The diagnostic adaptive behavior scale: evaluating its diagnostic sensitivity and specificity

Examining the Relationship between Adaptive Behavior and Intelligence

Adaptive behavior and intelligence are both essential components of defining and diagnosing intellectual disability. The exact relationship between these two constructs still warrants some clarification. Previous studies have examined the correlation between adaptive behavior and intelligence and have reported differing results. Overall, there seems to be agreement that a modest to moderate correlation exists between adaptive behavior and intelligence and that the strength of this relationship may increase as ability level decreases further below the population mean. Using the Diagnostic Adaptive Behavior Scale and a sample of 57 youth aged from 4 to 21 years old, we examined the correlation coefficients between the full-scale IQ scores and their scores obtained on conceptual, social, and practical adaptive skill domain scores, as well as the total adaptive behavior score. The results obtained indicated a modest to moderate correlation between adaptive behavior and intelligence. The strongest statistically significant correlation coefficient was between the full-scale IQ score and the conceptual adaptive skills domain score (r = 0.64). The correlation between the full-scale IQ score and the practical adaptive skills domain (r = 0.39) and social adaptive skills domain (r = 0.28; ns) were more modest. The correlation coefficient between the full-scale IQ score and the total adaptive behavior score also showed a moderate relationship with intelligence (r = 0.46). These findings are consistent with previous research, documenting that adaptive behavior and intelligence are two related but independent constructs. We discuss these findings and their implications.

The French Version of the DABS: Adaptation Process and Preliminary Field Test

The aim of this study was to develop a transcultural adaptation of the Diagnostic Adaptive Behavior Scale (DABS) in French and to perform a field evaluation of the adapted version of the tool (DABS-F). Eight experts in intellectual and developmental disabilities (IDD) and two professional translators formed two committees to translate the instrument. Thirty-four independent experts in IDD rated the clarity and relevance of the DABS-F. Results indicated complete agreement between the two translation committees and also demonstrated very satisfactory levels of clarity and relevance for the DABS-F. The latter result can be considered as evidence of the content validity of the adapted tool. Adjustments for the few items that presented less satisfactory results are discussed.

Italian Diagnostic Adaptive Behavior Scale: Reliability and diagnostic accuracy compared with the Vineland-II

BACKGROUND

The Diagnostic Adaptive Behavior Scale (DABS) is a short scale with excellent properties to assess the conceptual, social, and practical adaptive behavior domains for the diagnosis of intellectual disability (ID) in individuals aged 4-21 years.

AIMS

Investigate the test-retest and inter-respondent reliability of the Italian adaptation of the DABS, verify its diagnostic accuracy in identifying individuals with ID and excluding individuals with typical development (TD), and compare its psychometric properties to those of the Vineland-II.

METHODS

Test-retest reliability: The same respondent completed the Italian DABS for the same assessed person at two separate times (n = 71). Inter-respondent reliability: Two respondents for the same assessed person completed the Italian DABS independently (n = 57). Diagnostic accuracy: The same respondent completed the Italian DABS and Vineland-II for the same assessed person (n = 378; 50 % ID, 50 % TD).

RESULTS

Italian DABS test-retest and inter-respondent correlation coefficients were excellent. Italian DABS sensitivity was 86 % and specificity was 99 %, Italian DABS Areas Under the ROC Curves were excellent (or good, practical skill domain), and comparable to the results reported for the Vineland-II.

CONCLUSIONS

The Italian DABS is an excellent measure to evaluate the adaptive behavior for ID diagnosis; it is comparable to the Vineland-II but being shorter, the Italian DABS requires less time to administer.

Diagnosing intellectual disability in people with fetal alcohol spectrum disorder: A function of which diagnostic manual is used?

Fetal alcohol spectrum disorder (FASD) is the largest known cause of intellectual disability (ID), and forensic experts are often called upon to determine if a defendant with FASD qualifies for a diagnosis of ID. Whether such a diagnosis is made may depend upon the diagnosing expert's choice of diagnostic manual: guidelines published by the American Association on Intellectual and Developmental Disabilities (now in its 12th edition [AAIDD-12]) or the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Although both manuals use the same three diagnostic "prongs" (i.e., intellectual deficits, adaptive deficits, and developmental onset), there are substantial differences in the way all three prongs are assessed-differences that increased with the publication of AAIDD-12. In particular, AAIDD-12 uses a bureaucratic "disability" model, with narrow emphasis on a small number of quantitative indicators and limited opportunity for clinical integration, while DSM-5 (and the little-changed forthcoming DSM-5-TR) uses a medical "disorder" model, with flexible reliance on a broad array of indicators and opportunity for clinical integration. The origins and nature of these differences are explored, and an argument is made that compared to the AAIDD formulation, the DSM model provides a more valid basis for forensic diagnosis of ID in individuals with FASD.

Behavioral and emotional problems of toddlers with autism spectrum disorder: Effects of parents' sociocultural level and individual factors

BACKGROUND

Toddlers with autism spectrum disorder (ASD) show higher prevalence and severity of Behavioral and Emotional Problems (BEP) than their peers without ASD.

AIMS

Investigating the effects of parental factors, i.e., mothers' and fathers' age and Sociocultural Level (Socioeconomic Status, Cultural Capital, and Social Capital), and individual factors, i.e., toddles' age, birth order, general development, autism symptom severity, and adaptive behavior, on the expression of BEP in toddlers with ASD.

METHODS

Participants were 148 toddlers with ASD (aged 18-37 months) and both their parents. BEP were measured with the Child Behavior Checklist 1½-5 (CBCL) Syndrome and Pervasive developmental problems (PDD) DSM-oriented scales, general development with the Griffiths Mental Development Scales (GMDS), autism symptom severity with the Autism Diagnostic Observation Schedule-2 (ADOS-2), and adaptive behavior with the Vineland-II Adaptive behavior composite.

RESULTS

Vineland-IIAdaptive behavior composite was negatively associated with the majority of the CBCL scales. In contrast, the ADOS-2 Restrictive and repetitive behavior was negatively and the ADOS-2 Social affect, toddlers' age, and birth order were positively associated with only a few of the CBCL scales (e.g., PDD). GMDS scores were not associated with any CBCL scales. Mothers' age and fathers' Cultural Capital and Social Capital dimensions were negatively associated with specific CBCL scales, even when considered in addition to individuals' factors.

CONCLUSIONS

Individual and parental factors simultaneously affect the expression of BEP and should be considered for clinical decisions.

A quality of life supports model: Six research-focused steps to evaluate the model and enhance research practices in the field of IDD

In the field of intellectual and developmental disabilities (IDD) the constructs of quality of life and supports have been combined into a Quality of Life Supports Model (QOLSM) that is currently used internationally for supports provision, organization transformation, and systems change. With the model's increasing and widespan use in research and practice, there is a need to evaluate the model's impact at the individual, organization, and systems levels. The purpose of this article is to outline six specific research-focused evaluation steps that allow researchers to evaluate the model and thereby enhance research practices is the field of IDD. These steps involve: (1) operationalizing components of the QOLSM; (2) relating QOLSM components to the type of research planned and intended outcome indicators; (3) gathering evidence and establishing its credibility; (4) interpreting and communicating the results; (5) implementing research outcomes at the level of the microsystem, mesosystem and macrosystem; and (6) judging the impact of the model. These steps delineate a research framework that is based on a systematic approach to evidence-based practices and enhanced research practices in the field of IDD.

The Application of Adaptive Behaviour Models: A Systematic Review

Adaptive behaviour has been viewed broadly as an individual’s ability to meet the standards of social responsibilities and independence; however, this definition has been a source of debate amongst researchers and clinicians. Based on the rich history and the importance of the construct of adaptive behaviour, the current study aimed to provide a comprehensive overview of the application of adaptive behaviour models to assessment tools, through a systematic review. A plethora of assessment measures for adaptive behaviour have been developed in order to adequately assess the construct; however, it appears that the only definition on which authors seem to agree is that adaptive behaviour is what adaptive behaviour scales measure. The importance of the construct for diagnosis, intervention and planning has been highlighted throughout the literature. It is recommended that researchers and clinicians critically review what measures of adaptive behaviour they are utilising and it is suggested that the definition and theory is revisited.

Development and Standardization of the Diagnostic Adaptive Behavior Scale: Application of Item Response Theory to the Assessment of Adaptive Behavior

The Diagnostic Adaptive Behavior Scale (DABS) was developed using item response theory (IRT) methods and was constructed to provide the most precise and valid adaptive behavior information at or near the cutoff point of making a decision regarding a diagnosis of intellectual disability. The DABS initial item pool consisted of 260 items. Using IRT modeling and a nationally representative standardization sample, the item set was reduced to 75 items that provide the most precise adaptive behavior information at the cutoff area determining the presence or not of significant adaptive behavior deficits across conceptual, social, and practical skills. The standardization of the DABS is described and discussed.

A study on the usefulness and reliability of the "Scheme of Appraisal of Emotional Development" (SAED) for persons with ID using direct observation in a group-based assessment procedure

INTRODUCTION

Whereas instruments for the assessment of intellectual and social abilities are widely available, instruments for the evaluation of emotional development of persons with intellectual disabilities (ID) are rare. The Scheme of Appraisal of Emotional Development (SAED), an internationally used tool developed by Dosen (2005a. Journal of Intellectual Disability Research, 49, 1, 2005b. Journal of Intellectual Disability Research, 49, 9), is one of the latter and is based on interviews with caregivers. The present study aims to investigate the internal consistency and interrater-reliability by changing the interview procedure into a direct observation and evaluation approach by a whole team instead of by one expert.

METHOD

The level of emotional development of 175 patients admitted to a psychiatric inpatient unit specialized in the treatment of adults with ID was evaluated with the SAED by the treatment team after an observation period of up to two weeks. The inter- and intra-rater-reliability was assessed by direct observation of the behaviour of an additional 50 patients by two pairs of raters.

RESULTS

The internal consistency of the SAED dimensions, once rated by team approach, is excellent, and the reliability measures show also good statistical results.

CONCLUSION AND IMPLICATIONS

The evaluation of the level of emotional development using the SAED by a group-led and/or direct observational procedure show to be a reliable and useful approach. The group-based procedure yields equal results compared with the usual interview guidelines and might lead to an additional training effect within the respective teams. The rater-reliability measures align with those reported in other studies.

Validity and reliability of the Diagnostic Adaptive Behaviour Scale

BACKGROUND

The Diagnostic Adaptive Behaviour Scale (DABS) is a new standardised adaptive behaviour measure that provides information for evaluating limitations in adaptive behaviour for the purpose of determining a diagnosis of intellectual disability. This article presents validity evidence and reliability data for the DABS.

METHOD

Validity evidence was based on comparing DABS scores with scores obtained on the Vineland Adaptive Behaviour Scale, second edition. The stability of the test scores was measured using a test and retest, and inter-rater reliability was assessed by computing the inter-respondent concordance.

RESULTS

The DABS convergent validity coefficients ranged from 0.70 to 0.84, while the test-retest reliability coefficients ranged from 0.78 to 0.95, and the inter-rater concordance as measured by intraclass correlation coefficients ranged from 0.61 to 0.87.

CONCLUSIONS

All obtained validity and reliability indicators were strong and comparable with the validity and reliability coefficients of the most commonly used adaptive behaviour instruments. These results and the advantages of the DABS for clinician and researcher use are discussed.