Abstract
BACKGROUND: To accurately measure quality of life among autistic adults, researchers need surveys that are psychometrically validated for autistic populations. Researchers have demonstrated that the short version of the World Health Organization Quality of Life instrument (WHOQOL-BREF) has strong psychometric properties in the general population. Although there has been some research exploring basic psychometric properties (reliability, convergent validity, etc.) of the WHOQOL-BREF in autistic populations, the underlying latent structure of the measure has not been tested in autistic adults. Our goal in the current study was to compare different confirmatory factor analysis (CFA) models to test which one best captured the underlying latent structure of the WHOQOL-BREF data in a sample of autistic adults. METHODS: A total of 842 autistic adults between the ages of 18 and 83 years completed the WHOQOL-BREF. Based on participant responses, we compared four a priori CFA models-correlated four-factor, unidimensional, higher-order, and bifactor models-to demonstrate which model structure best captures the underlying latent structure of the measure in this population. RESULTS: Similar to past research, the WHOQOL-BREF showed strong internal reliability in our sample of autistic adults. The bifactor model demonstrated the best fit to the data-demonstrating that the WHOQOL-BREF is best conceptualized as having both domain-specific quality-of-life factors (i.e., the Physical, Psychological, Environmental, and Social domains of the WHOQOL-BREF) and a general quality-of-life factor. CONCLUSION: Our results provide researchers with psychometric validation of the underlying latent structure of the WHOQOL-BREF in autistic populations. Items on the WHOQOL-BREF capture both domain-specific and general quality of life among autistic adults. Researchers can use the bifactor model to accurately capture multiple dimensions of quality of life in autistic adults, advancing the ways that the WHOQOL-BREF can be used as a measure of quality of life among autistic people.