Framework for assessing individuals with rare genetic disorders associated with profound intellectual and multiple disabilities (PIMD): the example of Phelan McDermid Syndrome

Clin Neuropsychol. Aug-Oct 2018;32(7):1226-1255. doi: 10.1080/13854046.2017.1413211. Epub 2017 Dec 21.


Background: Specialized strategies are needed to understand the complex neuropsychological impairments reported in individuals with profound intellectual and multiple disabilities (PIMD) associated with rare genetic disorders.

Methods: This narrative review focuses on assessment of individuals with Phelan-McDermid Syndrome (PMS) as a condition commonly associated with PIMD. Published case series and prospective studies were reviewed to evaluate approaches to cognitive, language, motor/sensory, and behavioral domains. This review is framed using general principles for neuropsychological evaluation in PIMD.

Results: Neuropsychological assessment domains and tools varied across published reports. Adaptive behavior measures, out-of-range developmental assessments, and social-communication measures were commonly used. Available findings were used to shape a recommended framework with potential to improve measurement of clinical outcomes and advance scientific discovery.

Conclusions: The recommended framework outlines an inter-disciplinary and multimodal neuropsychological assessment process relying on modified standardized assessments, functional assessments, and caregiver/informant reports when evaluating individuals with PIMD. Arrested development and skill variability/regression are also discussed as additional, important considerations in neuropsychological evaluation of individuals with PIMD and rare genetic disorders.

Trial registration: NCT01778504.

Keywords: Intellectual disability; Phelan-McDermid Syndrome; cognition; neuropsychological assessment.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural
  • Review

MeSH terms

  • Caregivers / psychology
  • Chromosome Deletion
  • Chromosome Disorders / diagnosis*
  • Chromosome Disorders / genetics
  • Chromosome Disorders / psychology*
  • Chromosomes, Human, Pair 22 / genetics
  • Communication
  • Female
  • Humans
  • Intellectual Disability / diagnosis*
  • Intellectual Disability / genetics
  • Intellectual Disability / psychology*
  • Male
  • Neuropsychological Tests*
  • Prospective Studies

Supplementary concepts

  • Telomeric 22q13 Monosomy Syndrome

Associated data