G. Leonard Burns

Revision of the Padua Inventory of obsessive compulsive disorder symptoms: Distinctions between worry, obsessions, and compulsions

The Padua Inventory (PI), a self-report measure of obsessive and compulsive symptoms, is increasingly used in obsessive compulsive disorder (OCD) research. Freeston, Ladouceur, Rheaume, Letarte, Gagnon and Thibodeau (1994) [Behaviour Research and Therapy, 32, 29-36], however, recently showed that the PI measures worry in addition to obsessions. In an attempt to solve this measurement problem, this study used a content distinction between obsessions and worry to revise the PI. The revision was constructed to measure five content dimensions relevant to OCD i.e. (1) obsessional thoughts about harm to oneself or others; (2) obsessional impulses to harm oneself or others; (3) contamination obsessions and washing compulsions; (4) checking compulsions; and (5) dressing/grooming compulsions. A total of 5010 individuals participated in the study, 2970 individuals completing the PI and the Penn State Worry Questionnaire (PSWQ) and an additional 2040 individuals completing only the PI. The results provided support for the reliability and validity of the revision. In addition, the revision of the PI was more independent of worry, as measured by the PSWQ, than the original PI. Support was thus found for the validity of the content distinction between obsessions and worry. The importance of this content distinction is also discussed for the evaluation of other hypothesized distinctions between obsessions and worry.

The utilization of nonpatient samples in the study of obsessive compulsive disorder

Obsessive compulsive disorder (OCD) is increasingly studied in nonpatients, primarily through the selection of individuals who score high on a self-report measure of OCD. The usefulness of this methodology for understanding OCD presupposes that some of the individuals in the high-scoring group meet diagnostic criteria for OCD, that the obsessive-compulsive behaviors in the high-scoring individuals are stable across time to a certain degree, and that the features associated with OCD in patients also are found in the high-scoring nonpatients. Two studies are reported which provide support for these three assumptions. Together the studies suggest that OCD can be productively examined by the selection of individuals who score high on a self-report measure of OCD. Cautions in the use of this methodology for the study of OCD are also noted.

A Multitrait-Multisource Confirmatory Factor Analytic Approach to the Construct Validity of ADHD Rating Scales

Confirmatory factor analysis was used to model a multitrait-multisource design to evaluate the construct validity of attention-deficit/hyperactivity disorder (ADHD) rating scales. The 2 trait factors were the ADHD inattention and hyperactivity/impulsivity dimensions. The 2 source factors were parents and teachers. In Study 1, parents and teachers rated 1,475 Australian elementary school children on the ADHD symptoms. In Study 2, parents and teachers rated 285 Brazilian elementary school children on the ADHD symptoms. Similar results occurred in both studies with most of the ADHD symptoms containing more source than trait variance, thus providing weak evidence for the convergent and discriminant validity of the symptoms as measured by rating scales. The study outlines the implications of such strong source effects for understanding ADHD.

Maudsley obsessional ― compulsive inventory: obsessions and compulsions in a nonclinical sample

Obsessive-compulsive disorder is increasingly being studied in nonclinical samples. The self-report instruments used to select these samples, however, have not been validated with a diagnostic interview. This study thus investigated the predictive validity of the Maudsley Obsessional-Compulsive Inventory (MOCI) using the Anxiety Disorders Interview Schedule (ADIS), a semi-structured interview created according to DSM-III guidelines. Four sections of the ADIS--generalized anxiety disorder, simple phobia, social phobia and obsessive-compulsive disorder--were administered to 11 individuals who scored in the top 2% and 11 individuals who scored in the normal range of the MOCI 6-7 months prior to the interview. High nonclinical MOCI scorers reported more frequent and severe obsessions and compulsions as well as greater disturbance by these symptoms. In addition, the high MOCI group experienced more general worry and interference from worry, and more frequent and severe physiological symptoms when they worry. However, the two groups did not differ in terms of simple and social phobia symptoms. High MOCI scorers thus did not report a broad range of anxiety symptoms or fears, but specific obsessions and compulsions. These results provide further support for the validity of the MOCI in nonclinical samples over a 6-7 month interval.

A confirmatory factor analysis on the DSM-IV ADHD and ODD symptoms: What is the best Model for the organization of these symptoms?

Confirmatory factor analysis (CFA) was used to evaluate five different models for the organization of the DSM-IV ADHD and oppositional defiant disorder (ODD) symptoms (Model 1: a single factor model; Model 2: an ADHD and ODD two factor model; Model 3a: an inattention (INA), hyperactivity/impulsivity (HYP/IMP), and ODD three factor model; Model 3b: an INA, HYP/IMP, and ODD three factor model where the three IMP symptoms cross-load on the ODD factor; Model 4: an INA, HYP, IMP, and ODD four factor model). To evaluate these models, maternal ratings of ADHD and ODD symptoms were obtained at outpatient pediatric clinics on 742 children not in treatment and 91 children in treatment for ADHD. Model 3a resulted in a good fit as well as a significantly better fit than Model 2. Model 3a was also equivalent across treatment status, gender, and age groupings for the most part. Though Models 3b and 4 provided a statistically better fit than Model 3a, the improvement in fit was small and other model selection criteria argued against these more complex models.

Internal Validity of the Disruptive Behavior Disorder Symptoms: Implications from Parent Ratings for a Dimensional Approach to Symptom Validity

A dimensional approach was used to evaluate the internal validity of the DSM-III-R ADHD-inattention, ADHD-hyperactivity/impulsivity, oppositional defiant disorder (ODD), and conduct disorder (CD) symptoms (i.e., whether a symptom has a stronger correlation with its own dimension than the other three). Parents rated 4,019 children between the ages of 2 and 19 on these symptoms. The results showed that 5 of the 6 inattention symptoms, 3 of the 4 hyperactivity symptoms, 1 of the 4 impulsivity symptoms, 6 of the 9 oppositional defiant disorder symptoms, and 8 of the 11 CD symptoms had significant internal validity. Confirmatory factor analysis (CFA) found support for inattention, hyperactivity/impulsivity, oppositional defiant, and conduct disorder dimensions. Multiple-group CFA also found support for factor pattern and loading invariance across gender. The implications of these results as well as the merits of the dimensional approach to symptom validity are discussed in the context of the DSM-IV changes in ADHD, ODD, and CD.

Compulsive activity checklist and the maudsley obsessional-compulsive inventory: Psychometric properties of two measures of obsessive-compulsive disorder

The psychometric properties of two measures of obsessive-compulsive symptoms are described in this study. The Compulsive Activity Checklist (CAC) and the Maudsley Obsessional-Compulsive Inventory (MOCI) were administered to a nonclinical American sample of 579 college students. Original American norms are presented for the CAC and the MOCI. Both measures demonstrated good internal consistency and testretest stability over a 6–7 month interval. Principal components analysis extracted three CAC factors: washing, checking and personal hygiene. Four factors were extracted for the MOCI: washing, checking, doubting and strictness. Both measures showed good convergent and divergent validity with the nine subscales of the SCL-90-R, though the results were slightly stronger for the MOCI. The results also provide additional evidence that the CAC and MOCI are measuring different aspects of obsessivecompulsive symptoms.

The Influence of ADHD–Hyperactivity/Impulsivity Symptoms on the Development of Oppositional Defiant Disorder Symptoms in a 2-Year Longitudinal Study

The structural relations among ADHD–inattention (IN), ADHD–hyperactivity/impulsivity (H/I), and oppositional defiant disorder (ODD) factors were examined in a 2-year longitudinal study with 752 children. Structural equation procedures showed that higher scores on the H/I factor in Year 1 were associated with higher scores on ODD factor in Years 2 and 3. Higher scores on the H/I factor in Year 2 were also associated with higher scores on ODD factor in Year 3. The ODD factor did not predict the H/I and IN factors in subsequent years. The IN factor did not predict the ODD and H/I factors in subsequent years and the H/I factor did not predict the IN factor. The ability of the H/I factor to predict the subsequent ODD factor occurred even after taking into account the ability of the ODD, H/I, and IN factors to predict themselves across time. These results suggest that the H/I aspect of ADHD influences the development of ODD behavior.

Factor Structure of the Eyberg Child Behavior Inventory: A Parent Rating Scale of Oppositional Defiant Behavior Toward Adults, Inattentive Behavior, and Conduct Problem Behavior

Used the Eyberg Child Behavior Inventory (ECBI) to measure disruptive behavior problems in children and adolescents. A controversy exists, however, on the dimensional structure of the ECBI. To evaluate this issue, an exploratory factor analysis was first performed on a sample of 1,263 children and adolescents. This analysis identified 3 meaningful factors (i.e., Oppositional Defiant Behavior Toward Adults, Inattentive Behavior, and Conduct Problem Behavior) and a fourth, poorly defined factor. A confirmatory factor analysis (CFA) evaluated the fit of the 3 meaningful factors in a second sample of 1,264 children and adolescents. The 3-factor model with 2 correlated errors provided a excellent fit. This 3-factor model also provided a significantly better fit than 2- and 1-factor models. Multiple group CFA indicated that the factor pattern, item-factor loadings, factor correlations, and correlated errors were equivalent across the samples. The CFA on sex yielded similar results. Initial normative information is presented for boys (n = 1,322) and girls (n = 1,205) within 4 age ranges (i.e., 2-5, 6-9, 10-13, 14-17) for the 3 factors. The use of these 3 factors, especially Oppositional Defiant Behavior and Conduct Problem Behavior, should make the ECBI more useful as a screening and outcome measure.

Relation of sexual abuse and bulimia in college women

This study investigated the relation between self-report of prior sexual abuse and self-report of current eating behaviors consistent with bulimia. The subjects were 340 college women who completed the Bulimia Test and a modified version of Finkelhors Life Events Questionnaire, which inquires about experiences of sexual abuse. Bulimic women did not report a higher incidence of past intrafamilial sexual abuse than did the comparison group. However, bulimic women did report both significantly more experiences of extrafamilial sexual abuse after age 12 and that they had narrowly missed being sexually assaulted more often than did the comparison group of women. The findings provide limited support for the clinical belief that sexual abuse is associated with bulimia. It may be that perception of control is a mediator for the possible sexual abuse-bulimia relation.