Intellectual Disability (ID)

The interRAI Intellectual Disability Assessment System (ID) is a comprehensive, standardized instrument for evaluating the needs, strengths, and preferences of persons with intellectual or developmental disabilities. It is intended to be used with adults of all ages in community, residential, and institutional settings.

The instrument was developed and validated through an extensive research effort that included rigorous psychometric evaluation and pilot testing in a variety of service settings for adults with ID. The ID research team used a variety of research approaches to develop the instrument and its applications, including consultations with professionals and researchers, analysis of interRAI data from other settings, and systematic reviews of the literature. Pilot testing of the draft version of the instrument began with large-scale trials in Canada in Ontario and Nova Scotia; smaller pilots were conducted in British Columbia. Research on the psychometric properties includes face validity, convergent validity, and criterion validity (using gold standard measures of cognition, self-care skills, aggression, and depression). A small inter-rater reliability study in Ontario revealed excellent agreement between raters.

The interRAI ID is intended to inform planning for support needs, outcome measurement, quality indicators, and case-mix classification. It has been designed to be compatible with other instruments in the interRAI suite. The compatibility of assessment elements improves continuity of care across multiple settings and promotes a person-centered approach for personal support planning. The data collection form enables assessment of key domains, including social support, social participation, function, behavior, mental and physical health, and service use. Particular “trigger” items also identify persons who could benefit from further evaluation of specific issues or who are at risk for decline in well-being, function, or health.

The interRAI ID is a minimum assessment for use by professionals supporting persons with ID. It is not simply a questionnaire for analyzing the characteristics of the population, nor does it necessarily include all of the information required to construct a support plan.

Professionals should add supplemental information to the overall assessment process as judged necessary. The items in this instrument describe the performance, abilities, and capacity of the person in a variety of domains, with the majority of items serving as specific triggers for support planning.

The full interRAI ID system consists of a data collection form, a manual with item-by-item instructions, and a series of Collaborative Action Plans (CAPs ) designed to promote social and community engagement by identifying persons who may benefit from additional supports or services in specific areas. The approach to using the ID system is strength-based and fully consistent with the principles underlying support models that emphasize self-determination, choice, and empowerment. In addition, the system can produce a number of other decision-support tools common across other instrument systems, including a variety of scales and Clinical Assessment Protocols focused on health and mental health issues.

For more information, please contact the chair of the ID Development Committee Lynn Martin.