Intellectual Disability-DSM5 DR. CHARMAINE MIRANDA Clinical Director, Compass Clinic Clinical Instructor, UBC Psychiatry Clinical Associate, SFU DR. ADRIENNE ROMBOUGH Psychological Consultant, Compass Clinic
Goals of this talk: Understand DSM IV and DSM5 criteria for an intellectual disability. Understand the complexities of diagnosing ID and translate these into service eligibility.
CLBC Eligibility What are CLBC eligibility criteria for identification of a Intellectual Disability? Based currently on DSM-IV criteria for a diagnosis of Mental Retardation. Also true for: Ministry of Ed. CYMH CYSN
DSM-IV vs. DSM-5 DSM-IV: This disorder is characterized by significantly subaverage intellectual functioning (an IQ of approximately 70 or below) with onset before age 18 years and concurrent deficits or impairments in adaptive functioning. DSM-5: Intellectual disability is a disorder with onset during the developmental period that include both intellectual and adaptive functioning deficits in conceptual, social and practical domains.
Notable Changes to DSM5 1. Terminology 2. Rewording of Age of Onset Criteria 3. Axis 1 diagnosis 4. Reduced Prominence of IQ score 5. Encouraged to add Causal Specifiers 6. Assignment of Severity Specifiers 7. Rewording of Adaptive Behaviour Criteria
DSM5: Intellectual Disability 1. Terminology: Intellectual Disability versus Mental Retardation 2. Rewording of age of onset: Onset in the developmental period versus before age 18 3. Axis changes: Axis II is removed. ID is now an Axis I diagnosis.
Defining ID Reduced Prominence of IQ: (DSM-4) Criterion A: Significantly subaverage intellectual functioning: an IQ of approximately 70 or below on an individually administered IQ test. (DSM-5) Criterion A: Deficits in intellectual functions, such as reasoning, problem solving, planning, abstract thinking, judgement, academic learning, and learning from experience, confirmed by both clinical assessment and individualist, standardized intelligence testing. IQ tests scores are approximations of conceptual functioning but may be insufficient to assess real-life situations and mastery of practical tasks. Understanding that an IQ test is only a number. IQ still important but less prominent (approximately 70-75 or under)
DSM5: Intellectual Disability Causal factors e.g., ID associated with genetic diagnosis of Down Syndrome Severity based on adaptive functioning
Rewording of Adaptive Behaviour Criteria (DSM-IV) Criterion B: Concurrent deficits or impairments in present adaptive functioning (i.e. the person s effectiveness in meeting the standards expected for his or her age by his or her cultural group) in a least 2 of the following areas: communication, self-care, home living, social/interpersonal skills, use of community resources, self-direction, functional academic skills, work, leisure, health and safety. (DSM5) Criterion B: Deficits in adaptive functioning that result in a failure to meet developmental and socio-cultural standards for personal independence and social responsibility. Without ongoing support, the adapative deficits limit functioning in 1 or more activities of daily life such as communication, school participation and independent living, across multiple environments, such as home, school, work and community. Limited functioning in at least 1 area : Conceptual, Social, or Practical.
What is IQ and how is it measured? IQ = Intelligence Quotient as measured on standardized, interactive tests with trained examiner. Historical IQ tests measured a child s mental age and compared it with their chronological age. Modern IQ tests compare an individual s score with a standardized sample of people with the same-aged to derive a percentile score.
IQ is not a Unitary Construct On the Wechsler Scale of Intelligence for Children (WISC) and the Wechsler Adult Intelligence Scale (WAIS), the Full Scale IQ is a summary score based on four Index scores (part scores): Verbal Comprehension (verbal concept formation, verbal reasoning, and knowledge, acquired from one s environment) Perceptual Reasoning (perceptual and fluid reasoning, spatial processing and visual-motor integration) Working Memory (ability to work with information stored temporarily in memory) Processing Speed (ability to quickly and correctly scan, sequence, or discriminate simple visual information)
What is the General Ability Index (GAI)? GAI: A summary score comprised of the Verbal Comprehension Index and Perceptual Reasoning Index scores Verbal Comprehension (VCI) Perceptual Reasoning (PRI) Working Memory (WMI) Processing Speed (PSI) Full Scale IQ (FSIQ) General Ability Index (GAI) Scaled Score 73 87 77 94 78 76 Scaled Score 122 116 97 80 108 123
Other considerations How to apply the DSM IV and DSM 5. Does the person meet diagnostic criteria? history/interviews/file review, IQ and adaptive functioning test scores What are the differential diagnoses? How will a diagnosis affect access to supports/services? What are the legal precedents?
Differential Diagnoses for ID Global Developmental Delay (GDD): identifies a child aged 5 or under who is failing to meet expected developmental milestones in several areas of intellectual functioning but is unable to undergo systematic intelligence testing. Retesting is required. Neurocognitive Disorders: identify an individual who has experienced a significant decline in cognitive ability and adaptive functioning/independence in everyday activities. Due to an illness, trauma, medical diagnosis. (e.g. Alzheimer's, vascular disease, head injury)
Legal Influence on Society s Idea of ID 2002: Atkins: court decided that a person with MR could not be executed (thereafter called the Atkins death penalty exemption) 2005: Hawthorne: IQ within low average range, but ADHD, deemed eligible for Atkins exemption. 2007: Vidal case: Verbal IQ in the 50 s, but Performance IQ average to high average. FASD dx. Deemed to be eligible for Atkins exemption 2008: Hearn case, V/P split, and FASD. Also deemed eligible for Atkins.
The role of clinical judgment DSM-5 Criterion A: Deficits in intellectual functions, such as reasoning, problem solving, planning, abstract thinking, judgement, academic learning, and learning from experience, confirmed by both clinical assessment and individualist, standardized intelligence testing. Blurring of diagnostic boundaries? Greater room for clinical judgment.
Tough Case Examples LET S PRACTICE!
Case Study 1: G - aged 16 years G is diagnosed with autism, ADHD, Oppositional Defiant Disorder, Anxiety Disorder, and Soto s Syndrome G would light fires in his room and smear feces on the walls. He used knives to cut and destroy things. He damaged flooring and walls in his family home. Due to his extensive care needs and unpredictable behaviour, G required 24/7 supervision. During his stay at an inpatient psychiatric unit, G often required 2:1 support. He was as stable as he was likely ever to be when tested.
G s WISC-IV Index Scores WISC IV Index Standard Score Percentile Rank 95% Confidence Interval Qualitative Description Verbal Comprehension (VCI) 91 27 84 99 Average Perceptual Reasoning (PRI) 85 16 78 95 Low Average Working Memory (WMI) 71 3 66 82 Borderline Processing Speed (PSI) 50 <0.1 47 63 Extremely Low Full Scale IQ (FSIQ) 72 3 67 79 Borderline General Ability Index (GAI) 86 18 80 93 Low Average
G s WISC-IV Subtest Scores
G s Adaptive Functioning & Challenging Behaviour Scores G s everyday adaptive living skills and challenging behaviours were assessed using the SIB-R (a common care-giver report measure). The Broad Independence score is a summary score for overall adaptive living skills. Composite/ Subdomain Standard Score Percentile Qualitative Description Age Equivalent Broad Independence 40 0.1 Well Below Average 6:4 Generalized Maladaptive Index 50 --- Very Serious --- Internalized 32 --- Serious --- Asocial 42 --- Very Serious --- Externalized 40 --- Serious --- The General Maladaptive Index score is a score summarizing challenging behaviours and need for behavioural support/supervision. G s social and emotional maturity was reflective of a much younger child. His need for direct supervision was high. Functionally, G s abilities/skills corresponded to his Full Scale IQ score.
G s Academic Scores Subtests Standard/ Scaled Score Percentile Qualitative Description Grade Equivalent Age Equivalent Word Reading 102 55 Average 12.4 17:0-19:11 Reading Comprehension 97 42 Average 8.7 13:0 Math Problem Solving 74 4 Below Average 4.5 9:4
Would G meet DSM-IV criteria for MR? Would G meet DSM5 criteria for ID?
Summary of G s Assessment Results When there s variability in Index scores, consider: Functional Impairment Consistency with Full Scale IQ Confounding variables Age and access to services One single Index score is not a good representation of strengths and weaknesses. Use Full Scale IQ unless there is a valid reason not to. Some skills/scores might be considered splinter skills and not reflective of overall dysfunction E.g., Children with Williams Syndrome show strengths in language and memory
Summary of G s Assessment Results In everyday life, G is functioning below the level of a 6 year-old. G s reactivity and impulsivity are even lower than this level. His functioning is impaired because of very significant impairment in executive functioning, well below average social-emotional maturity, and severe reactivity and impulsivity. G acts without thinking, is reactive, engages in antisocial behaviours and encourages others to do the same. G was diagnosed with Mental Retardation (DSM-IV)
Case Study 2: Stephie - aged 22 years Head injury at age 14. Diagnosed with an acute psychotic episode at age 16. Extremely disordered behaviour: History of SIB: She was reported to carry around a knife and used it to cut herself. Paranoid, obsessive and repetitive thoughts and behaviours, many centering around her fear of contamination. Impulsive stealing Disordered eating, including bingeing and purging, hoarding food and refusing to eat. Ongoing issues with incontinence and soiling. history of smearing feces on the walls. Does not plan her clothing for the weather or social setting. At times, she has exposed herself inappropriately. During her stay at the psychiatric inpatient unit, she would wear men s underwear on her head. Demonstrates baby-like behaviours, such as using a soother, eating baby food, wearing baby clothes and wearing diapers.
History of Stephie s IQ Scores Year Full Scale IQ Score Age 2006 80 16 2009 <70* 19 2012 61 22 *Exact Full Scale IQ score not reported due to discrepancies between Index scores. Stephie was found to meet criteria for a Mild Intellectual Retardation in 2009
Stephie s Index Scores (February 2012) WAIS IV Index Standard Score Percentile Rank 95% Confidence Interval Qualitative Description Verbal Comprehension (VCI) 54 0.1 50 63 Extremely Low Perceptual Reasoning (PRI) 78 7 73 86 Borderline Working Memory (WMI) 58 0.1 54 69 Extremely Low Processing Speed (PSI) 72 3 66 83 Borderline Full Scale IQ (FSIQ) 61 0.5 56 69 Extremely Low
Stephie s Adaptive Functioning Stephie s adaptive functioning was assessed using the SIB-R Composite/ Subdomain Standard Score Percentile Qualitative Description Age Equivalent Broad Independence 5 <0.1 Well Below Average 5:1 Motor Skills 10 <0.1 Well Below Average 3:10 Social/Communication 36 0.1 Well Below Average 6:3 Personal Living 25 0.1 Well Below Average 4:8 Community Living 6 0.1 Well Below Average 5:9
Does Stephie meet criteria for diagnosis under DSM-IV? Under DSM5? Does she meet CLBC eligibility criteria?
Summary of Stephie s Assessment Results Based on the results of the assessment, Stephie was felt to present with a profile in keeping with that of a Mild Mental Retardation (DSM-IV). Results of cognitive testing were generally consistent with those documented in her most recent previous assessment (2009). Does onset of psychosis at age 16 change the ID diagnosis? If Stephie s psychosis started at age 25 and brought down her IQ, would she still meet DSM5 criteria?
Case Study 3: Nancy age 6 Presenting Issues Confirmed pre-natal alcohol and poly-substance exposure. One of 7 children from bio-mother. Family hx: Bio-mom described as generally slow, 3 siblings have ASD. History of placements in foster care (poverty/neglect, exposure to domestic violence) Moderate speech and language delays Behavioural concerns (tantrums, self-harm, difficulty with changes in routine, hyperactivity)
Behavioral Observations from Testing Attention comes in and out of focus Tends to be impulsive Likes some tasks but dislikes others. Not very engaged when she doesn t like a task. Overall: Sweet, friendly, socially-responsive. Enjoys pretend play.
Nancy s Index Scores WPPSI- IV Index Standard Score Percentile Rank 95% Confidence Interval Qualitative Description Verbal Comprehension (VCI) 62 1 57-72 Extremely Low Visual Spatial (VSI) 73 4 67-85 Borderline Fluid Reasoning (FRI) 80 9 74-89 Low Average Working Memory (WMI) 76 5 70-86 Borderline Processing Speed (PSI) 77 6 71-90 Borderline Full Scale IQ (FSIQ) 60 0.4 56-68 Extremely Low
Nancy s Adaptive Functioning G s everyday adaptive living skills were assessed using the ABAS-II (a common care-giver report measure). Composite Standard Score Percentile Qualitative Description General Adaptive Composite 65 1 Well Below Average Conceptual 69 2 Well Below Average Social 65 1 Well Below Average Practical 70 2 Well Below Average
Nancy s WPPSI-IV scores
Does Nancy meet criteria for diagnosis under DSM-IV? Under DSM5? Does she meet CYSN/Ministry of Ed eligibility criteria?
Summary of Nancy s Assessment Results Based on the results of the assessment, Nancy was NOT felt to present with a profile in keeping with MR (DSM-IV) or ID (DSM-5). Her profile was found to be more consistent with FASD. Do you agree/disagree?
Questions for Discussion If someone has normal development until the age of 7 and has a head injury that arrests their development, would they be considered eligible for a diagnosis of an Intellectual Disability? If someone has a head injury at age 30 would they be eligible for a diagnosis of an Intellectual Disability? Should they be eligible for CLBC support? If drug use has resulted in cognitive results scoring below 70, does this individual meet criteria for an intellectual disability? Would age of the drug use change the decision for diagnosis?
Take Home Message It takes a Clinician not a Technician to determine ID in these difficult cases. We have to consider multiple factors, including age, support requirements, variability in functioning, and course of presentation. In any report where the cognitive presentation is unusual, the summary should clearly outline the clinician s thought process and why ID was diagnosed or not.
References & Recommended Reading American Psychiatric Association. (2013). DSM5 Intellectual Disability Fact Sheet. Bergeron, R., & Floyd, R.G. Broad Cognitive Abilities of Children with Mental Retardation: An Analysis of Group and Individual Profiles. American Journal on Mental Retardation 111(6): 417-432. November 2006. Carulla, LS., et al. Intellectual Developmental Disorders: Towards a New Name, Definition and Framework for Mental Retardation/Intellectual Disability in ICD-11. Word Psychiatry 3 (10): 175-180. October 2011. Cheung, N. Defining Intellectual Disability and Establishing a Standard of Proof: Suggestions for a National Model Standard. Health Matrix 23 (1). 2013.