Latent Structure of the WHOQOL-BREF: Implications for Measuring Quality of Life Among Autistic Adults

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.

Community Brief

Why is this an important issue?

Quality of life is an important outcome to the autistic community. To study quality of life, researchers need tools to accurately measure it for autistic people. Unlike measures such as a person’s height or weight, there is not one “true” way to measure quality of life. Instead, researchers use questions to learn about and measure quality of life. However, researchers need to test how well their questions learn about quality of life for autistic people. This is especially important when researchers use questions that were not made specifically for autistic people.

What is the purpose of this study?

The goal of this study is to compare different measurement models of a common quality-of-life tool—called the WHOQOL-BREF—in autistic adults. A measurement model describes how the questions in a survey are related to the idea being measured, such as quality of life. A better understanding of how the questions on the WHOQOL-BREF relate to quality of life for autistic people will help researchers do more accurate research.

What did the researchers do?

We looked at survey responses from 842 autistic adults (ages 18–83) to find the best type of measurement model for the WHOQOL-BREF. The measurement models tested whether the WHOQOL-BREF items were best related to specific quality-of-life areas (Physical, Psychological, Environmental, and Social), general quality of life, or both specific and general quality of life.

What were the results of the study?

We found that a measurement model that captures both specific quality-of-life areas and general quality of life was the best fit for the autistic adults in our study. This means that the questions on the WHOQOL-BREF capture both general and specific aspects of quality of life among autistic adults.

What do these findings add to what was already known?

These findings can help researchers use the WHOQOL-BREF to measure quality of life in autistic adults. Past research tested these types of questions in general population samples, but this study is the first to test these measurement models in autistic adults.

What are the potential weaknesses of this study?

Our findings were based on a sample of autistic adults who did not have co-occurring intellectual disability, were majority White, and many attended college. Because of this sample, we do not know how our findings may apply to more diverse samples of autistic adults.

How will these findings help autistic adults now or in the future?

Our findings provide more accurate ways that researchers can use the WHOQOL-BREF to estimate quality of life among autistic adults. We hope that having better tools to measure quality of life will help researchers improve the quality of life of autistic adults.