The adaptation of self-report measures to the needs of people with intellectual disabilities: a systematic review

Background
Persons with intellectual disabilities (ID) may have difficulties providing reliable and valid accounts of their personal experiences through self-report measures. The aim of the current study was to systematically review the peer-reviewed research literature on the adaptations needed to develop ‘ID-inclusive’ self-report measures.

Method
A search of PsycINFO, PubMed, Web of Science and Google Scholar identified 49 studies that met inclusion criteria. A GRADE-CERQual assessment was performed to determine the level of confidence in the review findings.

Results
161 recommendations for the development of ‘ID-inclusive’ self-report measures were extracted from 49 included studies. Recommendations were presented in a GRADE-CERQual Summary of Findings table, according to a 5-stage model of instrument development.

Conclusions
This review offers much-needed practical guidance for clinicians and researchers on how to develop ‘ID-inclusive’ self-report measures. Recommendations for future research about self-report instrument development for use with people with ID are presented.