Psychometric evaluation of a Swedish version of the Reiss Screen for Maladaptive Behavior

Statistical modelling studies examining the dimensional structure of psychopathology experienced by adults with intellectual disabilities: Systematic review

Diagnosing mental ill-health using categorical classification systems has limited validity for clinical practice and research. Dimensions of psychopathology have greater validity than categorical diagnoses in the general population, but dimensional models have not had a significant impact on our understanding of mental ill-health and problem behaviours experienced by adults with intellectual disabilities. This paper systematically reviews the methods and findings from intellectual disabilities studies that use statistical methods to identify dimensions of psychopathology from data collected using structured assessments of psychopathology. The PRISMA framework for systematic review was used to identify studies for inclusion. Study methods were compared to best-practice guidelines on the use of exploratory factor analysis. Data from the 20 studies included suggest that it is possible to use statistical methods to model dimensions of psychopathology experienced by adults with intellectual disabilities. However, none of the studies used methods recommended for the analysis of non-continuous psychopathology data and all 20 studies used statistical methods that produce unstable results that lack reliability. Statistical modelling is a promising methodology to improve our understanding of mental ill-health experienced by adults with intellectual disabilities but future studies should use robust statistical methods to build on the existing evidence base.

Examining the psychometrics of the Psychopathology Inventory for Mentally Retarded Adults-II for individuals with mild and moderate intellectual disabilities

With growing recognition of the occurrence of psychological disorders in individuals with intellectual disability (ID), researchers and clinicians alike have placed emphasis on developing measures to assess for psychopathologies in this population. Despite an increased interest in the topic, there is still a dearth of psychometrically robust measures available to assess for psychopathology in adults with mild and moderate ID. The purpose of this study was to examine the psychometric properties of a revised measure for psychopathology in individuals with mild and moderate ID, the Psychopathology Inventory for Mentally Retarded Adults - second edition (PIMRA-II). Internal consistency, inter-rater reliability, and test-retest reliability were investigated. Validity was studied via convergent validity by comparing the PIMRA-II to the Assessment of Dual Diagnosis (ADD) and via discriminate validity by comparing the PIMRA-II to the Social Performance Survey Schedule (SPSS) prosocial scores. Lastly, an exploratory factor analysis was conducted to determine the factor structure of the scale.

The French version of the Reiss Screen for Maladaptive Behavior: factor structure, point prevalence and associated factors

The main aims of the present study were to examine the factor structure and the internal consistency of the factors in the French version of the Reiss Screen of Maladaptive Behavior in a French-speaking European sample. The prevalence of psychopathology and the influence of associated factors were also examined. The Reiss Screen was administered to 467 adults (age range: 18-73) with intellectual disability living in the French-speaking regions of Switzerland and Belgium. A confirmatory factor analysis was performed to replicate the original factor structure. Internal consistency was examined by using Cronbach's alpha. Analyses of variance were computed to study the influence of gender, age and Down syndrome etiology. The original factor structure of the Reiss Screen was replicated. The overall rate of psychopathology in the sample was 37%. No linear relationship between age and psychopathology was found. However, adults aged less than 26 years had lower scores than older adults on several psychopathological domains. Males had higher scores than females on the Autism and the Avoidant Disorder subscales. Participants with Down syndrome had lower scores on all domains, with the exception of the Autism subscale. The results of this study suggest that the French version of the Reiss Screen can be a useful tool to detect psychopathology in adults with intellectual disability.

Scaling methods to measure psychopathology in persons with intellectual disabilities

Psychopathology prior to the last four decades was generally viewed as a set of problems and disorders that did not occur in persons with intellectual disabilities (ID). That notion now seems very antiquated. In no small part, a revolutionary development of scales worldwide has occurred for the assessment of emotional problems in persons with ID. The first standardized test to emerge was the Psychopathology Instrument for Mentally Retarded Adults (PIMRA) in 1984. Since that time, an impressive number of measures of general psychopathology have emerged for adults and children as well as for persons across the full range of levels of ID. The purpose of this review was to provide a description of available measures, to review papers published on these measures, and to discuss emerging trends in test development. The trends in this body of information for enhancing differential diagnosis of psychopathology in persons with ID are discussed.

Characteristics of instruments screening for depression in adults with intellectual disabilities: systematic review

The aim of this study was to obtain information on feasibility, reliability and validity of available instruments screening for depression applied in people with intellectual disabilities (ID). Therefore, literature was systematically reviewed. For self-report, the Glasgow Depression scale for people with a Learning Disability appears most promising (internal consistency α=0.90, test-retest reliability r=0.97, sensitivity 96% and specificity 90%). For informant-report three instruments seem promising: the Assessment of Dual Diagnosis (internal consistency α=0.77 and α=0.91, test-retest reliability r=0.94, interrater reliability r=0.98), the Reiss Screen for Maladaptive Behaviour (internal consistency α=0.58-0.83, interrater reliability r=0.61-0.84, sensitivity 80%, specificity 83%), and the Children's Depression Inventory (internal consistency α=0.86, sensitivity 83%, specificity 93%). None of these three instruments have been studied satisfactorily in this group, yet. More research on psychometric properties, especially sensitivity and specificity in the ID population, is needed.

Instruments for the detection of depressive symptoms in people with intellectual disabilities: a systematic review

Affective disorders, particularly depression, are common in adults with intellectual disabilities. However the detection of these disorders is hindered by the varied presentation of depressive symptoms across the range of intellectual disability. We undertook a systematic review of the available English-language diagnostic instruments for depressive disorders for adults with all levels of intellectual disability. We appraised the studies based on the instruments' psychometric properties, sensitivity and specificity. We included 21 of 28 identified studies which contained original data on validity and reliability; the ;gold standard' ranged from clinical opinion to other established instruments, some of which had limited validation in people with intellectual disability. In view of the benefits of psychological treatments for common mental disorders, it is important to develop instruments to be used in monitoring cognitive as well as behavioural outcomes for people with intellectual disability and depressive disorders.

Psychometric properties of Psychopathology checklists for Adults with Intellectual Disability (P-AID) on a community sample of adults with intellectual disability

The DC-LD is a new classification system providing operationalized diagnostic criteria in recognition of lacking applicability of standard psychiatric criteria for adults with intellectual disability. This study attempts to evaluate internal consistency, inter-rater reliability and factor structure of the Psychopathology Checklists for Adults with Intellectual Disability (P-AID), a set of checklists developed from the DC-LD. The P-AID checklists comprising 10 psychiatric diagnoses and 8 types of problem behaviors were filled in by staff at community based homes for adults with intellectual disability in Western Norway. A total of 593 were returned (66%) of which 83 had two sets of checklists. Intellectual disability was administratively defined. Alpha (alpha) values for the total P-AID checklists indicating high internal consistency. The inter-rater reliability measured by ICC showed values between 0.63 and 0.88 in 8 of 10 psychopathology Checklists. Factor analysis indicated four orthogonal units measured by the P-AID. Issues regarding sensitivity and specificity are discussed. This study is the first attempt to develop and evaluate Psychopathology Checklists based on the DC-LD. The results from this study indicate the P-AID can be used in identifying mental health needs at a detailed diagnostic level.

A psychometric evaluation of a Swedish version of the psychopathology inventory for mentally retarded adults (PIMRA)

Given the difficulties with symptom identification and the assessment of mental health problems in persons with intellectual disabilities (ID) there has been a focus on the development of relevant assessment schedules for persons with ID. A Swedish version of the psychopathology inventory for mentally retarded adults (PIMRA, informant version), an instrument designed for identification of specific mental health problems in persons with ID, was evaluated in terms of inter-rater reliability, internal consistency, item grouping, criterion and concurrent validity based on a sample of 101 adults with different levels of ID. The Swedish version of the PIMRA had low inter-rater agreement on specific items but good agreement on low or high total score. In order to investigate internal validity, principal component analyses (PCA) were conducted in steps. Consequently, the majority of the 26 items, which remained after three PCA analyses, were grouped in a pattern approximating five of the original PIMRA subscales. The present analysis identified no item grouping matching the original Affective disorder subscale. Based on these results a revised Swedish version was developed. The concurrent validity analysis yielded a strong association between the total scores of the PIMRA and Reiss Screen for Maladaptive Behaviour (RSMB), between subscales on both instruments describing psychotic symptoms and between the RSMB subscale Aggressive behaviour and the PIMRA subscale Adjustment problems. The outcome of the criterion validity analysis indicated that individuals with a clinical diagnosis obtained higher total PIMRA scores than individuals without a clinical diagnosis and a comparison between the PIMRA subscale Psychosis and the clinical diagnosis indicating psychoses according to DSM-III-R or DSM-IV yielded a higher specificity than sensitivity measure. The results indicate that the PIMRA had a potential to identify individuals with mental health problems in persons with different levels (mild, moderate and severe) of ID and identify individuals with a specific mental disorder. Thus, professionals might use the PIMRA as a complement in the diagnostic process.