Psychometric Properties of Spanish Adaptation of the PDD-MRS Scale in Adults with Intellectual Developmental Disorders: The EVTEA-DI Scale

Screening for Intellectual Disabilities and/or Autism Amongst Older Children and Young Adults: a Systematic Review of Tools for Use in Africa

There are many well-developed screening tools for both intellectual disabilities and autism, but they may not be culturally appropriate for use within Africa. Our specific aims were to complete a systematic review to (1) describe and critically appraise short screening tools for the detection of intellectual disabilities and autism for older children and young adults, (2) consider the psychometric properties of these tools, and (3) judge the cultural appropriateness of these tools for use within Africa. Six screening tools for intellectual disabilities and twelve for autism were identified and appraised using the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines. We identified two screening tools which appeared appropriate for validation for use within African nations.

Screening for autism spectrum disorder in deaf adults with intellectual disability: Feasibility and accuracy of two autism screening instruments

BACKGROUND

There is a lack of autism screening instruments for deaf or hard of hearing (DHH) adults with intellectual disability.

AIMS

This study examined the diagnostic validity of the Pervasive Developmental Disorder in Mental Retardation Scale and the Diagnostic Behavioral Assessment for autism spectrum disorder - Revised in this rare population.

METHODS AND PARTICIPANTS

56 DHH adults with intellectual disability living in three specialized therapeutic communities were examined, 9 of whom met criteria for autism.

OUTCOMES AND RESULTS

With minimal adaptions regarding item interpretation, both tools showed good diagnostic and high convergent validity. Items probing for difficulties in reciprocal social interaction and restricted interests were discriminant between individuals with and without autism.

CONCLUSION

These data suggest that both autism screening tools are feasible and psychometrically sound when used with appropriate adaptations for DHH adults with intellectual disability.

Usefulness of current autism diagnostic or screening assessment tools in adults with intellectual disability (ID): systematic review of literature

Purpose

The purpose of the study is to identify and ascertain if there were any validated tools for diagnosing or screening autism spectrum disorder in adults with ID. The estimated prevalence of intellectual disability (ID) in the general population is about 10.37/1,000 population (Maulik et al., 2011). In total, 1 out of 4 individuals with ID suffers from an autism spectrum disorder (ASD) (Sappok et al., 2010). Early diagnosis and support for ASD is key to having a good quality of life. The diagnosis of ASD in people with an ID presents its own challenges and it is likely under-identification of ASD amongst adults with ID by about 20% to 30% (Emerson and Baines, 2010).

Design/methodology/approach

Studies were selected based on the following criteria: studies that reported either screening or diagnostic tools for ASD, participants had an ID i.e. a mean IQ of <70, adults i.e. participants were >18 years of age at the time of entry to the study and articles reported either sensitivity, specificity or area under the curve. Relevant studies that were published up to January 2020 were identified from EMBASE, PsychINFO, CINAHL and PubMed. In total, 75 papers were identified of which 15 papers met the criteria.

Findings

The screening or diagnostic tools currently in use is dependant on the degree of ID. A number of the tools had good psychometric properties and utility when used in people with specific degrees of ID or when used in combination with another screening or diagnostic tool. The authors could not identify a diagnostic tool that could be used across all levels of severity of ID unless used in combination. Hence, concluded that there is a need for a diagnostic tool with good psychometric properties for the assessment of ASD in adults with all degree of ID within a reasonable time period without the need for an additional tool to be used in conjunction.

Originality/value

Currently, the “gold standard” for diagnosing ASD is a lengthy and time-consuming process carried out by trained multi-disciplinary team members who assess historical, behavioural and parent/carer report to arrive at a diagnosis. There are a number of tools that have been developed to aid diagnosis. However, it is important to identify the tools that can optimise the procedures and are also time-efficient.

[Validity of the Scale of Pervasive Developmental Disorder in a Clinical Sample of Adults with Intellectual Disability]

OBJECTIVES

The study assesses the diagnostic validity of the Scale of Pervasive Developmental Disorder in Mentally Retarded Persons (PDD-MRS).

METHODS

Unblinded conduct of PDD-MRS in a clinical psychiatric sample of adults with intellectual disability (ID; N = 109) and suspect of autism.

RESULTS

For a cut-off-score of 10, sensitivity was 89 %, specificity 62 % and the Area Under the Curve (AUC) 0.83. The total score was independent of age, gender and level of ID. However the diagnostic validity was better balanced in adults with mild to moderate ID (sensitivity/specificity: 85 %/73 %) compared to those with severe to profound ID (93 %/42 %). The SEAS-M total score was correlated with various ASD screening measures (r = .3-.6), while no correlation was found for scales assessing challenging behavior.

CONCLUSION

To conclude, the PDD-MRS is a screening instrument for diagnosing autism in adults with mild to moderate ID. Knowledge of the PDD-MRS results within the consensus conference may have led to an overestimation of its diagnostic validity.