols
kept for a variable number of days have been used for this
purpose. Also, many names have been given to these proto-
cols. In accordance with ICS guidelines we propose that a full
diagnostic protocol in the research setting should be called a
bladder diary and include certain data (Appendix 5).
9 –11
Ex-
tractable information is further defined in the symptoms
and signs sections of this article. Less exhaustive protocols,
such as those commonly used during treatment and fol-
lowup, should be labeled frequency-volume charts.
Pad testing refers to the assessment of urine losses due to
daytime incontinence by repeat measurement of the weight
of absorptive pads placed in the underwear. The term is
applicable to incontinent children from age 5 years. It can be
included in the bladder diary but is seldom used in the
pediatric setting. More relevant is the assessment of enure-
sis urine volume by the measurement of diaper weight.
Urine Flow Measurements
Measurement of urine flow and residual urine (with ultra-
sound) as a stand alone examination is by far the most
common procedure in pediatric urodynamic practice. To a
large degree the results of the flow/residual examination
decide whether the child requires an invasive urodynamic
investigation.
Flow/residual urine measurement in a child should be
repeated again at the same setting in a well hydrated child
to ensure that a reasonable volume of urine is expelled with
each micturition. Even if it is time consuming, this increases
accuracy exponentially. If these first 2 measurements are
dissimilar, a third measurement may be needed. Flow mea-
surement is a cornerstone of diagnosis in children after toilet
training. If available, the addition of pelvic floor EMG re-
cordings increases the value of uroflow measurements.
Flow rate. Maximum flow rate is the most relevant vari-
able when assessing bladder outflow. Sharp peaks in the
flow curve are usually artifacts, and so maximum flow
should be documented only at a peak level with a duration of
at least 2 seconds.
12
In studies of normal children and adults
a linear correlation has been found between maximum flow
and the square root of voided volume.
13
Thus, preliminary
evaluation of the results of a flow measurement is possible.
If the square of the maximum flow ([ml per second]
2
) is equal
to or exceeds voided volume in ml, the recorded maximum
flow is most probably within the normal range.
TERMINOLOGY FOR LOWER URINARY TRACT FUNCTION IN CHILDREN316
Flow curve shape. The precise shape of the flow curve is
determined by detrusor contractility, any abdominal strain-
ing and the bladder outlet. In normal voiding the curve is
smooth and bell-shaped. OAB may produce an explosive
voiding contraction that appears in the flow measurement as
a high amplitude curve of short duration, ie a tower-shaped
curve. A child with organic outlet tract obstruction often has
a low amplitude and rather even flow curve, that is a pla-
teau-shaped curve. Similarly this may be the case when
there is a tonic sphincter contraction during voiding. How-
ever, more commonly sphincter overactivity during voiding
is seen as sharp peaks and troughs in the flow curve, that is
as an irregular or staccato flow curve. This is labeled as a
continuous but fluctuating flow curve. To qualify for the
staccato label the fluctuations should be larger than the
square root of the maximum flow rate. Finally, in case of an
underactive or acontractile detrusor when contraction of the
abdominal muscles creates the main force for bladder evac-
uation, the flow curve usually shows discrete peaks corre-
sponding to each strain, separated by segments with zero
flow, namely an interrupted or fractionated flow curve. To
avoid confusion due to a multitude of terms regarding the
shape of the flow curve the ICCS suggests that a certain
terminology should be adopted, including bell, tower, pla-
teau, staccato and interrupted. These appellations are not a
guarantee to the underlying diagnostic abnormality, but
rather they should serve as a guide to the existence of a
specific condition.
Post-void residual urine. Today residual urine is as-
sessed by ultrasonography after a uroflow measurement. In
the diagnostic setting real-time ultrasound equipment is
preferred. The lowest acceptable limit of 10% of bladder
capacity, as often stated in adults, is not relevant in infants
and children. Studies in healthy infants and toddlers have
shown that they do not empty the bladder completely every
time but they do so at least once during a 4-hour observation
period.
14
However, older children should be expected to ha-
bitually empty the bladder completely. The unavoidable de-
lay of a few minutes after finishing voiding until ultrasonog-
raphy results in bladder refilling with up to 5 ml, which is
the upper value of residual urine not associated with urinary
tract infection. A range of 5 to 20 ml may be associated with
insufficient emptying, so that the examination should be
repeated. More than 20 ml residual urine found on repetitive
occasions indicates abnormal or incomplete emptying, pro-
vided that 1) there has not been any time delay exceeding 5
minutes from the end of voiding until ultrasonography is
performed and 2) the child has not over ambitiously delayed
micturition and, thus, achieved a state of bladder fullness in
excess of what is normal for him or her. The case of a longer
time delay can be compensated for by subtracting 1 or 2 ml
from measured residual urine for every minute beyond 5.
Invasive Urodynamic Investigations: Cystometry
Urodynamic (cystometric) techniques. Urodynamic
studies investigate the filling and emptying phases of blad-
der function. Note that in the pediatric setting specific ad-
aptations regarding staff training, environment, parental
support, etc must be made to make the whole examination
child friendly. If the suprapubic route is used, a minimal
delay of 5 to 6 hours is needed between catheter insertion
and urodynamic recording. If a transurethral catheter is
used, it must be of as small a diameter as possible since a
large catheter can cause outflow obstruction, especially in
small boys.
The word cystometry is commonly used to describe uro-
dynamic investigation during the filling phase of the mic-
turition cycle. The filling phase starts when filling com-
mences and ends when the patient and urodynamicist
decide that permission to void has been given. Such preci-
sion may not be feasible in pediatric practice because all
infants and many children void without permission. Thus,
the distinction between the filling and voiding phases can
only be made later, when the curve is analyzed
In accordance with the ICS definitions the physiological
filling rate is defined as a filling rate less than the predicted
maximum rate of urine production by the kidneys, ie body
weight in kg divided by 4 and expressed in ml per minute.
2
A nonphysiological filling rate is defined as a filling rate
greater than this predicted maximum. In children only phys-
iological filling rates should be used. It must be mentioned
that this wording is suboptimal since urine production of
3,600 ml during 24 hours in a 10 kg child is clearly not
physiological in the true sense of the word. However, the
physiological filling rate represents an acceptable filling rate
during standard urodynamic investigations. Hjälmås pro-
posed using a filling rate of 5% of expected bladder capacity,
expressed in ml per minute.
15
The use of natural fill (ambulatory) cystometry provides a
true physiological filling rate and offers a more accurate
representation of bladder activity than traditional cystom-
etry. This is the technique of choice in pediatric urodynamics
if time and equipment are available. If this is not feasible or
practical, filling rates of 5% to 10% of known or predicted
capacity may be used.
Bladder storage function should be described in terms of
bladder sensation, detrusor activity, bladder compliance and
bladder capacity.
Bladder sensation during filling cystometry. The ICS
definitions of bladder sensation are only applicable to older
children and adolescents. Infants and young children are
unable of indicating these different bladder sensations. A
strong desire to void is probably the only sensation that
some children can express.
During filling cystometry reduced bladder sensation is
defined as decreased sensation throughout bladder filling
and absent bladder sensation is defined as no bladder sen-
sation. The 2 conditions can be observed in children with an
underactive detrusor, formerly called lazy bladder. When-
ever filling exceeds expected bladder capacity for age (see
below under signs) and no sensation is reported, we can
invoke the term reduced bladder sensation.
Nonspecific bladder sensations are sometimes observed
in children. Holding maneuvers (see above) may be evi-
denced by toe curling and leg movements even in infants.
When bladder filling creates pain in children, filling should
be stopped.
Detrusor function during filling cystometry. Normal
detrusor function allows bladder filling with little or no
change in pressure and without involuntary phasic contrac-
tions despite provocation. Thus, in infants and children any
detrusor activity observed before voiding is considered
pathological.
TERMINOLOGY FOR LOWER URINARY TRACT FUNCTION IN CHILDREN 317
Detrusor overactivity, not to be confused with OAB, is a
urodynamic observation characterized by involuntary detru-
sor contractions that are spontaneous or provoked during
the filling phase, involving a detrusor pressure increase of
greater than 15 cm H
2
O above baseline. In an adult with
normal sensation urgency is likely to be experienced in con-
junction with such detrusor contractions. In children report-
ing the sensation of urgency is less reliable. Detrusor over-
activity may also be qualified, when possible, according to
cause into neurogenic detrusor overactivity when there is a
relevant neurological condition (this term replaces the term
detrusor hyperreflexia) or idiopathic detrusor overactivity
when there is no defined cause. The term detrusor overac-
tivity replaces the previous term detrusor instability.
Bladder capacity and compliance during filling cys-
tometry. In infants and children the difference between
cystometric capacity and maximum cystometric capacity is
less relevant, given the difficulties in children in reporting
bladder sensation adequately.
Bladder compliance describes the relationship between
the change in bladder volume and change in detrusor pres-
sure. Compliance is calculated by dividing the volume
change (⌬V) by the change in detrusor pressure (⌬pdet)
during that change in bladder volume (C ⫽⌬V/⌬pdet). It is
expressed in ml/cm H
2
O.
Bladder compliance is a complicated entity in pediatric
practice for several reasons. 1) Compliance normally changes
according to bladder volume and, thus, it varies with age.
Therefore, compliance values should always be related to blad-
der capacity. 2) Detrusor pressure can be affected by the rate
of bladder filling, and so slow rates are preferred in children,
especially in infants. 3) There are no reliable reference val-
ues available for bladder compliance in infancy and child-
hood. A rule of thumb is that detrusor pressure 10 cm H
2
O
or less at expected bladder capacity for age is acceptable (see
below). Because bladder volumes vary during early life with
an increase from 30 ml at birth to approximately 300 ml as
a teenager, compliance tends to increase with age. In young
children and infants lower compliance values must be con-
sidered normal. More important than the numerical values
of bladder compliance is the shape of the filling curve, ie if it
is linear or nonlinear and, if nonlinear, in what way it
deviates from linearity. Because of this confusion, it is rec-
ommended that the actual measurements should be pro-
vided in all scientific publications.
Urethral function during filling cystometry. Urethral
function in children is usually assessed by pelvic floor EMG
using skin or, less commonly, needle electrodes. Urethral
closure pressure is rarely measured. At centers that use
pressure measurements the ICS definitions are applicable.
Urethral relaxation incontinence is defined as leakage
due to urethral relaxation in the absence of increased ab-
dominal pressure or detrusor overactivity. Although it is a
rare condition, it has been described in children and was
formerly called urethral instability.
16
Urodynamic stress incontinence is noted during filling cys-
tometry. It is defined as involuntary urine leakage during
increased abdominal pressure in the absence of a detrusor
contraction. Urodynamic stress incontinence is now the pre-
ferred term, not genuine stress incontinence. In children uro-
dynamic stress incontinence is a rare condition seen almost
exclusively in some girls with uropathy and neuropathy.
Abdominal leak point pressure is the intravesical pres-
sure at which urine leakage occurs due to increased abdom-
inal pressure in the absence of a detrusor contraction. De-
trusor leak point pressure excludes any abdominal
component to bladder emptying, such as straining, but it
includes voluntary sphincter tightening during voiding.
These are important definitions since high leak point pres-
sure indicates that there is a risk of upper urinary tract
damage. We propose that the term abdominal leak point
pressure should be used instead of the term Valsalva leak
point pressure, which carries the same meaning.
Pressure flow studies: Cystometric evaluations during
the voiding phase. Although pressure flow relationships
can be evaluated in infants and children, these measure-
ments are rarely made because of their low clinical rele-
vance in this age group.
Normal voiding is achieved by a continuous detrusor con-
traction that leads to complete bladder emptying within a
normal time span and in the absence of obstruction. Need-
less to say, in children before toilet training the contraction
need not be voluntarily initiated. For a given detrusor con-
traction the magnitude of the recorded pressure increase
depends on outlet resistance. This definition can be applied
to older children and adolescents. In infants high detrusor
pressures during voiding can be normal.
Detrusor underactivity, not to be confused with underac-
tive bladder, is a contraction of decreased strength and/or
duration, resulting in prolonged bladder emptying and/or
failure to achieve complete bladder emptying within a nor-
mal time span. An acontractile detrusor demonstrates no
contraction whatsoever during urodynamic studies. The 2
conditions can be observed in the clinical setting. They were
formerly called lazy bladder but are now referred to as
underactive bladder (see below).
Note that the highest detrusor pressure during voiding is
not identical to detrusor pressure during maximum urine
flow. These values are different between infants and older
children, and between males and females.
In infants and children urethral function during voiding
is most often measured by pelvic floor EMG recording using
primarily skin electrodes. This method provides only an
estimate of urethral and pelvic floor function but for diag-
nostic purposes in the pediatric setting it is usually suffi-
cient. More precise function may be achieved by needle elec-
trodes positioned in the sphincter with an analysis of
individual motor unit action potentials seen on an oscillo-
scopic screen.
Dysfunctional voiding is a urodynamic entity character-
ized by an intermittent and/or fluctuating uroflow rate due
to involuntary intermittent contractions of the striated mus-
cle of the external urethral sphincter or pelvic floor during
voiding in neurologically normal individuals. It is an en-
tirely different term from the term voiding dysfunction,
which is a generalized name that has been popularized to
denote any abnormality related to bladder filling and/or
emptying (see preface). The latter terminology should not be
used. Dysfunctional voiding is described under conditions
(see below). Detrusor-sphincter dyssynergia, which is appli-
cable in patients with neurogenic bladder disturbance, is the
cystometric observation of a detrusor voiding contraction
TERMINOLOGY FOR LOWER URINARY TRACT FUNCTION IN CHILDREN318
concurrent with an involuntary contraction of the urethra
and/or periurethral striated muscle. Occasionally the uri-
nary flow ceases. This must be distinguished from an invol-
untary detrusor contraction with a simultaneous increase in
sphincter EMG activity, ie the normal guarding reflex.
Briefly, dysfunctional voiding is a term applied to neuro-
logically intact children that requires uroflow measure-
ments, whereas detrusor-sphincter dyssynergia is used only
in the neuropathic setting and it requires invasive
urodynamics.
Four-Hour Voiding Observation
The 4-hour voiding observation is a new, scientifically vali-
dated technique used to evaluate bladder function in infancy.
17
The method implies continuous observation of a freely mov-
ing infant with frequent ultrasound measurement of bladder
filling and residual urine after each voiding. Voided volumes
may also be measured by weighing diapers.
Signs
Signs related to voided volume. The ICS and ICCS rec-
ommend that voided volume should replace the nebulous
term functional bladder capacity.
2
This choice of wording
underlines the fact that voided volumes vary greatly under
normal conditions and reflect bladder function more than
anatomy. However, we still need a standard for comparison
and this standard is termed EBC. EBC is estimated by the
formula, [30 ⫹ (age in years ⫻ 30)] in ml.
18,19
This formula
is useful up to age 12 years, after which age EBC is level at
390 ml. EBC is compared to the maximum voided volume
(with the addition of residual urine, if present and known),
as recorded in a bladder diary. Maximum voided volume is
considered small or large if found to be less than 65% or
greater than 150% of EBC, respectively (Appendix 6).
Residual urine. Residual urine is the amount of urine left
in the bladder immediately after voiding. The term is useful
at all ages. As mentioned above in more detail, normal
residual urine volume is zero, while 20 ml or more on repeat
measurements is pathological. Values between these 2 mea-
surements represent a borderline zone.
Signs related to urine output. Normal urine output is
difficult to define in childhood due to great intra-individual
and interindividual variation, and to a lack of large-scale
investigations.
20
While awaiting such investigations, we
propose that polyuria should be defined as a 24-hour urine
output of more than 2 l/m
2
body surface area. This is appli-
cable in children of all ages.
Nocturnal urine output excludes the last voiding before
sleep but includes the first voiding in the morning. In chil-
dren with enuresis urine voided during sleep is collected in
diapers and the change in diaper weight is measured. Noc-
turnal polyuria is a term relevant mainly in children with
nocturnal enuresis.
21
It is defined in this patient group as a
nocturnal urine output exceeding 130% of EBC for the age of
the child. The rationale for this definition is that a high
nocturnal urine output is only relevant if judged in relation
to the bladder. According to this definition nocturnal poly-
uria obviously results in nocturia or enuresis. However,
because of the necessary arbitrariness of this definition, we
strongly recommend that group studying these matters
should report nocturnal urine output and EBC or the ratios
between them, rather than merely defining children as hav-
ing polyuria or nonpolyuria.
We realize that some children with high 24-hour urine
output for renal or endocrinological reasons may still fail to
qualify for the above definition of nocturnal polyuria if the
bladder has accommodated and become large. However, in
these children the classification of polyuria into nocturnal or
diurnal is of little clinical relevance.
CONDITIONS
Enuresis
As mentioned in the symptoms section, enuresis is synony-
mous to intermittent nocturnal incontinence. It means in-
continence in discrete episodes while asleep. Enuresis (or
nocturnal incontinence) is a symptom and a condition.
Subgroups. With the growing awareness that children
with enuresis differ regarding comorbidity, treatment re-
sponse and pathogenesis a plethora of various subgrouping
strategies has been invented.
22–24
It is not yet clear if these
strategies may prove clinically relevant. Therefore, with the
exceptions given below the ICCS will not provide guidelines
for this.
There is ample evidence that children with enuresis who
have concomitant symptoms of LUT malfunction differ clin-
ically, therapeutically and pathogenetically from children
without such symptoms.
25
Therefore, an unequivocal and
universal subgrouping into monosymptomatic and non-
monosymptomatic enuresis on these grounds is essential.
The previous subdivision based on the presence or absence of
concomitant daytime incontinence alone is deemed inade-
quate since other daytime symptoms may also be indicative
of disturbed LUT function. The new subdivision is as fol-
lows. It is recommended that all groups whose studies of
enuresis are published should make this subdivision of their
patient material.
Enuresis in children without any other LUT symptoms
(nocturia excluded) and without a history of bladder dys-
function is defined as monosymptomatic enuresis. Other
children with enuresis and any other LUT symptoms are
said to experience nonmonosymptomatic enuresis. LUT
symptoms relevant to this definition are increased/de-
creased voiding frequency, daytime incontinence, urgency,
hesitancy, straining, a weak stream, intermittency, holding
maneuvers, a feeling of incomplete emptying, post-micturi-
tion dribble and genital or LUT pain.
Note also that, in contrast to the previous ICCS docu-
ment,
1
bedwetting in a child with concomitant daytime in-
continence is still called enuresis (or nocturnal inconti-
nence), although it belongs to the nonmonosymptomatic
variety.
If a subdivision is made according to the onset of enure-
sis, the term secondary enuresis should be reserved for chil-
dren who have had a previous dry period of at least 6
months.
26
Otherwise the term primary enuresis should be
used.
Daytime Conditions
The classification of daytime LUT conditions, especially con-
ditions with daytime incontinence as a central symptom, is
less straightforward than that of enuresis. The overlap be-
tween conditions is considerable, borderline cases are com-
TERMINOLOGY FOR LOWER URINARY TRACT FUNCTION IN CHILDREN 319
mon and the pathogenetic rationale for the grouping of var-
ious symptom complexes into specific conditions is often not
fully evidence based. Furthermore, there is often evolution
with time. For example, a child may start with urge incon-
tinence, continue through voiding dysfunction and voiding
postponement, and end with an underactive bladder.
To lessen this confusion and provide grounds for precise
definitions with greater pathogenetic and clinical relevance
the ICCS advises researchers studying these children to
assess and document 4 parameters in their patients, namely
1) incontinence (presence or absence and symptom fre-
quency), 2) voiding frequency, 3) voided volumes and 4) fluid
intake.
This is more important than subgrouping children into
the various recognized syndromes listed below. Obviously
the conditions, including incontinence, are applicable from
the age at which bladder control is attained or 5 years.
OAB and urge incontinence. We agree with the current
adult urology community practice of dropping the nebulous
term bladder instability
2
and replacing it with OAB. The
subjective hallmark of OAB is urgency and, thus, children
with this symptom can be said to have an OAB. Incontinence
is often also present, as is increased voiding frequency, but
these symptoms are not necessary prerequisites for the use
of the term OAB. The reason for not including increased
voiding frequency is that it is not at all clear if it carries any
clinical or pathogenetic significance, especially when fluid
intake is not considered. Children with OAB usually have
detrusor overactivity but this label cannot be applied to
them without cystometric evaluation (see above). Urge in-
continence simply means incontinence in the presence of
urgency and, thus, it is a term that is applicable to many
children with OAB.
Voiding postponement. Children with daytime inconti-
nence who are observed by their parents and/or caregivers to
habitually postpone micturition, often in specific situations,
using holding maneuvers are said to experience voiding
postponement. This is often associated with a low micturi-
tion frequency and a feeling of urgency due to a full bladder.
Some children have learned to restrict fluid intake as a
method of increasing voiding intervals and at the same time
decreasing incontinence. The rationale for the delineation of
this entity lies in the observation that these children often
experience psychological comorbidity or behavioral
disturbances.
27
Underactive bladder. The old entity lazy bladder is now
replaced by the neutral term underactive bladder. This term
is reserved for children with low voiding frequency and a
need to increase intra-abdominal pressure to initiate, main-
tain or complete voiding, ie straining. The children often
produce an interrupted pattern on uroflow measurement
and they are usually found to qualify for the term detrusor
underactivity if examined with invasive urodynamics.
Dysfunctional voiding. The child with dysfunctional void-
ing (this phrasing is preferred instead of voiding dysfunc-
tion) habitually contracts the urethral sphincter during
voiding. The term cannot be applied unless repeat uroflow
measurements show curves with a staccato pattern or un-
less verified by invasive urodynamic investigation. Note that
the term describes malfunction during the voiding phase
only. It says nothing about the storage phase. The use of this
expression to denote any kind of disturbed LUT function
28
leads to confusion and is strongly discouraged. Dysfunc-
tional voiding means dysfunction during voiding. Of course,
it is entirely possible for a child to experience dysfunctional
voiding as well as storage symptoms such as incontinence.
Obstruction. Children with a mechanical or functional,
static or phasic impediment to urine outflow during voiding
are said to experience LUT obstruction. It is characterized
by increased detrusor pressure and a decreased urine flow
rate. Different types of LUT obstruction in children are now
easy to describe and quantify using videourodynamic
techniques.
29
Stress incontinence. Stress incontinence is the leakage of
small amounts of urine at exertion or at increased intra-
abdominal pressure for various reasons. It is rare in neuro-
logically normal children. It should be differentiated from
incontinence in children who have postponed micturition
and do not get to the toilet in time, and wetting in children
with OAB in whom detrusor contractions may be provoked
by, for instance increased intra-abdominal pressure. The
term mixed incontinence, applied in patients with combined
urge incontinence and stress incontinence, is also rare in
childhood.
Vaginal reflux. Toilet trained prepubertal girls who expe-
rience incontinence in moderate amounts, consistently oc-
curring within 10 minutes after normal voiding, are said to
experience vaginal reflux if no underlying mechanism other
than vaginal entrapment of urine is obvious. This is not
associated with other LUT symptoms.
Giggle incontinence. Giggle incontinence is a rare syn-
drome in which apparently complete voiding occurs specifi-
cally during or immediately after laughing. Bladder function
is normal when the child is not laughing. The condition is to
be carefully differentiated from the much more common
situation when a child with OAB, voiding postponement or
underactive bladder experiences leakage during sudden
lapses of concentration, such as during laughter. The term
giggle incontinence should not be used in these cases.
Extraordinary daytime urinary frequency. This term
applies to children who void often and with small volumes
during the daytime only. Daytime voiding frequency is at
least once hourly and average voided volumes are less than
50% of EBC, usually much smaller. Incontinence is not a
usual or necessary ingredient in the condition and nocturnal
bladder behavior is normal for the age of the child. The term
is applicable from the age of daytime bladder control or 3
years.
COMORBIDITY
It is not the task of the ICCS to suggest definitions and
terminology for areas outside of the LUT. However, we find
it useful to list comorbid conditions that are relevant and
important to consider for researchers studying the LUT in
children. The conditions include constipation and encopresis
(Appendix 2), urinary tract infection, asymptomatic bacteri-
uria, vesicoureteral reflux, neuropsychiatric conditions (at-
TERMINOLOGY FOR LOWER URINARY TRACT FUNCTION IN CHILDREN320
tention deficit hyperactivity disorder, oppositional defiant
disorder, etc), learning disabilities and disorders of sleep
(sleep apneas and parasomnias).
TREATMENT
Definitions of Treatment Methods
Treatment in its widest sense refers to any intervention
that may or is done with the intent to alleviate symptoms
or eradicate a disturbance. Obviously this definition is
almost circular. The point is that treatment starts when a
caregiver first sees a patient. Even parts of the examina-
tion, such as the completion of a bladder diary or repeat
uroflow measurements, are also parts of treatment.
This document conveys definitions and guidelines re-
garding terminology alone. Recommendations for therapy
will be the subject of future communications. We strongly
advise writers not to use terms such as standard therapy
or maintenance therapy without defining what they in-
clude in these concepts.
Pharmacological and surgical therapy. Obviously this
means any therapy based on drugs or surgery.
Alarm treatment. Alarm treatment is therapy based on a
device that provides a strong sensory signal, usually but
not necessarily acoustic, immediately upon the occurrence
of incontinence. It can be used during the day or night,
although the latter use is more common.
Urotherapy. Urotherapy means nonsurgical, nonphar-
macological treatment for LUT malfunction. Thus, it is
synonymous with the term LUT rehabilitation, which is
frequently used in the adult sphere.
2
It encompasses a
wide field, incorporating many therapies used by uro-
therapists and other health care professionals. This reha-
bilitation approach and the therapies mentioned above
are certainly not mutually exclusive. Urotherapy can be
divided into standard therapy and specific interventions.
Standard urotherapy is noninterventional and it in-
cludes certain components, namely 1) information and
demystification, that is explanation about normal LUT
function and in what way the particular child deviates
from normal, 2) instruction about what to do about it, ie
regular voiding habits, sound voiding posture, avoiding
holding maneuvers, etc, 3) life-style advice regarding fluid
intake, the prevention of constipation, etc, 4) documenta-
tion of symptoms and voiding habits using bladder diaries
or frequency-volume charts, and 5) support and encour-
agement via regular followup by the caregiver.
Specific interventions used in the urotherapeutic set-
ting are defined in the same way as that published by the
ICS.
2
Thus, they are only mentioned in passing here. They
include various forms of pelvic floor training, behavioral
modification, biofeedback, electrical stimulation and
catheterization.
Urotherapy can include elements of cognitive behav-
ioral therapy, a type of psychotherapy including a wide
array of cognitive and behavioral modification techniques.
However, the term cognitive behavioral therapy should
not be used indiscriminately and without defining which
techniques to be used.
Definitions of Treatment Outcome
In the clinical situation the affected child and family
obviously are the ones to decide about the appropriate
criteria for treatment success. However, in the research
setting a uniform standard is necessary, so that studies
and treatment options can be compared with each other.
The only aim of this document is to facilitate comparison
among future studies. For more in-depth discussions of param-
eters of success and treatment outcome other texts can be
consulted.
30,31
Three basic principles should be recognized by re-
searchers. 1) Assessment of treatment outcome must be
based on pretreatment baseline documentation of symp-
tom frequency. 2) Actual symptom frequency during base-
line and treatment should be shown. This gives more
information than the grouping of children into responders
and nonresponders. 3) Different responses during and
after cessation of treatment must be clear. The latter may
sometimes reflect cure but the former never reflects it.
When children must be grouped together in subgroups
with varying degrees of treatment response for reasons of
comparison, it is suggested that the grouping should be
done as shown below. Percents shown reflect the decrease
in symptom frequency, ie a decrease in the number of wet
nights weekly.
Initial success. Nonresponse is defined as a 0% to 49%
decrease, partial response is defined as a 50% to 89%
decrease, response is defined as a 90% or greater decrease
and full response is defined as a 100% decrease or less
than 1 symptom occurrence monthly.
Long-term success. Relapse is defined as more than 1
symptom recurrence monthly, continued success is de-
fined as no relapse in 6 months after the interruption of
treatment and complete success is defined as no relapse in
2 years after the interruption of treatment.
APPENDIX 1
Other experts
Paul Abrams, David A. Bloom, Richard Butler, Marc Cendron, Jonathan
Evans, Tom de Jong, David Joseph, Ulla Sillén and others.
APPENDIX 2
Encopresis and functional fecal incontinence
Urinary and fecal incontinence often coexist in different combinations.
Therefore, it is advisable to focus on comorbidity and describe any type of
nocturnal enuresis, daytime urinary incontinence and fecal incontinence.
In other words, 1 child might have 3 conditions and diagnoses at the same
time and each should be named. General and unspecific terms such as
elimination syndrome should be avoided for these combined disorders.
It is not the aim of this Appendix to provide a full standardization of
relevant terminology for encopresis and functional fecal incontinence.
Therefore, only definitions of the main conditions are provided but not of
signs and symptoms. Definitions are provided in accordance with other
specialties, such as pediatric gastroenterology and child psychiatry, dealing
with children with these disorders.
32
Fecal incontinence is an umbrella term encompassing any sort of depo-
sition of feces in inappropriate places, functional and organic.
Anal incontinence is a general term including inappropriate passage of
feces and of flatulence, functional and organic.
Organic fecal incontinence results from neurological, structural or other
organic causes.
Functional fecal incontinence can be used as a synonym for encopresis.
(appendix continued)
TERMINOLOGY FOR LOWER URINARY TRACT FUNCTION IN CHILDREN 321
APPENDIX 2 continued
Encopresis
According to the ICD-10
33
and the DSM-IV
34
encopresis is defined as volun-
tary and involuntary passage of feces in inappropriate places in a child 4 years
or older after organic causes have been ruled out. It must occur at least once
monthly for a duration of 6 months (ICD-10) or 3 months (DSM-IV).
Primary encopresis denotes that the longest clean interval was shorter
than 6 months.
Secondary encopresis is defined by a relapse after a clean period of 6
months or longer without signs or symptoms.
In the subtype encopresis with constipation (synonyms: encopresis with
constipation and overflow incontinence [DSM-IV], retentive encopresis and
functional retentive [or constipation associated] fecal incontinence) enco-
presis and constipation are present.
In the subtype encopresis without constipation (synonyms: encopresis
without constipation and overflow incontinence [DSM-IV], functional non-
retentive [or nonconstipation associated] fecal incontinence and solitary
encopresis) encopresis but no constipation is present.
Soiling is a confusing and poorly defined term that should not be used in
view of established international definitions of encopresis (ICD-10 and
DSM-IV) or functional fecal incontinence.
Constipation
There are no good definitions of constipation. It cannot be defined by a low
defecation frequency alone but requires additional signs and symptoms, such
as painful defecation, palpable abdominal masses, formed stool masses during
rectal examination, abdominal pain and typical ultrasound findings, such as
enlarged rectal diameters and retrovesical impressions. Typical definitions
include that of the North American Society for Pediatric Gastroenterology and
Nutrition: “a delay or difficulty in defecation, present for two or more weeks
and sufficient to cause distress to the patient.”
35
Functional constipation is defined by “scybalous, pebble-like, hard stools
for a majority of stools; by firm stools two or less times per week; and by the
absence of structural, endocrine or metabolic disease” according to Rome-II
criteria.
36
Only 5% of all cases of constipation are due to organic causes and
95% are functional. For research purposes it is best to describe defecation
frequency as well as all associated signs and symptoms.
Chronic constipation has been defined by the Paris Consensus on Child-
hood Constipation Terminology Group by the occurrence of 2 or more of the
following characteristics during the last 8 weeks): fewer than 3 bowel
movements weekly, greater than 1 episode of fecal incontinence weekly,
large stools in the rectum or palpable on abdominal examination, passing
of stools so large that they may obstruct the toilet, display of retentive
posturing and withholding behaviors and/or painful defecation.
37
Functional fecal retention consists of repetitive attempts to avoid defecation
because of fears associated with defecation. Consequently a fecal mass accu-
mulates in the rectum. It is defined by the passage of large diameter stools and
retentive posturing for at least 12 weeks.
36
This term is deemed redundant by
the Paris Consensus on Childhood Constipation Terminology Group because it
is included in the definition of chronic constipation.
36
Toilet refusal syndrome occurs in children who use the toilet for micturi-
tion but insist on using a diaper for defecation.
Toilet phobia is an isolated phobia in children who fear using the toilet
for micturition and for defecation.
APPENDIX 3
Alphabetical list of commonly used terms defined
in the ICCS terminology
This list is neither complete nor detailed but is expected to be useful as a
quick reference list for terms that are not rare or self-explanatory.
Bladder diary: a standard chart to be completed by the child or family,
used for evaluation of bladder function and including data regarding at
least voided volumes, voiding frequency, fluid intake, nocturia, enuresis
and incontinence episodes.
Daytime voiding frequency, decreased: 3 or fewer voidings per day.
Daytime voiding frequency, increased: 8 or more voidings per day.
Detrusor overactivity: the observation during cystometry of involuntary
detrusor contractions during the filling phase. This replaces the term
detrusor instability.
Detrusor-sphincter dyssynergia: the cystometric observation of a detrusor
voiding contraction concurrent with an involuntary contraction of the urethra.
Detrusor underactivity: the cystometric observation of a contraction of
decreased strength and/or duration, resulting in prolonged bladder empty-
ing and/or a failure to achieve complete bladder emptying.
Dysfunctional voiding: the habitual contraction of the urethral sphincter
during voiding, as observed by uroflow measurements.
Enuresis: intermittent incontinence of urine while sleeping, ie synony-
mous with (intermittent) nocturnal incontinence. The term is used regard-
less of whether daytime incontinence or other lower urinary tract symp-
toms is also present. Nocturnal may be added for extra clarity.
(appendix continued)
APPENDIX 3 continued
Enuresis, monosymptomatic: enuresis in a child without any (other)
lower urinary tract symptoms.
Enuresis, nonmonosymptomatic: enuresis in a child with (other) lower
urinary tract symptoms, such as daytime incontinence, urgency, holding
maneuvers, etc.
Enuresis, primary: enuresis in a child who has previously been dry for
less than 6 months.
Enuresis, secondary: enuresis in a child who has previously been dry for
at least 6 months.
Expected bladder capacity: age related expected maximum voided vol-
ume, as calculated via the formula, [30 ⫹(age in years ⫻30)] in ml and
used as a standard for comparisons.
Frequency-volume chart: a chart to be completed by the child or family
used for evaluation of bladder function but not including all data required
of a bladder diary. See above.
Incontinence, continuous: continuous leakage of urine, not in discrete
portions, which indicates malformation or iatrogenic damage.
Incontinence, intermittent: leakage of urine in discrete portions during
the day and/or night.
Incontinence, nocturnal: see enuresis.
Overactive bladder: the condition afflicting patients experiencing ur-
gency symptoms. It replaces the term bladder instability.
Polyuria, nocturnal: nocturnal urine output exceeding 130% of expected
bladder capacity. See above.
Residual urine: urine left in the bladder after voiding. Residual urine in
excess of 5 to 20 ml indicates incomplete bladder emptying.
Underactive bladder: the condition afflicting patients with low voiding
frequency and the need to increase intra-abdominal pressure to void. It
replaces the term lazy bladder.
Urge incontinence: incontinence in patients experiencing urgency, ie
incontinence in children with overactive bladder.
Voided volume: voided volume at micturition, as documented in a bladder
diary. It replaces the term bladder capacity.
Voided volume, maximum: the largest voided volume, as documented in
a bladder diary. It replaces the term functional bladder capacity.
Voiding postponement: incontinence in the presence of habitual holding
maneuvers.
APPENDIX 4
Urodynamic instruments in children
Instrument Age Data
Bladder diary From 5 years Voided volumes
Voiding frequency
Urine output
Symptom (leakage, etc) frequency
Other data (Appendix 5)
Uroflow and
residual
From 5 years Voided volume
Curve shape
Urine flow rate
Residual urine
Cystometry All ages Detrusor pressure and activity
Cystometric bladder capacity
Compliance
Sphincter competence and activity
Other data (see specific section)
4-Hour
voiding
observation
Infancy Voided volumes
Voiding frequency
Residual urine
Observation of symptoms
APPENDIX 5
The bladder diary (data to be included and
information that can be extracted)
Data to be
Included
Duration of
Documentation*
Information That Can be
Extracted
Voidings: timing
and volumes
Minimum 48 hours
(including nocturia
volumes)
Voiding frequency
Daytime urine output (if no or
small amounts of
incontinence urine, or pad
testing performed)
The 24-hour urine output (if
no enuresis or enuresis
volumes measured)
Average voided volume
Maximum voided volume
(appendix continued)
TERMINOLOGY FOR LOWER URINARY TRACT FUNCTION IN CHILDREN322
APPENDIX 5 continued
Data to be
Included
Duration of
Documentation*
Information That Can be
Extracted
Nocturia
episodes
14 Nights Nocturia frequency
Daytime
incontinence
episodes
14 Days Incontinence frequency
Enuresis
episodes
14 Nights Enuresis severity
Enuresis urine
volumes†
7 Nights Presence or absence of
nocturnal polyuria
Other LUT
symptoms
14 Days Symptom frequency
Fluid intake
volume, timing
and type of
fluid intake‡
Minimum 48 hours The 24-hour fluid intake
Fluid intake pattern
Bedtime and
awakening
time§
14 Days Time spent in bed
Bowel
movements储
14 Days Defecation frequency
Encopresis储14 Days Encopresis severity
* Compromise between what is scientifically validated
9–11
and what is
deemed practical without undue risk of noncompliance and study dropout.
† Implies measurement of weight of diapers or bedclothes and can be
omitted if no urine output assessment is deemed necessary.
‡ Since urine output equals fluid intake minus insensible perspiration,
these data are needed for good urine output interpretation.
§ Recommended but not mandatory.
储Needed when encopresis or any constipation symptom is present.
APPENDIX 6
Maximum voided volume formula
Note that the formula was not acquired from a population based study of
completely normal children and, therefore, EBC should not be regarded as
normal maximum voided volume. Strictly speaking normal maximum
voided volume is not known. The formula is chosen for practical purposes
and simplicity, and because it is widely known and used.
Abbreviations and Acronyms
DSM ⫽Diagnostic and Statistical Manual of
Mental Disorders
EBC ⫽expected bladder capacity
EMG ⫽electromyography
ICCS ⫽International Children’s Continence Society
ICD ⫽International Classification of Diseases
ICS ⫽International Continence Society
LUT ⫽lower urinary tract
OAB ⫽overactive bladder
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