Rasch validation of the Warwick-Edinburgh Mental Well-Being Scale (WEMWBS) in community-dwelling adults

Abstract

Background: With the ongoing global COVID-19 pandemic and the recent political divide in the United States (US), there is an urgent need to address the soaring mental well-being problems and promote positive well-being. The Warwick-Edinburgh Mental Well-Being Scale (WEMWBS) measures the positive aspects of mental health. Previous studies confirmed its construct validity, reliability, and unidimensionality with confirmatory factor analysis. Six studies have performed a Rasch analysis on the WEMWBS, and only one evaluated young adults in the US. The goal of our study is to use Rasch analysis to validate the WEMBS in a wider age group of community-dwelling adults in the US. Methods: We used the Rasch unidimensional measurement model 2030 software to evaluate item and person fit, targeting, person separation reliability (PSR), and differential item functioning (DIF) for sample sizes of at least 200 persons in each subgroup. Results: After deleting two items, the WEMBS analyzed in our 553 community-dwelling adults (average age 51.22 ± 17.18 years; 358 women) showed an excellent PSR = 0.91 as well as person and item fit, but the items are too easy for this population (person mean location = 2.17 ± 2.00). There was no DIF for sex, mental health, or practicing breathing exercises. Conclusions: The WEMWBS had good item and person fit but the targeting is off when used in community-dwelling adults in the US. Adding more difficult items might improve the targeting and capture a broader range of positive mental well-being.