A comparison of the reliability and validity of SF-6D, EQ-5D and HUI3 utility measures in patients with schizophrenia and patients with depression in Singapore

Abstract

There is limited evidence of a direct comparison of the psychometric performance of generic preference-based measures in patients with mental illness in an Asian patient population. The current study aimed to compare the test–retest reliability, convergent and known-group validity and magnitude of change in scores of the EuroQol Five-Dimension, Health Utility Index Mark 3 (HUI3) and Short-Form Six-Dimension (SF-6D) measures in patients with depression and patients with schizophrenia spectrum disorder. 500 patients were recruited from a tertiary psychiatric institution in Singapore. The Schizophrenia Quality of Life Scale (SQLS), 8-item Patient Health Questionnaire, Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q), and Positive and Negative Syndrome Scale were also included. In the schizophrenia sample, the SF-6D was found to have higher test–retest validity, convergent validity with SQLS domain scores, known-group validity and magnitude of change in scores over 6-month follow up than other measures. In the depression sample, the HUI3 was found to have higher test–retest reliability, convergent validity with Q-LES-Q, known group validity and magnitude of change in scores than other measures. Results suggest that the SF-6D and HUI3 to be more suitable as a utility measure for patients with schizophrenia and depression in an Asian patient population.