Journal of Abnormal Child Psychology, Vol. 26, No. 4, 1998, pp 257-268
The Revised Conners' Parent Rating Scale (CPRS-R):
Factor Structure, Reliability, and Criterion Validity
C. Keith Conners,1,4 Gill Sitarenios,2 James D. A. Parker,3 and Jeffery N. Epstein1
Received June 19, 1997; accepted September 8, 1997
The Conners' Parent Rating Scale (CPRS) is a popular research and clinical tool for obtaining parental reports of childhood behavior problems. The present study introduces a
revised CPRS (CPRS-R) which has norms derived from a large, representative sample of
North American children, uses confirmatory factor analysis to develop a definitive factor
structure, and has an updated item content to reflect recent knowledge and developments
concerning childhood behavior problems. Exploratory and confirmatory factor-analytic results
revealed a seven-factor model including the following factors: Cognitive Problems, Oppositional, Hyperactivity-Impulsivity, Anxious-Shy, Perfectionism, Social Problems, and Psychosomatic. The psychometric properties of the revised scale appear adequate as demonstrated
by good internal reliability coefficients, high test-retest reliability, and effective discriminatory
power. Advantages of the CPRS-R include a corresponding factor structure with the Conners' Teacher Rating Scale—Revised and comprehensive symptom coverage for attention
deficit hyperactivity disorder (ADHD) and related disorders. Factor congruence with the
original CPRS as well as similarities with other parent rating scales are discussed.
KEY WORDS: ADHD; CPRS-R; rating scale; parents; childhood.
The initial Conners' Parent Rating Scale (CPRS)
was developed as a comprehensive checklist for acquiring parental reports of the basic presenting problems for children referred to an outpatient psychiatric
setting (Conners, 1970). This scale was used to form
the basis for a detailed parental interview about the
child's problems. In its original form, the CPRS contained items grouped in terms of problems with sleep,
problems eating, problems with temper, problems
with keeping friends, problems in school, etc. Later,
an "additional" problems category was added that included items covering the cardinal symptoms of attention deficit hyperactivity disorder (ADHD): hyperactivity, impulsivity, and inattention.
Since its introduction (Conners, 1970), the psychometric properties of the CPRS have been well
studied. The original scoring procedure required
grouping of items according to rationally derived
problem groups. Though this scoring procedure was
face valid, it was not until a series of factor-analytic
studies of the CPRS were conducted (Blouin, Conners, Seidel, & Blouin, 1989; Conners, 1970, 1973)
that an empirical scoring methodology was employed. These factor analyses of the CPRS (Blouin
et al., 1989; Conners, 1970) utilized 316 clinic patients and 367 normal controls whose parents were
recruited from Baltimore-area public schools. Using
the 93 CPRS items as the unit of analysis, eight factors were identified: Conduct Disorder, Anxious-Shy,
Restless-Disorganized, Learning Problems, Psychosomatic, Obsessive-Compulsive, Antisocial, and Hyperactive-Immature. The factor structure and norms
from this sample have been used for scoring the 93item CPRS (Conners, 1989).
With time, the CPRS has developed into a
popular instrument for screening and assessing behavior problems and has become a useful and effective parent rating scale for assessing psychosocial
(e.g., Horn, lalongo, Popovich, & Peradotto, 1987)
1Duke University Medical Center, Durham, North Carolina 27710.
University, Toronto, Ontario, Canada, M3J-1P3.
3Trent University, Peterborough, Ontario, Canada K9J-7B8.
4Address all correspondence concerning this article to C. Keith
Conners, Box 3431, Duke University Medical Center, Durham,
North Carolina 27710.
2York
257
0091-0627/98/0800-0257$15.00/0 C 1998 Plenum Publishing Corporation
258
and drug treatment outcomes in children with disruptive behavior problems (e.g., Fischer & Newby,
1991). Several versions of the CPRS are currently in
use including a 48-item questionnaire resulting from
a restandardization of a subset from the original
scale (Goyette, Conners, & Ulrich, 1978). A 10-item
abbreviated questionnaire was also constructed from
the items with the best factor loadings (Conners,
1994).
Some factor analytic research with the CPRS
and its related scales on clinical samples have suggested slightly differing CPRS factor structures (Cohen, DuRant, & Cook, 1988; O'Connor, Foch,
Sherry, & Plomin, 1980) than was reported originally.
For example, Cohen (Cohen et al., 1988) found that
Learning Problems did not form a separate factor in
his clinic sample but instead loaded on the Impulsive-Hyperactive factor, thereby forming an overall
ADHD factor. Cohen argued that this factor structure was consistent with some investigators contentions that attention (Learning Problems) and hyperactivity (Impulsivity-Hyperactivity) tend to present as
a single disorder in clinical populations (Cohen &
Hynd, 1986; Werry, Sprague, & Cohen, 1975).
Despite some differences in factor structure
across studies, the psychometric properties of the
CPRS have made this scale an attractive research
and clinical tool. Good reliability of the CPRS as assessed by test-retest (Glow, Glow, & Rump, 1982)
and interrater reliability (Conners, 1973) has been
established. In addition, the CPRS's concurrent validity is well established by high correlations with
similar factors on other parent rating scales, such as
the Child Behavior Checklist (Achenbach & Edelbrock, 1983; Mash & Johnston, 1983) and Behavior
Problem Checklist (Arnold, Barnebey, & Smeltzer,
1981; Campbell & Steinert, 1978). Further evidence
of its validity comes from research demonstrating the
discriminatory power of the CPRS in differentiating
behaviorally disordered children from normal children (Prior & Wood, 1983; Ross & Ross, 1976, 1982)
and between differing types of behavioral disorders
(Conners, 1970; Kuehne, Kehle, & McMahon, 1987;
Leon, Kendall, & Garber, 1980).
Though the CPRS continues to experience widespread use by both clinicians and researchers, several
issues indicate that an update and restandardization
of the CPRS is necessary. First, current norms for
the CPRS are based on normative data from a relatively small sample of Baltimore-area school children
gathered in the 1960s. The size, geographical representation, and demographics of this sample are prob-
Conners, Sitarenios, Parker and Epstein
ably not representative of the wide range of children
for whom the CPRS is applied today. Second, as discussed above, the factor structure of the CPRS has
varied across studies. No studies to date have ever
tested and confirmed the CPRS factor structure using cross-validation, replication, or confirmatory factor analysis. Therefore, a definitive factor structure
has not been established.
Third, the original item content was developed
to provide a comprehensive and broad assessment of
childhood behaviors, including feeding, eating, and
sleeping problems among others. But many of these
items are unrelated to the most common behavior
problems typically encountered. The scale has also
been criticized for lacking sufficient emphasis on internalizing states such as anxiety and depression. Extensive use has shown that a briefer and more focused
scale would be useful. Scale brevity and focus is relevant for ease of use and increasing parent compliance.
This becomes increasingly important when repeated
administration is necessary (i.e., when monitoring behavioral or pharmacologic interventions ).
Last, item content of the CPRS has not been
updated to reflect the accumulating body of knowledge about behavior disorders. The original item
content was reflective of conceptualizations of behavioral problems during the 1960s-1970's. Some
ADHD-related behaviors (e.g., academic problems)
and ADHD symptoms (e.g. excessive talking) were
not included because neither well-developed ADHD
criteria nor information about comorbid disorders
were available at the time of scale development.
Thus, the goal of the present study was to revise
the CPRS by (1) deriving norms using a large, representative sample of North American children; (2)
using confirmatory factor analysis to develop a definitive factor structure; (3) focusing the revised scales
on behaviors that are directly related to ADHD and
its associated behaviors; and (4) updating the item
content to reflect recent knowledge and developments concerning ADHD. In addition, the reliability
and validity of this revised scale was examined.
STUDY 1: SCALE DEVELOPMENT
Method
Subjects
Subjects consisted of 2,200 students (1,099 males
and 1,101 females) ranging in age from 3 to 17 years.
259
Revised Conners' Parent Rating Scale
Females had a mean age of 10.43 years (SD = 3.73)
and males a mean age of 10.09 years (SD = 3.68).
The median annual household income of the students rated by their parents was between $40,001 and
$50,000. Eighty-four percent of the students were
European American, 5% African American, 4% Hispanic, and 7% other.
Procedure
Officials and school psychologists from approximately 200 schools throughout Canada and the
United States functioned as site coordinators for the
present study. Site coordinators were provided with
consent forms, questionnaires, and forms which outlined the background of the study to parents and
students in the school. Parent who agreed to participate were asked to rate as many of their schoolage children as possible. Children and adolescents
in special education classes were not included in this
study.
Many new items were created in order to
strengthen some of the weaker factors (e.g., internalizing behaviors) and those previously underrepresented. A preliminary item analysis on approximately 100 ratings was used to remove items with
restricted variance or comments regarding readability, interpretability, or vagueness. Parents were
asked to rate each item on the 193 item-pool using
4-point Likert scales (ranging from 0 for not at all
true to 3 for very much true). Completed forms were
returned to the site coordinators and forwarded to
the authors.
Statistical Analyses
The sample was randomly divided into a derivation sample (n = 1,100) and a replication sample
(n = 1,100). The 193 items from the derivation sample were intercorrelated and the resulting matrix subjected to principal axis factoring. A series of factor
analyses was conducted to determine what items
should be retained. Items were included on the final
version of the scale if the following criteria were met:
(1) Items had to load significantly (greater than .30)
on a given factor and lower than .30 on the other
factors, and (2) following the rational approach to
scale construction, an item was eliminated if it lacked
conceptual coherence with its factor. Scree test and
eigenvalues (> 1.0) were used to select the number
of factors for rotation (Cattell, 1978). In addition, we
employed the split-half factor comparabilities
method (Everett, 1983) to determine the most reliable factor solution.
The factor structure for the CPRS-R was tested
in the replication sample (n = 1,100) using confirmatory factor analysis with EQS for Windows (version 5.1; Bentler, 1995). As recommended by Cole
(1987) and Marsh, Balla, and McDonald (1988),
multiple criteria were used to assess the goodnessof-fit of the six-factor model: the goodness-of-fit index (GFI; Joreskog & Sorbom, 1986), the adjusted
GFI (AGFI; Joreskog & Sorbom, 1986), and the
root mean-square residual (RMS). Based on the recommendations of Anderson and Gerbing (1984),
Cole (1987), and Marsh et al. (1988), the following
criteria were used to indicate the goodness-of-fit of
the model to the data: GFI > .85; AGFI > .80;
RMS < .01.
Results
Scale Development
The correlation matrix of the 193 item-pool was
subjected to principal-axis factoring and scree test
and eigenvalue greater than 1.0 criteria (Cattell,
1978). These criteria indicated the relative suitability
of six, seven, and eight factors for rotation. In order
to determine the most reliable number of factors to
retain for rotation, the split-half factor comparabilities method was applied (Everett, 1983). To this end,
the derivation sample was randomly split into two
subsamples (n = 550 and 550). For each sample six-,
seven-, and eight-factor solutions were rotated to solution (varimax rotation). Results indicated that the
seven-factor solution produced the highest factor
comparability coefficients. Based on these results, the
entire derivation sample was factor-analyzed and
seven factors were rotated to a varimax solution.
Items were eliminated from further analyses because
they failed to load (above .30) on any one factor, or
because they loaded above .30 on more than one factor (in several cases items were retained that double-loaded above .30 because there was a high loading for the target factor and the loading for the
second factor was just above .30). The remaining
items were factor-analyzed and seven factors rotated
to a varimax solution. This procedure was repeated
until 57 items remained. Table I presents the factor
loadings, eigenvalues, and percentage of variance for
260
Conners, Sitarenios, Parker and Epstein
Table I. Rotated Factor Loadings from a Principal Axis Factor Analysis of Items from the Conners'
Parent Rating Scale— Revised (CPRS-R) (Derivation Sample, n = 1,100)
Factors
CPRS-R items
1
2
3
4
5
6
1
.047
.019
.106
.161
.100
.049
.153
-.022
.110
.100
.061
.073
.019
.027
-.013
.006
-.062
.033
-.047
-.050
-.008
-.105
-.021
.113
.048
.103
.111
.106
.144
.074
.099
.030
.082
.080
.110
.095
.078
.076
.057
.090
.073
.142
.080
.095
.069
.130
.121
.106
.049
.112
.089
.107
.069
.177
.109
.107
.148
.065
.057
.081
.087
.017
-.006
.117
.002
.055
-.015
.132
.049
.125
.075
.046
.117
.157
.093
.151
.112
.204
.117
.116
.161
.061
.120
.153
.072
.096
.052
.012
.135
.106
.174
.105
.130
.117
-.063
.138
.123
-.051
-.028
.072
.055
-.012
.023
.107
.112
.024
.024
.052
.126
.138
-.028
.219
.137
.120
.030
.019
-.006
.114
.056
.027
.003
.114
.094
.726
.710
.700
.626
.630
.521
.538
.481
.141
.105
.067
.032
.129
.144
.146
.061
.081
.114
.114
.004
.079
-.036
.179
.145
.116
.053
.079
.107
.190
.086
.034
.140
.117
.067
.099
.218
.151
-.053
.119
.740
.698
.570
.694
.632
.647
.612
.070
.039
-.054
.095
.075
.042
.052
.075
.056
-.023
.041
.029
.087
.052
(c.ontinued)
Factor 1: Cognitive Problems
Difficulty completing
Fails to complete
Needs supervision
Avoids mental effort
Trouble concentrating
Careless mistakes
Arithmetic problems
Sloppy handwriting
Fails to finish
Forgetful
Loses things
Poor spelling
.793
.760
.752
.737
.691
.686
.557
.604
.620
.600
.581
.545
Angry
Argues
Loses temper
Irritable
Defies adults
Annoy people
Touchy
Blames others
Spiteful
Fights
.161
.194
.195
.212
.213
.210
.162
.273
.190
.069
180
56
178
172
183
52
179
182
60
Always on the go
Hard to control
Runs excessively
Restless
Difficulty waiting
Run around at meals
Difficulty being quiet
Blurts out answers
Excitable
.192
.149
.170
.196
.228
.063
.225
.230
.259
95
90
89
91
94
170
138
156
Timid
Afraid of people
Afraid of new situations
Afraid of being alone
Many fears
Afraid of the dark
Shy
Clings to parents
.055
.051
.174
.048
.162
.015
.084
.111
114
117
116
85
78
81
112
111
84
87
175
110
.207
.232
.130
.280
.175
.209
.053
.119
.311
.294
.204
.024
.063
.135
.240
.230
.295
.184
.010
.074
.288
.269
.257
.064
007
Factor 2: Oppositional
48
43
42
20
44
45
47
46
24
4
.723
.638
.653
.648
.643
.611
.639
.575
.581
.471
.122
.187
.244
.187
.275
.200
.085
.173
.161
.181
Factor 3: Hyperactivity-Impulsivity
.121
.240
.190
.137
.275
.088
.284
.218
.294
.708
.708
.728
.637
.644
.577
.627
.506
.577
Factor 4: Anxious-Shy
.136
.165
.187
.037
.241
.055
.053
.037
.038
.027
.063
.193
.100
.205
-.033
.274
Factor 5: Perfectionism
130
133
135
131
137
132
136
Everything just so
Keeps checking
Fussy
Things done same way
Has rituals
Sets high goals
Upset if things moved
-.114
-.028
.036
.002
.052
-.148
.043
.078
-.029
-.024
.096
.112
-.066
.179
.072
.038
-.008
.148
.094
-.032
-.043
Revised Conners' Parent Rating Scale
261
Table I. (Continued)
Factors
CPRS-R items
1
2
3
4
5
6
7
.153
.046
.272
.070
.215
.048
.045
.102
.075
.096
.793
.725
.704
.636
.424
.012
.043
.029
.133
.162
.101
.144
.120
.032
.181
.161
.066
.095
.011
.098
-.024
.098
.011
.055
-.022
.125
.060
.110
.750
.616
.648
.452
.531
.306
Factor 6: Social Problems
140
143
142
147
144
No friends
Loses friends
Does not make friends
Doesn't get invited
Feels inferior
.162
.203
.197
.137
.242
123
124
125
122
128
126.
Stomach aches
Aches and pains
Aches before school
Headaches
Complains
Seems tired
.083
.091
.166
.151
.144
.187
.164
.212
.142
.180
.211
.112
.192
.120
.115
-.004
Factor 7: Psychosomatic
Eigenvalues
% of Variance
14.67
25.7
.137
.154
.086
.129
.174
.243
.094
.032
.069
.002
.118
-.040
4.20
2.59
2.15
2.11
1.86
1.37
7.4
4.5
3.8
3.7
3.3
2.4
each factor for this analysis. The seven rotated factors accounted for 50.8% of the total variance. The
first factor accounted for 25.7% of the total variance
and the 12 items that loaded on this factor appeared
to tap a "cognitive problems" dimension. The second
factor accounted for 7.4% of the total variance and
the 10 items that loaded on this factor appeared to
tap an "oppositional" dimension. The third factor accounted for 4.5% of the total variance and the nine
items that loaded on this factor appeared to tap a
"hyperactivity-impulsivity" dimension. The fourth
factor accounted for 3.8% of the total variance and
the eight items that loaded on this factor appeared
to tap an "anxious/shy" dimension. The fifth factor
accounted for 3.7% of the total variance and the
seven items that loaded on this factor appeared to
tap a "perfectionism" dimension. The sixth factor accounted for 3.3% of the total variance and the five
items that loaded on this factor appeared to tap a
"social problems" dimension. The seventh factor accounted for 2.4% of the total variance and the six
items that loaded on this factor appeared to tap a
"psychosomatic" dimension.
and RMS = .0291).5 All of the parameter estimates
between items and factors were significant: For the
Oppositional Factor, the 10-parameter estimates
ranged from .603 to .792 (mean = .720); for the Cognitive Problems factor, the 12-parameter estimates
ranged from .529 to .866 (mean = .743); for the Hyperactivity-impulsivity factor, the nine-parameter estimates ranged from .610 to .791 (mean = .715); for
the Anxious/Shy factor, the eight-parameter estimates
ranged from .518 to .752 (mean = .644); for the Perfectionism factor, the seven-parameter estimates
ranged from .528 to .699 (mean = .643); for the Social Problems factor, the five-parameter estimates
ranged from .597 to .855 (mean = .767); for the Psychosomatic factor, the six-parameter estimates ranged
from .476 to .751 (mean = .632).
STUDY 2: RELIABILITY, INTERNAL
CONSISTENCY, AND AGE AND SEX
DIFFERENCES
Method
Participants
Factor Replication
The seven-factor oblique model for the 57-item
CPRS-R was tested using confirmatory factor analysis
on the cross-validation sample (n = 1,100). All three
goodness-of-fit indicators suggested that the model
had good fit to the data (GFI = .863, AGFI = .849,
The sample consisted of the 2,200 students used
in Study 1 (1,101 males and 1,099 females). A subset
5
The model had to be slightly modified with the addition of selected correlated errors (0.9% of possible correlated errors). See
Tanaka and Huba (1984) for a discussion of this procedure. The
mean for these error correlation was .244 (range = .134 to .399).
262
Conners, Sitarenios, Parker and Epstein
Table II. Internal Reliability Coefficients for Scales on the Conners' Parent Rating
Scale-Revised (CPRS-R)
3 to 7 years
8 to 12 years
13 to 17 years
Male
Female
Male
Female
Male
Female
Oppositional
Cognitive Problems
Hyperactivity-Impulsivity
Anxious/Shy
Perfectionism
Social Problems
Psychosomatic
.89
.92
.92
.86
.86
.85
.77
.88
.92
.91
.86
.88
.87
.83
.92
.94
.91
.85
.82
.88
.75
.91
.92
.83
.85
.83
.81
.79
.92
.93
.85
.81
.84
.87
.82
.90
.93
.75
.82
.82
.85
.75
n
307
286
479
467
315
346
CPRS-R Scale
tions: .60 (p < .05) for Oppositional, .78 (p < .05)
for Cognitive Problems, .71 (p < .05) for Hyperactivity-Impulsivity, .42 (p < .05) for Anxious/Shy, .60
(p < .05) for Perfectionism, .13 (p = n.s.) for Social
Problems, and .55 (p < .05) for Psychosomatic.
Means and standard deviations for the various
CPRS-R scales (separately by sex and age group) are
presented in Table III. A series of (Sex x Age Group)
analyses of variance were conducted with each of the
CPRS-R scales as the dependent variable. For the
Oppositional scale, males were rated significantly
higher than females [F(l, 2,194) = 14.55, p < .001],
but the main effect for age group and the interaction
were not significant.
For the Cognitive Problems scale, males were
rated significantly higher than females [F(l, 2,194) =
of 49 children (23 males and 26 females) were rated
by their parent on the CPRS-R on two occasions approximately 6 weeks apart.
Results
Table II presents the internal reliability coefficients for the CPRS-R scales, separately for 3- to 7year-olds, 8- to 12-year-olds, and 13- to 17-year-olds.
Coefficient alphas for the seven scales on the CPRSR ranged from .75 to .94 for males and .75 to .93
for females, suggesting that the scales on the CPRSR have excellent internal reliability. Using Pearson
product-moment correlations (n = 50), the CPRS-R
scales had the following 6-week test-retest correla-
Table III. Means and Standard Deviations for Scales on the Conners' Parent Rating Scale— Revised (CPRS-R)
3 to 7 years
CPRS-R Scale
Oppositional
Mean
SD
Cognitive Problems
Mean
SD
Hyperactivity-Impulsivity
Mean
SD
Anxious/Shy
Mean
SD
Perfectionism
Mean
SD
Social Problems
Psychosomatic
Total
13 to 17 years
Females
Males
Females
Males
Females
Males
Females
Males
4.89
(4.44)
5.61
(5.00)
4.59
(4.88)
5.89
(5.68)
4.82
(4.96)
5.37
(5.53)
4.74
(4.79)
5.66
(5.46)
3.84
(5.80)
5.93
(7.07)
4.14
(5.69)
8.33
(8.28)
4.87
(6.79)
8.31
(8.29)
4.29
(6.09)
7.65
(8.03)
3.60
(4.75)
4.83
(5.79)
1.54
(2.65)
3.18
(4.74)
1.26
(2.18)
1.93
(3.28)
1.99
(3.36)
3.28
(4.83)
4.78
(4.33)
4.19
(4.28)
2.71
(3.45)
2.89
(3.72)
2.12
(3.04)
1.50
(2.66)
3.06
(3.73)
2.85
(3.76)
3.97
(4.23)
3.42
(3.94)
3.73
(3.80)
3.36
(3.56)
4.52
(4.28)
4.15
(4.29)
4.04
(4.08)
3.60
(3.90)
.78
.86
.88
1.2
SD
(1.82)
(2.03)
(1.77)
(2.43)
11.0
(2.13)
11.0
(2.32)
8.89
(1.90)
1.07
(2.29)
Mean
1.60
(2.42)
1.24
(2.04)
1.55
(2.23)
1.62
(2.16)
1.92
(2.32)
1.58
(2.43)
1.68
(2.31)
1.50
(2.21)
286
307
467
479
346
315
1,099
1,101
Mean
SD
n
8 to 12 years
263
Revised Conners' Parent Rating Scale
Table IV. Correlations Among Scales on the Conners' Parent Rating Scale— Revised (CPRS-R)a
1
1.
2.
3.
4.
5.
6.
7.
Oppositional
Cognitive Problems
Hyperbctivity-Impulsivity
Anxious/Shy
Perfectionism
Social Problems
Psychosomatic
2
.57b
.50b
.51b
.37b
.13b
.43b
.44b
3
—
.58b
.55b
.49b
.30b
-.02
.45b
.42b
.36b
.12b
.35b
.33b
—
4
5
6
7
.38b
.33b
.41b
.17b
.49b
.44b
.42b
.40b
.17b
—
.40b
.36b
.24b
.34b
.15b
.33b
.34b
—
.26b
.39b
.34b
.00
.17b
.27b
—
.12b
.14b
aMales (n = 1,101) above the diagonal and females (n = 1,099) below.
b
p < .01.
110.12, p < .001], a significant main effect was found
for age group [F(2, 2,194) = 10.16, p < .001], and
the interaction of Group Age x Sex was significant
[F(2, 2,194) = 4.04, p < .05]. Using univariate analysis of variance for age group, the 3- to 7-year-olds
were rated significantly higher than the 8- to 12-yearolds [F(l, 2,194) = 13.29, p < .001] and the 13- to
17-year-olds [F(l, 2,194) = 18.09, p < .001].
For the Hyperactivity-Impulsivity scale, males
were rated significantly higher than females [F(l,
2,194) = 45.23, p < .001] and a significant main effect was found for age group [F(2, 2,194) = 69.70,
p < .001]; the interaction was not significant. Using
univariate analysis of variance for age group, the 3to 7-year-olds were rated significantly higher than the
8- to 12-year-olds [F(l, 2,194) = 77.31, p < .05] and
the 13- to 17-year-olds [F(l, 2,194) = 131.87, p <
.001], and the 8- to 12-year-olds were rated significantly higher than the 13- to 17-year-olds [F(l,
2,194) = 13.93, p < .001].
For the anxious/shy scale, females were rated
significantly higher than males [F(l, 2,194) = 4.81,
p < .05], a significant main effect was found for age
group [F(2, 2,194) = 87.43, p < .001], and the interaction was significant [F(2, 2,194) = 3.24, p < .05].
Using univariate analysis of variance for age group,
the 3- to 7-year-olds were rated significantly higher
than the 8- to 12-year-olds [F(l, 2,194) = 79.22, p <
.001] and the 13- to 17-year-olds [F(l, 2,194) =
171.79, p < .001], and the 8- to 12-year-olds were
rated significantly higher than the 13- to 17-year-olds
[F(l, 2,194) = 29.51, p < .001].
For the Perfectionism scale, females were rated
significantly higher than males [F(l, 2,194) = 6.17,
p < .05] and a significant main effect was found for
age group [F(2, 2,194) = 8.12, p < .001]; the interaction was not significant. Using univariate analysis
of variance for age group, the 13- to 17-year-olds
were rated significantly higher than the 3- to 7-year-
olds [F(1, 2,194) = 8.03, p < .005] and the 8- to 12year-olds [F(l, 2,194) = 15.43, p < .001].
For the Social Problems scale, the main effects
for sex and age group, and the effect for the interaction, were not significant.
For the Psychosomatic scale, females were rated
significantly higher than males [F(l, 2,194) = 4.78,
p < .05] and a significant main effect was found for
age group [F(2, 2,194) = 3.34, p < .05]; the interaction was not significant. Using univariate analysis of
variance for age group, the 3- to 7-year-olds were
rated significantly higher than the 13- to 17-year-olds
[F(l, 2,194) = 6.67, p < .01].
The intercorrelation matrix of the CPRS-R
scales is presented in Table IV , separately for males
and females. To examine possible gender differences
in the pattern of intercorrelations, the equality of the
correlation matrices was tested using EQS for Windows (version 5.1; Bentler, 1995). The criteria for determining the equality of the correlation matrices
were a nonnormed fit index (NNFI; Bentler & Bonett, 1980) greater than .900 and a comparative fit index (CFI; Bentler, 1990) greater than .900. Results
indicated that the pattern of intercorrelations for the
CPRS-R scales was virtually identical across the
sexes (NNFI = .988 and CFI = .989). A similar pattern of results was found when the equality of the
correlation matrices among the three age groups was
tested using EQS (NNFI = .956 and CFI = .962).
STUDY 3: CRITERION VALIDITY
Method
Participants
Two groups of children were used in the present
study. The first group consisted of 91 children (68
264
Conners, Sitarenios, Parker and Epstein
Table V. Means and Standard Deviations for the Non-ADHD (n = 91) and ADHD (n = 91)
Groups on the Conners' Parent Rating Scale— Revised (CPRS-R)a
Non-ADHD
CPRS-R Scale
Oppositional
Cognitive Problems
Hyperactivity-Impulsivity
Anxious/Shy
Perfectionism
Social Problems
Psychosomatic
ADHD
Mean
(SD)
Mean
(SD)
t
P
4.26
5.17
1.97
2.43
3.78
0.62
1.28
(3.99)
(6.50)
(3.43)
(2.90)
(4.21)
(1.19)
(2.07)
10.83
22.64
10.65
4.14
2.91
3.92
3.04
(6.99)
(7.97)
(6.70)
(3.89)
(3.83)
(4.03)
(3.07)
7.79
16.20
11.00
3.36
1.45
7.49
4.55
<.001
<.001
<.001
<.001
.149
<.001
<.001
aADHD = attention deficit/hyperactivity disorder.
males and 23 females) who met the following criteria: (a) parent and/or teacher referral to an outpatient ADHD clinic due to reported problems with inattention, hyperactivity, and/or impulsivity; (b)
independent diagnosis of ADHD by psychologist
and/or psychiatrist using Diagnostic and Statistical
Manual for Neutral Disorders (4th ed.) (DSM-IV;
American Psychiatric Association, 1994) criteria for
ADHD. Eighty-four percent of the participants were
European American, 8.8% were African American,
1.1% were Hispanic, and 6.1% were other; the mean
age was 10.16 years (SD = 3.40).
The second group (non-ADHD) consisted of 91
children (68 males and 23 females) from Studies 1 and
2 who were randomly selected and matched with the
ADHD sample on the basis of age, sex, and ethnicity.
Procedure
For participants in the ADHD sample, the
CPRS-R information was obtained as part of routine
clinical assessment.
Results
Table V presents means and standard deviations
for the CPRS-R scales for the ADHD and nonADHD groups. The ADHD group was rated significantly higher (using Mests) than the non-ADHD
group on the Oppositional scale, the Cognitive Problems scale, the Hyperactivity-Impulsivity scale, the
Anxious/Shy scale, the Social Problems scale, and the
Psychosomatic scale; there was no significant difference between the two groups on the Perfectionism
scale.
A direct discriminant function analysis was performed using CPRS-R scales as predictors of mem-
bership in the two groups (ADHD vs. non-ADHD).
Discriminant function scores were subsequently used
to classify the 182 children into ADHD and nonADHD groups. The results of this classification are
presented in Table VI. Following the definitions and
procedures outlined by Kessel and Zimmerman
(1993), a variety of diagnostic efficiency statistics
were calculated for the CPRS-R from these classification results: sensitivity was 92.3%, specificity was
94.5%, positive predictive power was 94.4%, negative
predictive power was 92.5%, false positive rate was
5.5%, false negative rate was 7.7%, kappa was .868,
and the overall correct classification rate was 93.4%.
GENERAL DISCUSSION
Redevelopment and restandardization of the
CPRS has produced a revised parent rating scale
with better psychometric properties than previous
versions. Scale construction was performed systematically, comprehensively, and in accordance with
psychometric standards (American Psychological Association, 1985), resulting in a definitive factor structure and representative normative data. In addition,
the revised scale's content contains fewer items, yet
provides a more comprehensive assessment and specific focus on ADHD-related behaviors than the
Table VI. Classification Results (ADHD vs. Non-ADHD) for
the Conners' Parent Rating Scale— Revised (CPRS-R)a
Diagnosis
Test
ADHD
Non-ADHD
Total
Present
Absent
84
7
5
86
89
93
Total
91
91
182
aADHD = attention deficit/hyperactivity disorder.
Revised Conners' Parent Rating Scale
original CPRS. With greater focus on ADHD-related
behaviors and concordance between scale items and
current conceptualizations of ADHD, the CPRS-R
provides better discriminatory power for detecting
ADHD children than previous scale versions.
Examination of the revised scale in terms of its
functional uses suggests that the CPRS-R will provide researchers and clinicians an effective tool for
assessing parental perceptions of ADHD-related behaviors. The foremost function of the CPRS-R will
be as a screening tool or as an adjunctive instrument
to a comprehensive assessment. This study's results
suggest that the CPRS-R is effective at discriminating ADHD children from normal children. Further,
ratings of children throughout North America can be
compared to normative data from a large, representative sample in order to provide a measure of
deviance or severity. Reliability estimates also suggest that accurate measures of parental perceptions
may be obtained. Consistent with the original forms'
use (Conners, 1994), the CPRS-R can also be used
as a clinician checklist when performing a clinical interview. Indeed, the factor structure of the CPRS-R
represents several categories of behavior which are
either directly related to ADHD symptoms (e.g., hyperactivity) or comorbid with ADHD (e.g., oppositional behavior) thereby providing a clinician with
problem domains upon which an interview could be
focused.
The other major use of the CPRS-R will likely
be to monitor treatment and to assess treatment outcome. Additional research needs to be conducted to
determine the utility of the CPRS-R in accomplishing this function. However, since the CPRS-R factor
structure comprehensively assesses many ADHD-related behaviors, some of which (e.g., HyperactivityImpulsivity) have proven to be susceptible to change
as a result of typical ADHD interventions (e.g., psychostimulant treatment), it seems likely that the
CPRS-R will provide a behavior-specific measure of
treatment outcome.
In comparison to the factor structure used for
scoring the original CPRS (Blouin et al, 1989), the
CPRS-R factor structure is quite similar, especially
in regard to factors assessing internalizing symptomatology. The CPRS-R factor structure retains the
Psychosomatic and Anxious/Shy factors from the
original scale both in form and name. The CPRS-R
Perfectionism factor is largely the same as the original Obsessive/Compulsive factor except that the label
has been modified to more accurately reflect the behavioral symptomatology encompassed by this factor.
265
In regards to externalizing behavior factors, the
factor structure has changed somewhat. A new Cognitive Problems factor includes symptoms consistent
with the DSM-IV ADHD inattentive domain. This
factor also encompasses academic difficulties with
items assessing handwriting, spelling, and arithmetic.
The clustering of academic difficulties with inattention problems on the same factor is supported by the
factor structure derived from a national sample of
parent ratings (Achenbach, Howell, Quay, & Conners, 1991) and is concordant with the factor structure of the Conners Teacher Rating Scale—Revised
(Conners, Sitarenios, Parker, & Epstein, 1998). As
suggested by Conners et al. (1998), this clustering of
academic and inattention problems may be explained
by the high relation between academic achievement
and inattention problems in elementary school children (Hinshaw, 1991). The original CPRS did not
adequately assess for either inattention or academic
achievement; therefore there are no corresponding
factors on the original CPRS. In fact, the lone CPRS
inattention item, fails to finish things s/he startsshort attention span, loads on both the CPRS Conduct Problem and Hyperactive/Immature factors.
The other domain of ADHD symptoms, hyperactive/impulsivity, is assessed by the CPRS-R Hyperactivity factor. This factor has items covering both
hyperactive and impulsive symptoms. The original
CPRS had two factors which assessed these categories of behaviors labeled Hyperactive/Immature and
Restless/Disorganized. Both factors contained extraneous behaviors discordant with their label (e.g.,
"cries easily" on the Hyperactive/Immature factor)
and neither comprehensively assessed hyperactive or
impulsive symptoms. However, the CPRS-R Hyperactivity factor contains items which all relate to the
hyperactive/impulsive domain of behavior and which
assess a wide variety of symptoms related to this
symptom cluster. Thus scores on this scale are much
more reflective of hyperactive/impulsive symptoms.
Similarly, the original CPRS had a Conduct Disorder factor and Antisocial factor, both of which assessed symptoms consistent with Oppositional Defiant Disorder and Conduct Disorder diagnoses.
However, problems with the CPRS Conduct Disorder factor included the fact that it assessed a wide
variety of externalizing symptoms other than those
behaviors associated with Conduct Disorder including items associated with ADHD. Thus, this factor
was more a measure of externalizing behavior than
CD specifically. The CPRS-R has a single Oppositional factor that more accurately and specifically
266
assesses behaviors consistent with ODD and CD and
excludes those externalizing behaviors associated
with ADHD thus providing a more useful and distinct measure of oppositional behavior.
The last factor on the CPRS-R is the Social
Problems factor, which was absent on the original
CPRS. Since social problems are often present in
children with externalizing behaviors, this symptom
category is extremely important to assess. Indeed,
several investigators have suggested the relevance of
social difficulties in the long-term outcome and prognosis of ADHD children (Barkley, 1990; Landau &
Moore, 1991). However, the relatively low test-retest
reliability of this scale suggests caution in its use and
the need to develop a more reliable version of this
scale.
A useful advantage of the CPRS-R factor structure is that it is similar in factor content to the revised
Conners Teacher Rating Scale (CTRS-R; Conners et
al., 1998). All of the CPRS-R factors correspond with
CTRS-R factors.6 Corresponding factors across these
two scales provide the opportunity to directly compare parent and teacher ratings of a specific behavioral domain, using norms obtained on the same children, thus providing measures of cross-informant
consistency and possibly providing information about
situation-specific behavioral patterns across school
and home environments. Indeed, assessing problems
across multiple environments is a requirement for a
DSM-IV ADHD diagnosis.
Gender differences on the CPRS-R revealed
higher ratings for males on the Cognitive Problems,
Hyperactivity-Impulsivity, and Oppositional factors
while girls were rated higher on the Anxious/Shy,
Psychosomatic, and Perfectionism factors. These gender differences on the CPRS-R corroborate the common finding that boys tend to be rated higher on Externalizing factors while girls are rated higher on
Internalizing factors (Achenbach et al., 1991; Anderson, Williams, McGee, & Silva, 1987; Costello et al.,
1985; Offord, Boyle, Szatmari, Rae, et al., 1987;
Velez, Johnson, & Cohen, 1989). Achenbach et al.
(1991) pointed out that sex differences on rating
scales are small in normative samples, but that, in
troubled children, these differences become large
since there is a large degree of externalizing problems in troubled boys and internalizing problems in
troubled girls. While this may be true, the observed
6
There is no corresponding Psychosomatic factor on the CTRS-R
since teachers were not asked to rate these items because of experience suggesting that they did so unreliably.
Conners, Sitarenios, Parker and Epstein
sex differences in our normative sample, especially
on Externalizing factors, were quite large and suggest
a normative trend for males to express a far greater
amount of externalizing symptoms than females.
Age differences were found on several factors
with children receiving lower ratings with age on the
Cognitive Problems, Hyperactivity/Impulsivity, Anxious/Shy, and Psychosomatic factors. Similar declines
in problem scores have been found in other studies
(Achenbach & Edelbrock, 1981; Achenbach, Hensley, Phares, & Grayson, 1990). This finding likely
reflects normative developmental trends in which
certain behaviors (e.g., excitable) generally decrease
with age. The CPRS-R Perfectionism factor showed
an opposite effect, with higher ratings with increased
age. This reverse effect possibly reflects the phenomenon that many developmentally sanctioned obsessive-compulsive behaviors occur in early childhood (e.g., elaborate bedtime rituals) and are not
likely to be rated by parents as inappropriate or
problem behavior (March, Leonard, & Swedo, 1995).
However, as children grow older, ritualistic and perfectionistic behaviors become less socially accepted,
thus resulting in higher ratings on this factor for
older children.
In comparison to other parent rating scales, the
CPRS-R has comparable psychometric properties yet
measures ADHD and its associated behaviors more
specifically and comprehensively. Specifically, in
comparison to two of the more popular parent rating
scales, the Child Behavior Checklist (CBCL) and Revised Behavior Problem Checklist (RBPC), the
CPRS-R is the only checklist that contains scales related to both domains of ADHD behaviors, inattention and hyperactivity/impulsivity. The CBCL has a
single factor labeled Hyperactivity and the RBPC has
an Attention Problems-Immaturity factor. Measuring
the severity of both domains of ADHD behaviors
seems necessary for both comprehensive descriptive
and diagnostic purposes.
The CBCL includes factors not found in the
CPRS-R, including Depressed, Immature, Sexual,
and Uncommunicative. Despite attempts to enlarge
the CPRS-R item pool so as to reveal a factor of
depression, those items repeatedly became subsumed
under the Anxiety factor. Items relating to immaturity typically attached themselves to the Cognitive
Problems factor or were unstable in replication studies. Social communication problems are included in
the Social Problems factor. Long experience with
items regarding precocious or inappropriate sexuality
in the original parent scale indicated limited clinical
Revised Conners' Parent Rating Scale
usefulness and low item endorsement. However, this
highlights the problem of scales based upon frequency of endorsement. Though some items rarely
occur (e.g., items relating to psychosis), when they
do occur they are important. The tradeoff of having
a shorter scale with better user-compliance and acceptance, versus a longer scale covering many items
that are important but rare, was decided in favor of
brevity and focus in the current revision.
In summary, the CPRS-R provides a reliable,
accurate, and relatively brief measure of parental
perceptions of children's disruptive behavior. Parent
rating scales, such as the CPRS-R, are extremely
relevant for both clinical and research purposes.
They provide the opportunity to measure the most
common behavior problems, they are inexpensive to
administer, they have normative data for assessing
deviance, and they allow people who are integral to
the child's life, namely parents, to express their opinions about the target child. There is little reason not
to include a parental checklist as an adjunctive measure to any clinical assessment. Further, parental
checklists such as the CPRS-R provide a useful
measure for monitoring children's behavior over
time, especially during the course of a clinical or
medical intervention.
ACKNOWLEDGMENT
Preparation of this manuscript was partially supported by National Institute of Mental Health Grant
#MH01229 (C. Keith Conners, principal investigator).
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