Toward a Better “Person–Environment Fit” through Items Calibration of the SIS-C

Abstract

The Supports Intensity Scale–Children’s Version (SIS-C) is the only available tool to assess extraordinary support needs for children and adolescents with intellectual disability. In past years, several works have proclaimed the need for its ongoing improvement as a measurement instrument. To contribute to this line of research, the goal of this work is to analyze the reliability of the SIS-C and its usefulness to distinguish between different levels of intensity of support needs. To address this, 814 children and adolescents with intellectual disability (M = 11.13 years; SD = 3.41) were assessed using the SIS-C Spanish version. Item response theory analyses were conducted to estimate latent scores and assess measurement quality along the support needs continuum. The SIS-C items showed good overall discrimination and information values, and none showed problems that required their removal or modification. However, all the scales composing the SIS-C showed problems in discerning high levels of intensity of support needs, especially for children and adolescents with severe/profound intellectual disability. This ceiling effect may be an obstacle for both research and practice involving the SIS-C. Implications for research and practice are discussed, and future lines of research for improving the SIS-C are provided.

Examining the Suitability of the List of Indicators Describing Age-Related Typical Support Needs

“…By stressing the interaction “person × environment”, the essential characteristic of the supports paradigm is that all people will present support needs since all people experience mismatches in certain situations and moments of their lives. The key is that the support needs of persons with IDD are extraordinary and extend beyond what most typically functioning people require to participate in the same contexts and activities [ 15 , 16 ].…”

“…The importance of the support needs construct in applying this paradigm has motivated the development of tools for its measurement. Although different approaches to measuring support needs exist, efforts are being made to develop standardized measures of the extraordinary support needs of persons with IDD based on the supports paradigm [ 15 , 16 ]. The advances in the measurement of extraordinary support needs have been evident [ 17 ], but performing a support needs assessment with psychometric instruments poses challenges that are yet to be addressed.…”

“…This challenge has direct implications for the inclusion of students with IDD: although the goal of support needs assessment is to meet the unique needs of each student, the resources and strategies available for this are limited, especially in education contexts given the cuts in education that hinder quality education for all. Therefore, knowing the areas where students with IDD have extraordinary support needs is a pressing challenge for efficient supports planning that lessens the impact of the economic cuts and brings the supports paradigm—and its implications—closer within schools [ 15 , 16 ]…”

“…Implementing the SIS-C requires the interviewer to have completed at least a four-year degree and to have received training in the foundations of the supports paradigm and in the SIS-C goal. Moreover, the interviewer must have good interview-related skills (e.g., to create a good rapport with the observers, make explicit their fears and expectations, explain to them clearly that the goal of the tool is to measure support needs and not performance or reformulate and share with the observers the information they provide to be sure that everybody has the same understanding about the support needs of the child with IDD [ 15 ]). This tool has already been implemented to expand inclusive opportunities in students with IDD within general education contexts through the development of PEPs that, consistently with the supports paradigm, support these students in key areas of their lives, thus contributing to their educational and social inclusion (e.g., [ 7 , 11 ]).…”

A Systematic Review of the Assessment of Support Needs in People with Intellectual and Developmental Disabilities

“…In addition, its application procedures have been discussed, as well as the validation of its measurement model and its generalization among groups of individuals. Recent research also identified a ceiling effect on the scale and warns about the difficulty of its use in people with greater support needs [ 31 , 32 , 33 ].…”