Article

Factor Structure of a Sluggish Cognitive Tempo Scale in Clinically-Referred Children

Department of Neuropsychology, Kennedy Krieger Institute, 1750 E. Fairmount Ave., Baltimore, MD, 21231, USA, .
Journal of Abnormal Child Psychology (Impact Factor: 3.09). 05/2012; 40(8):1327-37. DOI: 10.1007/s10802-012-9643-6
Source: PubMed
ABSTRACT
"Sluggish cognitive tempo" (SCT) is a construct hypothesized to describe a constellation of behaviors that includes daydreaming, lethargy, drowsiness, difficulty sustaining attention, and underactivity. Although the construct has been inconsistently defined, measures of SCT have shown associations with symptoms of attention-deficit/hyperactivity disorder (ADHD), particularly inattention. Thus, better characterization of SCT symptoms may help to better predict specific areas of functional difficulty in children with ADHD. The present study examined psychometric characteristics of a recently developed 14-item scale of SCT (Penny et al., Psychological Assessment 21:380-389, 2009), completed by teachers on children referred for outpatient neuropsychological assessment. Exploratory factor analysis identified three factors in the clinical sample: Sleepy/Sluggish, Slow/Daydreamy, and Low Initiation/Persistence. Additionally, SCT symptoms, especially those loading on the Sleepy/Sluggish and Slow/Daydreamy factors, correlated more strongly with inattentive than with hyperactive/impulsive symptoms, while Low Initiation/Persistence symptoms added significant unique variance (over and above symptoms of inattention) to the predictions of impairment in academic progress.

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Available from: Ariana Tart-Zelvin, Mar 31, 2014
Factor Structure of a Sluggish Cognitive Tempo Scale
in Clinically-Referred Children
Lisa A. Jacobson & Sarah C. Murphy-Bowman &
Alison E. Pritchard & Ariana Tart-Zelvin &
T. Andrew Zabel & E. Mark Mahone
#
Springer Science+Business Media, LLC 2012
Abstract Sluggish cognitive tempo (SCT) is a construct
hypothesized to describe a constellation of behaviors that
includes daydreaming, lethargy, drowsiness, difficulty sus-
taining attention, and underactivity. Although the construct
has been inconsistently defined, measures of SCT have
shown associations with symptoms of attention-deficit/
hyperactivity disorder (ADHD), particularly inattention.
Thus, better characterization of SCT symptoms may help
to better predict specific areas of functional difficulty in
children with ADHD. The present study examined psycho-
metric characteristics of a recently developed 14-item scale
of SCT (Penny et al., Psychological Assessment 21:380
389, 2009), completed by teachers on children referred for
outpatient neuropsychological assessment. Exploratory factor
analysis identified three factors in the clinical sample: Sleepy/
Sluggish, Slow/Daydreamy, and Low Initiation/Persistence.
Additionally, SCT symptoms, especially those loading on
the Sleepy/Sluggish and Slow/Daydreamy factors, correlated
more strongly with inattentive than with hyperactive/impul-
sive symptoms, while Low Initiation/Persistence symptoms
added significant unique variance (over and above symptoms
of inattention) to the predictions of impairment in academic
progress.
Keywords ADHD
.
Rating scale
.
Inattention
.
Hyperactivity
.
Academic performance
.
Reliability
.
Validity
ADHD and SCT
Attention-deficit/hyperactivity disorder (ADHD) is one of the
most frequently diagnosed neur odevelo pmental disorders
(Centers for Disease Control and Prevention [CDC], 2010),
commonly diagnosed in childhood and often persisting into
adulthood (Kessler et al. 2005). The current Diagnostic and
Statistical Manual of Mental Disorders, Fourth Edition, Text
Revision (DSM-IV), characterizes ADHD as having three
subtypes: Hyperactive-Impulsive, Inattentive, and Combined
(American Psychiatric Association 2000). Categorical repre-
sentation of ADHD subtypes has been questioned, however,
as evidence suggests that not only are the subtypes themselves
heterogeneous (e.g., Elia et al. 2009; Goth-Owens et al. 2010),
but the diagnostic symptoms are also developmental phenom-
ena that change over time (Lahey et al. 2005; Larsson et al.
2011). For example, individuals within the Inattentive subtype
may actually include children who previously met criteria for
Hyperactive-Impulsive or Combined subtypes, but have
aged out of their hyperactive symptomatology (Lahey et
al. 2005; Larsson et al. 2011), or those children who are just
subthreshold (with regard to Hyperactive-Impulsive symp-
toms) for the Combined subtype. Not surprisingly, research
comparing neurobehavioral and neuropsychological function
among children with different ADHD subtypes has been
inconsistentoften failing to identify meaningful differences
(e.g., Riccio et al. 2006; Riley et al. 2008).
Children demonstrating symptoms of the Inattentive sub-
type have also been described as displaying characteristics of
sluggish cognitive tempo (SCT), a construct characterized by
dif
fic
ulty sustaining attention, daydreaming, lethargy, physical
L. A. Jacobson (*)
:
S. C. Murphy-Bowman
:
A. E. Pritchard
:
A. Tart-Zelvin
:
T. A. Zabel
:
E. M. Mahone
Department of Neuropsychology, Kennedy Krieger Institute,
1750 E. Fairmount Ave.,
Baltimore, MD 21231, USA
e-mail: jacobson@kennedykrieger.org
L. A. Jacobson
:
A. E. Pritchard
:
T. A. Zabel
:
E. M. Mahone
Department of Psychiatry and Behavioral Sciences,
Johns Hopkins University School of Medicine,
Baltimore, MD, USA
J Abnorm Child Psychol
DOI 10.1007/s10802-012-9643-6
Page 1
underactivity, slowed movement, and decreased responsive-
ness (Carlson and Mann 2002; Garner et al. 2010). While
diagnostic criteria for the ADHD-Inattentive subtype an d
SCT overlap, there is emerging evidence that some features
of the SCT phenotype may be distinct from inattention, per-
haps related to anomalous development of ventral prefrontal,
right superior temporal, and posterior-inferior parietal cortices
areas which have been differentially implicated in regulation of
attention in children with primarily Inattentive ADHD (Solanto
et al. 2009), and may add unique variance in predicting neuro-
behavioral function, beyond that attributable to ADHD symp-
tomatology (Murphy-Bowman et al. 2011). A confirmatory
factor analysis of teacher and parent symptom ratings of SCT,
inattention, and hyperactivity-impulsivity found that a three-
factor solution fit the data best, suggesting that SCT and
inattention represent distinct factors (Hartman et al. 2004);
however, others have found SCT and inattentive symptoms
to load together on the same factor (e.g., Todd et al. 2004),
suggesting that further clarification is needed.
Within the Inattentive subtype, children with higher levels
of SCT symptomatology have been found to show less exter-
nalizing behavior, but higher levels of unhappiness, withdraw-
al, anxiety/depression, and social dysfunction relative to
children with lower levels of SCT symptomatology, suggest-
ing a possible link between SCT and mood symptoms
(Carlson and Mann 2002; Hartman et al. 2004). Garner and
colleagues (2010) investigated the association between SCT
and adjustment symptoms within a clinically-referred sample,
finding that parent- and teacher-reported SCT symptoms were
only weakly correlated (r0 0.28 and 0.22, respectively) with
ratings on the Anxious/Depressed scale of the Child Behavior
Checklist (CBCL; Achenbach 1991; Achenbach and Rescorla
2007), with parent ratings of SCT correlating to a similar
degree with ratings on the CBCL Aggressive behavior scale
(r0 0.20). In their sample, SCT ratings correlated more strongly
with ratings of inattention (r0 0.42 and 0.55, for parent and
teacher ratings, respectively). Similarly, a recently published
abstract found parent ratings of SCT symptoms to have more
overlap with ratings of inattention than with ratings of anxiety
in a community sample of children with ADHD and typically-
developing controls (Murphy-Bowman et al. 2011). Moreover,
higher levels of SCT symptoms were predictive of slowed
processing speed, even after controlling for symptoms of
inattention.
Measurement of SCT
Although there is a growing body of work validating the
SCT construct, and interest in better spe cification of the
Inattentive ADHD subtype in the upcoming DSM-V (Ameri-
can Psychiatric Association 2010; Coghill and Seth 2011),
there is little consensus regarding definition or measurement
of these characteristics. Several studies have extracted items
from the Child Behavior Checklist (CBCL; Achenbach 1991;
Achenbach and Rescorla 2007) to study behaviors associated
with SCT. Hartman et al. (2004) examined parent- and teacher-
rated symptoms of SCT in a community sample, using five
items on the CBCL believed to be characteristic of the con-
struct, including: confused or seems to be in a fog;”“day-
dreams or gets lost in his/her thoughts;”“stares blankly;
underactive, slow moving, or lacks energy; an
d s
luggish/
slow to respond. Using these items, SCT symptoms were
dissociated from symptoms of ADHD, although teacher rat-
ings showed a stronger association between SCT and inatten-
tion while parent ratings suggested that both Inattentive and
Combined subtypes showed significant SCT symptomatology
(Hartman et al. 2004). In 2007, a new 4-item subscale to assess
Sluggish Cognitive Tempo was formally included on the
CBCL, including items used in earlier studies of SCT
(Achenbach and Rescorla 2007). Using the CBCL SCT scale
with parents and teachers in a clinical sample, Garner et al.
(2010) found that children with the Inattentive subtype were
rated as showing more symptoms of SCT than children with
the Combined subtype, although both ADHD subtypes had
higher SCT symptoms than a no-diagnosis group. Wahlstedt
and Bohlin (2010) investigated teacher ratings of SCT in a
non-referred, community-based sample in Sweden, using five
SCT items from the CBCL teacher rating form. Symptoms of
SCT and symptoms of DSM-IV-defined inattention were
highly correlated; however, SCT was more strongly associated
than DSM-IV-defined inattention with performance on meas-
ures of sustained attention than with inhibitory control. Re-
cently, construct validity of the CBCL SCT subscale was
examined using parent ratings in a sample of children with
and without ADHD (Murphy-Bowman et al. 2011). Consis-
tent with prior studies examining associations between SCT
and ADHD-related symptomatology, the SCT scale was more
strongly correlated with measures of similar constructs
such as inattention and performance on timed tasks, than
with measures of dissimilar constructs such as untimed verbal
tasks or internalizing behaviors. Ratings on the SCT scale also
uniquely predicted slowing in childrens processing speed,
after controlling for inattentive and hyperactive/impulsive
symptomatology.
Noting the limitations of a 4- or 5-item rating scale, other
researchers have developed measures assessing SCT-specific
symptomatology in more depth. For example, McBurnett and
Pfiffner 2005, in Pfiffner et al. (2007) developed a 15-item
measure of SCT symptoms, including such items as day-
dreams,”“stares into space,”“loses cognitive set, and
moves slowly. In a sample of children referred to an ADHD
specialty clinic, this 15-item scale showed good internal con-
sistency (Cronbachs alpha0 0.90) as reported in Pfiffner et al.
(2007). Unfortunately, no additional normative or psychomet-
ric data are available for this measure. More recently, Penny et
J Abnorm Child Psychol
Page 2
al. (2009) developed a 14-item scale of symptoms believed to
represent the SCT construct. Items included apathetic, shows
little interest in things or activities;”“lacks initiative to com-
plete work;”“effort on tasks fades quickly; and seems to be
in a world of his or her own. In a preliminary validation study
with a large sample of typically developing Canadian school
children, this scale was found to reliably assess symptoms of
SCT, with parent and teacher ratings suggesting a multi -
factorial structure. Consistent with prior research, all of the
subscales on this measure we re found to correlate more
strongly with inattentive than hyperactive symptoms of
ADHD; however, SCT symptoms were also more strongly
associated with internalizing symptomatology than were inat-
tentive symptoms. Given the literature to date, the Penny et al.
14-item SCT scale may represent the most comprehensive and
promising measure of the SCT construct, although it has not
yet been examined within a clinical population or within a
United States sample.
In sum, although research investigating SCT is emerging,
with clear implications for proposed diagnostic criteria for
ADHD in the DSM-V, the construct has not been consis-
tently defined. Thus, to date, there is no clear consensus
regarding measurement. Currently, there are few published
studies or measures of SCT, and those studies that exist have
used a heterogeneous approach to item content and depth of
coverage, sampling, and raters. Additionally, to our knowl-
edge, few studies have examined whether the pattern of SCT
symptoms in a typically developing community sample
differs from the pattern seen in a clinically referred sample
(e.g., Garner et al. 2010). Finally, even fewer studies have
examined teacher ratings of the construct in a clinical sam-
ple. Teacher ratings may be especially relevant to diagnosis
of ADHD, not only due to the requirement that symptoms
be present across settings, but also as teachers regularly
observe children completing less preferred and often effort-
ful tasks tasks which are most likely to elicit difficulties
with attentional regulation.
Given these considerations, the purpose of the present
study was to examine teacher ratings on the Penny et al.
(2009) Sluggish Cognitive Tempo scale in a clinically re-
ferred sample. This scale was chosen because it appears
promising, with published normative data and established
preliminary validity in typically developing children. The
present study examined whether the factor structure identi-
fied in the original validity study in Canada was consistently
observed in a sample of clinically referred children within
the U.S. We hypothesized that, given the strong overlap
between SCT and inattentive ADHD symptoms, the factor
structure of teacher ratings from a clinical sample might
differ from the two-factor solution described in the commu-
nity sample (Penny et al. 2009), as greater variability of
symptom presentation is possible within a referred sample.
Furthermore, we also hypothes ized that the pattern of
specific associations between SCT subscales and ADHD
symptomatology would differ, with a ll SCT subscales show-
ing stronger associations with the inattentive symptomatol-
ogy than with hyperactive-impulsive symptoms.
Methods
Procedures
As part of routine clinical practice at a large outpatient neuro-
psychology assessment center, parents of children referred to
the clinic request that their childs teacher complete a set of
behavioral rating scales [including the Penny et al. (2009)
SCT scale, the ADHD Rating Scale-IV (DuPaul et al. 1998),
portions of the Vanderbilt Assessment Scales (Wolraich et al.
1998), and the Fabiano et al. (2006) Impairment Rating Scale]
through a secure online survey engine prior to assessment. All
questionnaire data were subsequently entered into the depart-
mental clinical database. Following approval from the Insti-
tutional Review Board, the clinical database was queried and
de-identified data were extracted for any child for whom
teacher ratings on the SCT scale, ADHD Rating Scale-IV,
Vanderbilt, and the Impairment Rating Scale were available.
Additional data extracted from the clinical dataset included
age, sex, race, ethnicity, and medication status. Using this data
extraction method, teacher ratings from a total of 143 children
were included in the analyses.
Study Measures
Sluggish Cognitive Tempo (SCT) Scale (Penny et al. 2009)
The SCT scale is a 14-item teacher- or parent-report rating
scale of symptoms that correspond to the SCT construct.
Ratings are made on a four-point Likert scale (0 0 Never or
Rarely; 1 0
Sometimes; 2 0 Often;
3 0 V
ery Often). Teacher
ratings were used for the present investigation. The scale
was originally normed on a Cana dian samp le of scho ol
children, and data from teacher reports in this sample
yielded two factors, Slow and Sleepy/Daydreamer, account-
ing for 74.6 % of the variance. Internal consistency ranged
between 0.93 and 0.96. Test-retest reliability estimates were
not published for the teacher-report form, but estimates for
the parent-report version were adequate (ranging from 0.70
to 0.87). Total composite score for the SCT scale is the sum
of the ratings on all 14 items.
ADHD Rating Scale-IV, School Version (DuPaul et al.
1998) The ADHD Rating Scale-IV is an 18-item measure,
reflecting the DSM-IV ADHD diagnostic criteria. The scale
is designed to be completed by parents or teachers, although
for the purposes of the current study, only the school version
was used. Item content reflects DSM-IV diagnostic criteria
J Abnorm Child Psychol
Page 3
and items were rated based on the childs behavior over the
past 6 months, using a four-point Likert scale (0 0 Not at all;
1 0 Sometimes; 2 0 Often; 3 0 Very Much). Subsca les
correspond to the DSM-IV Inattentive and Hyperactive/
Impulsive criteria. Total subscale scores were obtained by
adding item ratings (range: 027 for each). The ADHD Rating
Scale-IV has been shown to demonstrate adequate reliability
and validity (DuPaul et al. 1998); internal consistency esti-
mates for the school version ranged from 0.88 to 0.94, with
test-retest reliability over short periods of time ranging from
0.88 to 0.90. In the current sample, internal consistency for the
ADHD Rating Scale-IV subscales was excellent (Inattention
alpha0 0.90; Hyperactivity/Impulsivity alpha0 0.92).
Based on teacher ratings on the ADHD Rating Scale-IV,
children were identified as displaying a high level of behav-
ioral symptoms, consistent with behavioral criteria (using
symptom counts based upon items endorsed as often or
very much true) characteristic of the DSM-IV ADHD sub-
types. Specifically, children for whom teachers endorsed at
least six symptoms of inattention, but fewer than six symptoms
of hyperactivity/impulsivity were considered as likely to dis-
play a presentation characterized by high levels of Inattention
(or the high-Inattentive symptomatology group; high-I); chil-
dren with at least six symptoms of hyperactivity/impulsivity
but fewer than six symptoms of inattention were considered to
display behaviors characterized by high levels of Hyperactiv-
ity/Impulsivity (or the high-Hyperactive/Impulsive symptom-
atology group; high-H/I); and children for whom teachers
endorsed at least six symptoms of both inattention and hyper-
activity/impulsivity were considered to present with symptom-
atology characterized by high levels of both types of behaviors
(or the high-Combined symptomatology group; high-C). In
each case, although
no formal diagnosis of ADHD was made
as data from multiple settings were not available, for the
purposes of this study, the level of perceived behavioral symp-
tomatology, according to teachers, was used to group children
as primarily characterized by a particular behavioral presenta-
tion: high-I, high-H/I, or high-C for initial analyses. Children
rated as showing fewer than six symptoms of both inattention
and hyperactivity/impulsivity were considered to fall into the
low symptomatology group (Low-Symptoms).
Vanderbilt Assessment Scale, Teacher Version (Wolraich et
al. 1998) The Vanderbilt Assessment Scale is an observer-
report measure of behavioral symptoms; for the purposes of
this study, only the teacher-report version was used. Specifi-
cally, the seven items designed to assess for internalizing
behavior symptoms suggestive of anxiety or depression were
included to provide an estimate of internalizing symptoms
(e.g., is fearful, anxious, or worried; feels worthless or inferior;
is sad, unhappy, or depressed). Items are rated on a four-point
scale (0 0 Never; 1 0 Occasionally; 2 0 Often; 3 0 Very Often).
The anxiety score is the sum of ratings on the three anxiety
symptom items (range0 0to9);thedepressionscoreis
the sum of ratings on the four items assessing depres-
sive symptomatology (range0 0to12).Inthissample,
internal consistency for the Vanderbilt affective scales
was good: Anxiety i tems/scale alpha0 0.84; Depression
items/scale alpha0 0.86.
Impairment Rating Scale (IRS; Fab iano et al. 2006 ) The
Impairment Rating Scale is a brief observ er-rated measure
assessing the impact of a childs behavioral problems on
specific domains of functioning. Raters were asked to quan-
tify (on a 0 to 6 scale) the degree to which behavioral
difficulties affect the childs functioning across academic
(e.g., academic progress), social (e.g., relationships with
peers and adults), and personal (e.g., self-esteem) domains.
For the online version of this measure, teachers were asked
to check a box on a 0 to 6 s cale, i ndic ating a scend ing
severity, which corresponded to the degree to which the
child s behavioral problems were felt to limit his or her
academic progress. The IRS demonstrated adequate initial
stability over a period of 2 to 6 months and adequate
convergent and discriminant validity in identifying children
with ADHD (Fabiano et al. 2006). The overall IRS score
correlated with ADHD symptomatology, as rated by both
parents and teachers.
Data Analysis
Exploratory factor analysis was conducted on the 14 items
of the SCT scale, completed by teachers, to determine
whether the component structure of the measure within a
clinically referred population was consistent with that
reported in the original community-base d sample. Factors
were extracted using principal axis factoring analysis, with
Promax rotation. Next, the pattern of associations among
total ADHD symptomatology, behavioral subtypes (defined
by number of symptoms endorsed by teachers on the ADHD
Rating Scale-IV), and SCT total and factor scores were
examined. SCT symptomatology was examined across
groups, including behavioral subtypes, using an ANOVA
to determine whether the pattern of SCT symptomatology
differed for children characterized by different behavioral
presentations. Finally, hierarchical regression analyses were
used to determine the association between SCT scale factors
and teacher-rated school functioning.
Results
Sample
The sample included 143 children consecutively referred for
clinical neuropsychological evaluation at an outpatient
J Abnorm Child Psychol
Page 4
hospital-based clinic, for whom teacher ratings were avail-
able (age M0 9.18, SD0 3.02, range: 318 years). In this
sample, the maj ority (n0 114) of children fell between ages
5and11(i.e.,elementaryschoolage).Fourwerepre-
schoolers and the remainder of the sample (n0 25) was older.
The majority were male (67 %) and Caucasian (51.7 %);
16.8 % were African-American, 4.2 % Asian, 0.7 % were
multiracial, and 17.5 % of other racial backgrounds or un-
known. Five participants (3.5 %) were of parent-reported
Hispanic ethnicity. Additionally, medication data were avail-
able for 136 of the 143 participants. Of those for whom this
information was provided, 29 (21.3 %) were prescribed stim-
ulant medic ations and 10 (7.4 %) were prescribed n on-
stimulants (these groups are not exclusive as some children
were reported ly p rescribed both types of medication
simultaneously).
Using the descriptive criteria outlined above for categor-
ical characterization of the sample according to level of
perceived behavioral symptomatology, 59.4 % (n0 85) of
the sample fell into the Low-Symptoms group, based on
teacher ratings. Of those reported to exhibit a relatively high
level of symptomatology (40.6 %; n0 58), 63.8 % (n0 37)
fell into the high-I group, 13.8 % (n0 8) fell into the high-H/
I group, and 22.4 % (n0 13) fell into the high-C group.
Factor Structure of the SCT Scale
Initial internal consistency of the SCT scale items in this
clinical sample was excellent and comparable with that
found in the initial validation study (Cr onbachs alpha0
0.93). Exploratory factor analysis, using principal axis fac-
toring with Promax (oblique) rotation, of teacher ratings on
the SCT scale items extracted three factors which accounted
for 68.03 % of the total variance; the first factor accounted
for 50.32 % of the variance, factor 2 accounted for an
additional 11.64 %, and factor 3 accounted for 6.07 % of
the variance. Facto rs were determined to be signifi cant
based upon eigenvalues above 1.0 and examination of the
scree plot. There were very min imal cross loadings between
factors (see Table 1), with only one item (appears lethar-
gic) loading strongly on more than one factor. Based on
item loadings, and using terminology proposed by the scale
authors, factor 1 can be described as a Sleepy/Sluggish
factor (e.g., appears to be sluggish, appears lethargic, is
underactive/lacks energy), factor 2 represents Slow/Day-
dreamy be h av io r s ( e.g . , g et s lo st in own thoug ht s , day -
dreams, is slow or delayed in completing tasks), and factor
3 describes poor effort or Low Initiation/Persistence (e.g.,
effort fades quickly, la cks init iative to c omplete w ork).
Factor scores for each individual on the three factors were
calculated from the factor loadings, saved as variables fol-
lowing the factor analysis.
As an additional step, Comprehensive Exploratory Factor
Analysis (CEFA; Browne et al. 2008) was undertaken to
provide additional information regarding the fit of the factor
structure in these data. Using CEFA with oblique rotation
(GEOMIN), three possible factor solutions were examined:
a 2-factor, 3-factor, and 4-factor solution. CEFA provides a
variety of fit statistics that suggest that while the 4-factor
solution provides a relatively better fit to these data
(RMSEA0 0.068, Χ
2
0 68.16) compared to a 3-factor solu-
tion (RMSEA0 0.116, Χ
2
0 151.83) or a 2-factor solution
(RMSEA0 0.162, Χ
2
0 301.45), the 4-fact or solution yields
a fourth factor consisting of only two items, a less than ideal
solution. In the 4-factor solution, two of the factors (the
Sleepy/Sluggish and Low Initiation/Persistence factors) are
Table 1 Item factor loadings of
the SCT scale
Factor loadings < 0.25 are not
reported
a
Factor 1: Sleepy/Sluggish;
Factor 2: Slow/Daydreamy;
Factor 3: Low Initiation/
Persistence
Item Factor
a
123
Seems drowsy 0.957
Appears tired; lethargic 0.871
Appears to be sluggish 0.845
Has a yawning, stretching, sleepy-eyed appearance 0.833
Is underactive, slow moving, or lacks energy 0.777
Is apathetic; shows little interest in things or activities 0.468 0.463
Seems to be in a world of his or her own 0.864
Gets lost in his or her own thoughts 0.846
Daydreams 0.724
Is slow or delayed in completing tasks 0.660
Needs extra time for assignments 0.495
Effort on tasks fades quickly 0.842
Lacks initiative to complete work 0.778
Is unmotivated 0.738
J Abnorm Child Psychol
Page 5
entirely consistent with those obtained in the pr ior EFA
using Principal Axis Factoring. Thus, in this case, the 3-
factor solution provides a reasonable solution for these data,
with clinically meaningful and robust factors.
Supplementary analyses examining the factor structure for
only those children within the elementary school age (e.g.,
between ages 5 and 11 years, inclusive) revealed no substan-
tial differences. The three factors remained consistent with
those presented in Table 1, with one exception. The is apa-
thetic item, which previously showed a sizeable cross-
loading on both factors 1 and 3, loaded more strongly on
factor 3 (0.56) in the elementary group, although it continued
to load on factor 1 as well (0.37). Thus, comparisons within
pre-pubertal children do not suggest a substantively different
structure to the SCT scale as compared with the total sample.
SCT Scale Total and ADHD Symptoms
Initial analyses examined associations between SCT and age
and gender; in this sample, age was not significantly correlat-
ed with total SCT scores (r0 0.08, p0 0.358). There was also
no association between SCT total score and child gender
(t
(141)
0 0.38, p0 0.704). SCT total scores were compared
across the four groups defined by ADHD Rating Scale-IV
symptom counts (i.e., low levels of behavioral symptomatol-
ogy and those with patterns of specific symptom character-
istics: high-I, high-H/I, and high-C). Examining ANOVA
results, there was a significant main effect of group [F
(3,139) 028.86, p< 0.001, η
p
2
0 0.3 8]. Post-hoc tests (i.e.,
Scheffe) revealed significant differences between the low-
symptoms group and children in both the high-I (p<0.001)
and high-C (p0 0.002) groups, with both symptomatic groups
rated as exhibiting higher levels of SCT symptomatology than
the low-symptoms group. In contrast, children in the high-H/I
group were not significantly different from the low-symptoms
group on teacher SCT ratings. Furthermore, quantifying
ADHD-related symptoms dimensi onally, the overall composite
SCT score was significantly (p <0.001) more strongly
associated with teacher reports of inattentive symptoms than
with hyperactive/impulsive symptoms, as measured by the
Inattentio n scale ( r0 0.75, p<0.001) and the Hyperactive/Im-
pulsive scale (r0 0.14, p0 0.096) totals from the ADHD Rating
Scale-IV (see Table 2).
SCT Factors and ADHD Symptoms
The associations among the three extracted SCT factors and
ratings of ADHD symptoms were also examined. Fishers r-
to-z transform ations were then used to examine differences
in the magnitude of the correlations between the SCT factors
and Inattention and Hyperactive/Impulsive subscale totals
from the ADHD Rating Scale-IV. Using this method, each
of the three SCT factors was significantly more strongly
correlated (all p<0.05) with inattentive symptoms than with
hyperactive/impulsive symptoms (see Table 2). In particular,
the Low Initiation/Persistence (r 0 0.82) and Slow/ Day-
dre amy (r0 0.72) factors w ere more strongly correlated
(p<0.001) with inattentive symptoms than the Sleepy/Slug-
gish factor (r0 0.46, p<0.001). Of note, the Low Initiation/
Persistence factor was the only SCT subscale which was
also significantly correlated with hyperactive/impulsive
symptoms (r0 0.29, p<0.001).
Linear regression analysis was used to predict teacher
ratings of SCT from ratings o f ADHD symptomatology.
Teacher ratings of inattentive and hyperactive/impulsive
symptoms (e.g., continuous ADHD Rating Scale-IV Inat-
tention and Hyperactivity/Impulsivity subscale totals) were
entered simultaneously in the analysis. Together, these
symptoms accounted for a significant proportion of the
variance in total SCT scores (R
2
0 0.62, p<0.001), with the
inattentive symptom s accounting for more than twice the
amount of variance (β0 0.89, p<0.001) than the hyperactive
symptoms (β0 0.29, p<0.001).
To further examine specificity of SCT symptoms and
separability of SCT characteristics from symptoms of
ADHD, SCT items and items from the ADHD Rating
Table 2 Correlations between SCT, ADHD symptomatology, and affective symptomatology
F1 F2 F3 IA HI Anx Depr
F1: Sleepy/Sluggish 0.591
**
0.558
**
0.455
**
0.009 0.082 0.235
**
F2: Slow/Daydreamy 0.681
**
0.723
**
0.152 0.157 0.175
F3: Low Initiation/Persistence 0.818
**
0.293
**
0.127 0.217
**
IA Total 0.483
**
0.119 0.179
*
HI Total 0.042 0.215
**
Anx Total 0.589
**
SCT Sluggish Cognitive Tempo; F1 Sleepy/Sluggish; F2 Slow/Daydreamy; F3 Low Initiation/Persistence; IA ADHD Rating Scale-IV Inattentive
Total; HI ADHD Rating Scale-IV Hyperactive/Impulsive Total; Anx Total Total Anxiety score from Vanderbilt Teacher Rating Scale; Depr Total
Depression score from Vanderbilt Teacher Rating Scale
*p0.05, **p0.01
J Abnorm Child Psychol
Page 6
Scale-IV were together subjected to an exploratory factor
analysis. Using principal axis factoring, with Promax rotation,
this additional analysis revealed four factors, explaining
64.00 % of the variance (see Table 3). The first factor, explain-
ing 36.29 % of the variance, was uniquely comprised of those
items assessing characteristics of hyperactivity/impulsivity
(e.g., interrupts, has difficulty awaiting turn). The third factor
explained an a dditional 5.69 % of the varia nce a nd was
comprised only of items from the Slow/Sluggish SCT factor,
without overlap from hyperactive/impulsive or inattentive
behavior items. The second and fourth factors (explaining
18.09 and 3.93 % of the variance, respectively) were com-
prised of items from both the SCT scale and the inattentive
items from the ADHD Rating Scale-IV. Specif ically, the
second factor contained all of the Low Initiation/Persistence
items from the SCT scale along with those items assessing
characteristics of the inattentive ADHD subtype that pertain to
task completion and persistence (e.g., avoids sustained effort,
fails to finish work, difficulty sustaining attention). The fourth
factor likewise contained all of the Slow/Daydreamy items as
well as those characteristics of ADHD which relate to forget-
fulness and distractibility (e.g., is forgetful, is easily distracted,
loses things).
SCT and Inter nalizing Symptoms
We further examined the associations between the SCT scale
total score and teacher-reported symptoms of anxiety and
Table 3 Factor loadings of the
SCT scale and ADHD rating
scale-IV items
a
Factor loadings < 0.25 are not
reported. HI Item from ADHD
Rating Scale-IV Hyperactivity/
Impulsivity items; IA Item
from ADHD Rating Scale-IV
Inattentive items; SCT Item from
Sluggish Cognitive Tempo scale
Item Factor
a
1234
HI Interrupts 0.906
HI Difficulty awaiting turn 0.858
HI Blurts out 0.822
HI Difficulty playing quietly 0.776
HI On the go 0.746
HI Talks excessively 0.720
HI Runs/climbs excessively 0.690
HI Leaves seat 0.647 0.291
HI Fidgets or squirms 0.481
SCT Effort on tasks fades quickly 0.958
IA Avoids sustained effort 0.919
IA Makes careless mistakes 0.752
SCT Is unmotivated 0.722
SCT Lacks initiative to complete work 0.698
IA Fails to finish work 0.633 0.252
IA Difficulty sustaining attention 0.557
IA Difficulty organizing 0.452 0.360
SCT Seems drowsy 0.906
SCT Yawning, sleepy-eyed appearance 0.875
SCT Appears to be sluggish 0.845
SCT Appears tired; lethargic 0.823
SCT Is underactive, slow moving, or lacks energy 0.763
SCT Is apathetic; shows little interest 0.385 0.540
SCT Seems to be in own world 0.942
SCT Gets lost in own thoughts 0.884
SCT Daydreams 0.838
SCT Is slow or delayed in completing tasks 0.263 0.668
IA Forgetful 0.618
SCT Needs extra time for assignments 0.370 0.313 0.501
IA Easily distracted 0.354 0.335 0.470
IA Does not listen 0.403 0.408
IA Loses things 0.354
J Abnorm Child Psychol
Page 7
depression, as rated on the Vanderbilt Rating Scale. Using a
conservative threshold for significance (p0.01), given mul-
tiple comparisons conducted, the SCT total score was signif-
icantly, but weakly, correlated with ratings of depressive
symptomatology (r0 0.24, p0 0.003) but not with ratings of
anxiety (r0 0.15, p0 0.079). Examining the pattern of associ-
ations between these estimates of internalizing symptomatol-
ogy and the SCT factors, there was a clear pattern of weak, but
specific correlations: the Sleepy/Sluggish and Low Initiation/
Persistence factors were significantly correlated with ratings
of depressive symptomatology (r0 0.24, p0 0.005 and r0 0.22,
p0 0.009, respectively), but not with ratings of anxiety
(r0 0.08, p0 0.333 and r0 0.13, p0 0.131, respectively).
SCT Factors and Impairment Ratings
Hierarchical linear regression analyses were performed to de-
termine the degree to which symptoms of SCT contribute to
childrens functional academic impairment, perceived impact
on classroom functioning, and childrens self-esteem, as rated
by teachers on the Impairment Rating Scale. Teacher ratings of
inattentive symptoms (ADHD Rating Scale-IV Inattention
scale total) were entered on the first step, followed by the three
SCT factor scores (Sleepy/Sluggish, Slow/Daydreamy, and
Low Initiation/Persistence) entered simultaneously on the sec-
ond step. After controlling for inattentive symptoms, the three
SCT factors together accounted for a significant proportion of
unique variance in impairment in academic progress (ΔR
2
0
0.06, p0 0.009; total model R
2
0 0.31). In particular, the Low
Initiation/Persistence factor (β0 0.41, p0 0.003) accounted for
the largest proportion of the variance in teacher ratings of
childrens reported academic impairment. Conversely, after
controlling for inattentive symptoms, the three SCT factors
did not add significantly to predictions of teacher ratings
regarding childrens behavioral impact upon the classroom
(ΔR
2
0 0.04, p0 0.092). Similarly, after controlling for inatten-
tive symptoms, the SCT factors did not predict childrens
impairment in self-esteem, as rated by their teachers (ΔR
2
0
0.03, p0 0.205). When ratings of depressive symptoms were
added into the regression (on the second step, following inat-
tentive symptom totals), the SCT factors remained significant
predictors of impairment in academic progress (ΔR
2
0 0.06, p0
0.009). As might be expected, while SCT symptoms did not
significantly predict teacher ratings of impairment in child self-
esteem, ratings of depressive symptoms did predict teacher
rated impairment in self-esteem (ΔR
2
0 0.27, p<0.001).
Discussion
Although there is a growing body of work examining con-
tributions of SCT to childrens outcomes, few studies have
examined the construct of SCT in depth (e.g., using more
than a few items), within a clinical sample, and via teacher
ratings of childrens behavior. The present study examined
the psychometric characteristics of a recently developed
measure of SCT (Penny et al. 2009) within a sample of
children referred for neuropsychological evaluation in the
United States. The SCT scale showed excellent internal
consistency within this sample (using teacher ratings) and
exploratory fa ctor ana lysis su ggest ed ex tract ion of t hree
primary factors from the s cale, which we have labeled
Sleepy/Sluggish , Slow/Daydreamy,andLow Initiation/
Persistence.
The three factors obtained from teacher ratings in this
clinical sample differed slightly from the two factors
extracted from teacher ratings in the original, non-clinical
sample (Penny e t al. 2009), which the authors labeled Slow
and Sleepy/Daydreamer. The three factors obtained in the
current sample appear to be somewhat more distinct in this
clinical population, with greatly reduced cross loadings, as
compared to the factors obtained in the original, non-clinical
sample. The wider range, increased variability, and greater
intensity of ADHD-related symptomatology evid ent in a
referred sample make more it likely that an increasingly
distinct factor structure (e.g., three factors) would be evident
within a referred sample. With regard to the correspondence
between the current three-factor structure and the original
two-factor solution, all of the items which loaded on our
Sleepy/Sluggish factor appeared to be drawn from the larger
Sleepy/Daydreamer factor in the original sample, with our
factor more specific to a sleepy or lethargic presentation.
Two additional items drawn from the original Sleepy/Day-
dreamer factor (e.g., daydreams, seems to be in a world of
his or her own) clearly loaded on a different factor in the
present analysis, the Daydreamy factor. Similarly, all of the
items which loaded on our Low Initiation/Persistence factor
appeared to have been drawn from the original Slow factor;
the three remaining items on the original Slow factor loaded
together onto our Daydreamy factor. Although three items
shared quite high cross loadings with both factors in the
original two-factor solution of teacher reported behavior
(e.g., is apathetic, is unmotivated, gets lost in his or her
own thoughts), in the present analysis those items loaded
more cleanly on two different factors, with the first two
items loading on our Low Initiation/Persistence factor and
the third loadi ng onto our Slow/Daydreamy factor.
Notably, the three-factor solut ion identified in the present
analysis is quite consistent with the three-factor solution
obtained fr om parent reports of behavior in the original,
non-clinical population. Our Sleepy/Sluggish factor is com-
prised of exactly the items that loaded on the second factor
in the original analysis of parent reported behaviors, which
the authors labeled Sleepy. All of t he items on our Low
Initiation/ Persistence factor are drawn from items wh ich
loaded onto the original parent reported Slow factor, with
J Abnorm Child Psychol
Page 8
the exception of two additional items which are more clearly
related to speed of task completion (e.g., is slow or delayed
in completing tasks, needs extra time for assignments). In
our analyses, these two specific items loaded together with
the three items that were originally part of the Daydreamer
factor onto our Slow/Daydreamy factor.
It is notable that the motivational or effort-based items
loaded together in teacher ratings of clinically-referred chil-
dren, resulting in a Low Initiation/Persistence factor in the
present sample, given that children with neurodevelopmen-
tal disabilities are at higher risk of being perceived as
putting forth less effort than their typically developing peers.
Alternatively, it may be that children who are perceived as
less motivated or giving less effort are more likely to strug-
gle academically or have co-occurring learning difficulties
and be referred for evaluation, especially an outside evalu-
ation (e.g., at a hospital outpatient clinic) rather than a
school-based evaluation. Additionally, the Low Initiation/
Persistence factor appears to be associated with ADHD-
related symptomatology more broadl y and is significantly
correlated with both inattentive and hyperactive/impulsive
behaviors. The Low Initiation/Persistence factor also was
the primary factor contributing significantly to prediction of
academic difficulties within the classroom setting. Given the
co-occurring learning difficulties common to children with
ADHD, especially in those referred for clinical evaluation, it
is not surprising that the factor that may best reflect a pattern
of withheld or reduced effort in the face of frustration is
most correlated with teacher reports of academic impair-
ment. Conversely, the Sleepy/Sluggish factor was least pre-
dictive of academic impairment ratings, but the factor most
significantly (albeit weakly) correlated with internalizi ng
(e.g., depressive) symptoms. Taken together, these findings
suggest that this factor might be qualitatively different from
cognitive slowness/processing speed in general; the behav-
ioral characteristics described by items loading on the
Sleepy/Sluggish factor (drowsiness, lethargy, etc.) may con-
tribute in a different way to functional impairment.
Previous work has yielded differing findings regarding the
relation between SCT and inattentive symptoms. Hartman and
colleagues (2004) found that SCT and inattention are separa-
ble constructs representing distinct factors, while others have
not found this distinction (e.g., Todd et al. 2004). Our data
appear to further support the specificity of the SCT construct,
particularly those items pertaining to sluggishness, lethargy,
and underactivity. Aspects of SCT that reflect poor initiation,
impersistence, and a tendency to daydream appear to be less
distinct and show more overlap with inattentive symptoms of
ADHD.
With regard t o psy chometric properties of the scale,
Penny et al. (2009) reported sizable cross loadings between
the factors on teacher ratings. The authors noted that three
items (e.g., is apathetic, is unmotivated, gets lost in his or
her own thoughts) loaded equally well on both factors found
in the original study. This pattern was not observed in the
current study, in which only one of those items (is apathetic)
showed a pattern of significant cross-loading on both the
Sleepy/Sluggish and Low Initiation/Persistence factors. Over-
all, there were few significant cross loadings for items on the
SCT scale in this sample.
In summary, preliminary construct validity of the Penny
SCT scale in a clinical sample was established via a pattern
of stronger associations between SCT symptomatology and
ratings of inattention and distractibility than hyperactivity
and impulsivity on the ADHD Rating Scale-IV. These find-
ings are con sistent w ith sim ilar fin dings of a sso ciatio ns
between SCT symptomatolo gy and inattention using the
SCT scale of the CBCL conducted by Hartman et al.
(2004) and Garner et al. (2010). Additionally, symptoms
of SCT uniquely predicted impairment in childrens aca-
demic progress, even after accounting for their level of
inattentive symptomatology. These findings add to a grow-
ing body of research that suggests that sluggish cognitive
tempo is not entirely explained by DSM-IV defined inatten-
tion. This unique constellation of symptomatology, particu-
larly that reflected in the Low Initiation/Persistence factor,
may correspond to the impersistence, especially motor
impersistence, frequently seen in children with ADHD
(Mahone et al.
2006).
Future work should examine the
associ
ation between SCT, particularly that aspect measured
by the Low Initiation/Persistence factor, and measures of
motor persistence in children with ADHD.
These results suggest that measurement of SCT can help
to better characterize the symptomatology seen in children
with ADHD. Although previous work has suggested that
SCT shares symptom overlap with anxiety or other internal-
izing behaviors, recent work (Murphy-Bowman et al. 2011)
has shown a degree of dissociation between ratings of SCT
and informant ratings of anxiety. Data from the current
sample also suggest only weak associations between
teacher-reported SCT symptoms and teacher-reported symp-
toms of depression or anxiety. As such, behaviors charac-
teristic of SCT are not clearly defined by inattentive
symptomatology alone, nor are they clearly accounted for
by internalizing behaviors. Since SCT symptomatology
accounts for significant variance in childrens performance
on measures of processing speed, some portion of the SCT
construct may be best explained by overall speed of cogni-
tive response preparation.
Finally, given current discussions surrounding changes in
ADHD diagnostic criteria for the upcoming revision of DSM-
IV (A PA 2010), and potential inclusion of a restricted-
Inattentive subtype, reliable and validated measures of SCT
will be necessary to better assess characteristics of the con-
struct, especially within this restricted Inattentive subtype of
ADHD. Careful measurement of SCT may also help to better
J Abnorm Child Psychol
Page 9
predict outcomes for these children, and ultimately, identify
those children most likely to benefit from specific types of
interventions.
Although the present findings provide an important initial
step in detailed measurement of the SCT construct within a
clinically-referred sample, there were several limitations in
the current study. Most notably, data were collected from
children referred to an outpatient neuropsychology evalua-
tion servi ce and as a result, typically developing children
were not in cluded as a control group against whic h the
pattern seen in clinic-referred children can be compared. In
this sample, almost two -thirds of those w ith a relatively
elevated level of ADHD-related symptomatology demon-
strated primarily inattentive symptoms; results therefore
may not generalize to samples comprised of children with
primarily hyperactive-impulsive presentations. However, it
is notable that recent data suggest that approximately twice
as many American school-aged children are diagnosed with
the predominantly inattentive subtype of ADHD (4.3 %)
compared to the hyperactive -impulsive (2.0 %) or combined
subtypes (2.2 %) (Froehlich et al. 2007; Merikangas et al.
2010). Therefore, our sample approximates the relative
prevalence of the different symptom presentations in chil-
dren in this country.
Additionally, measures of SCT, ADHD-related symptom-
atology, and ratings of academic impairment were all com-
pleted by childrens teachers, thus results may be confounded
by similar methodology and raters. Teacher ratings were not
available for every child referred for neuropsychological eval-
uation, as obtaining such pre-visit information depends upon
both parent and teacher willingness and time constraints.
Notably, there might have been differences in demographic
characteristics between those children for whom ratings were
obtained and those without these teacher ratings; we could
speculate that children for whom such pre-visit data are avail-
able may come from homes with parents who have better
organizational capabilities for managing pre-visit paperwork
and scheduling or who may have higher levels of educational
attainment. This might suggest that their children, also, may
be apt to demonstrate less severe clinical symptomatology
with regard to inattention, impulsivity, and/or SCT. As a
result, this bias could limit the size of effects seen in our
findings, suggesting potentially larger associations in a more
heterogeneous sample. Similarly, children for whom such
ratings are available may be more likely to also have teachers
who are more likely to have time to complete such ratings,
have the organizational and time management skills to do so,
and feel invested in their students. These teachers may be less
likely to teach students within impoverished, inner-city
schools; thus, potential teacher bias may also suggest that
our finding may represent an underestimate of effects. Fur-
thermore, given the pattern of weak correlations observed
between parents and teachers in children's behavioral ratings
(e.g., Achenbach et al. 1987), future work should examine
correspondence between teacher and parent ratings on this
measure in a clinical sample. It will also be important for
future studies to examine specific associations between teach-
er and parent ratings of SCT and performance-based measures
of childrens attentional regulation, processing speed, and
response time, in order to better validate this scale as a mea-
sure of the SCT construct.
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    • "Lastly, our hypothesis that SCT would be negatively associated with ODD symptoms after controlling for inattention/hyperactivity and other psychopathology symptoms was supported. Several studies have now found that, when controlling for ADHD, SCT is associated with fewer externalizing behaviors (Becker et al., 2014a; Bernad et al., 2014 Bernad et al., , 2015 Jacobson et al., 2012; Lee et al., 2014). Our ability to replicate this finding in a clinical sample of sleep-disordered children provides important support for the likely generalizability of this finding across sample types. "
    [Show abstract] [Hide abstract] ABSTRACT: Research supports the distinctness of sluggish cognitive tempo (SCT) (e.g., mental confusion and slowed behavior/thinking) from other psychopathologies. However, the relation between SCT and sleep functioning has not been adequately studied. We examined the association between SCT and sleep functioning in 325 children (62% male) ages 6-10 years referred to a pulmonary-based, accredited Sleep Disorders Center. Correlations between caregiver ratings of SCT, other psychopathologies (i.e., inattention/hyperactivity, oppositionality, depression, anxiety), sleep functioning (both behavioral and organic symptoms), as well as sleep disorder diagnoses, were examined. Unique effects of SCT and other psychopathologies on sleep problem severity controlling for child demographics were assessed using regressions. Regression analyses were also conducted to examine the unique effects of SCT on impairment (i.e., academic difficulties, parenting stress, and other psychopathologies) controlling for child demographics, sleep problem severity, and other psychopathology symptoms. SCT was weakly to moderately correlated with most measures of sleep (rs=.07-.39) and moderately to strongly correlated with measures of daytime sleepiness (rs=.33 and .53). SCT was uniquely associated with greater sleep functioning severity and impairment in academic functioning. SCT was also uniquely associated with higher levels of depression and inattention/hyperactivity, but not anxiety, and negatively associated with oppositionality. Finally, SCT symptoms were uniquely associated with greater parent-child dysfunctional interaction. Findings demonstrate that SCT is related to, but not redundant with, sleep problems and daytime sleepiness specifically. Further, SCT remained associated with several domains of functional impairment in sleep-disordered children after controlling for clinically-relevant variables, highlighting the potential value in assessing SCT symptoms in children with sleep problems.
    No preview · Article · Mar 2016 · Journal of Psychiatric Research
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    • "than anxiety (r = .55) is in line with other studies showing SCT to be more strongly related to depression than to anxiety (Barkley, 2013; Cortés et al., 2014; Jacobson et al., 2012). Taken together, these findings provide initial evidence of the CCI's construct validity, with CCI scores most strongly associated with ADHD inattention and internalizing symptoms (and child-rated depression in particular). "
    [Show abstract] [Hide abstract] ABSTRACT: Sluggish cognitive tempo (SCT) is characterized by excessive daydreaming, mental confusion, slowness, and low motivation. Several teacher- and parent-report measures of SCT have recently been developed but a child self-report measure of SCT does not yet exist despite clear links between SCT and internalizing psychopathology (for which self-report is often desired). This study examined the initial reliability and validity of the Child Concentration Inventory (CCI), a child self-report measure of SCT symptoms, in a school-based sample of 124 children (ages 8-13; 55% female). Children completed the CCI and measures of academic/social functioning, emotion regulation, and self-esteem. Teachers completed measures of psychopathology symptoms (including SCT) and academic/social functioning. Although exploratory structural equation modeling (ESEM) supported a three-factor model of the CCI (consisting of Slow, Sleepy, and Daydreamer scales closely resembling the factor structure of the parent-report version of this measure), bifactor modeling and omega reliability indices indicated that the CCI is best conceptualized as unidimensional. CCI scores were significantly correlated with teacher-rated SCT and were statistically distinct from teacher-rated ADHD and child-rated anxiety/depression. After controlling for sex, grade, and other psychopathology symptoms, the CCI total score was significantly associated with poorer child-reported academic/social functioning and self-worth in addition to increased loneliness and emotion dysregulation. Child ratings on the CCI were moderately-to-strongly correlated with poorer teacher-rated academic/social functioning but these associations were reduced to nonsignificance after controlling for demographics and other psychopathology symptoms. Findings provide preliminary support for the CCI, and future directions include replication with adolescents and clinical samples in order to further examine the CCI’s factor structure, reliability, validity, and clinical utility.
    Full-text · Article · Dec 2014 · Psychological Assessment
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    • "It is not surprising that Jessica displays ADHD symptoms in addition to SCT, since it is estimated that 60% of children with elevated SCT also display significant ADHD symptoms (Barkley, 2013). In addition to the co-occurrence of SCT and ADHD, multiple studies show SCT to be associated with internalizing symptoms broadly ( Becker, Luebbe, Fite, et al., 2014; Garner et al., 2010; Jacobson et al., 2012; Penny et al., 2009), and depression in particular (Barkley, 2013; Becker, Luebbe, Fite, et al., 2014; Bernad et al., 2014; Cortés et al., 2014; Jacobson et al., 2012). In the case of Jessica, her parents' ratings on the CBCL resulted in elevations on the broadband internalizing scale and anxious/depressed syndrome scale, but her parents did not endorse any clinically significant anxious or depressive symptoms on the K-SADS. "
    [Show abstract] [Hide abstract] ABSTRACT: Despite the burgeoning scientific literature examining the sluggish cognitive tempo (SCT) construct, very little is known about the clinical presentation of SCT. In clinical cases where SCT is suspected, it is critical to carefully assess not only for attention-deficit/hyperactivity disorder (ADHD) but also for other comorbidities that may account for the SCT-related behaviors, especially internalizing symptoms and sleep problems. The current case study provides a clinical description of SCT in a 7-year-old girl, offering a real-life portrait of SCT while also providing an opportunity to qualitatively differentiate between SCT and attention-deficit/hyperactivity disorder (ADHD), other psychopathologies (e.g., depression, anxiety), and potentially related domains of functioning (e.g., sleep, executive functioning). “Jessica” was described by herself, parents, and teacher as being much slower than her peers in completing schoolwork, despite standardized testing showing Jessica to have above average intelligence and academic achievement. Jessica’s parents completed rating scales indicating high levels of SCT symptoms and daytime sleepiness, as well as mildly elevated EF deficits. More research is needed to determine how to best conceptualize, assess, and treat SCT, and Jessica’s case underscores the importance of further work in this area.
    Full-text · Article · Sep 2014 · Clinical Child Psychology and Psychiatry
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